Hey, thanks for considering, any method, PayPal, TH-cam, patreon etc will all take a small portion sadly, but after all we get to use their platform for free which is pretty awesome :)
I agree!. I have "done it ALL" i thought, haha. I also refuse to be "Beaten by a Two stroke engine" and anything mechanical really. - " Can We FIX it? YES We CAN!(Bob the Builder) 🙂😇😄
I'm VERY impressed by your knowledge of small engines. You did a wonderful job of diagnosing the problem. Thank you to taking the time and trouble to record, edit, and post this video. Much appreciated.
It’s a pleasure Kevin! Comments like yours really mean a lot to me as you are aware of the extent of the effort videos take to make. That’s awesome and thank you again!! It gives me the motivation to continue :)
This is great info that so many young techs never learn. Having said that, from a repair shop point of view its quicker and cheaper for the customer to just replace any carb that won't prime.
Spot on Scott, this isn’t something the average shop would be able to justify. It’s something I’d recommend to a home owner wanting to get their machines working again or even someone running their small engine repair business that is offering an alternative to an expensive oem carb when costs need to be kept down :) I calculated that what I’d charge for my time to do this would be 3x cheaper than the customer buying an oem carb. That said my overheads are minimal compared to a shop of course!
For now it's economical to replace the card but it won't be as new anti-petrol regulations set in making all of this impossible to maintain without critical knowledge.
I have been replacing metering diaphragms, purge bulbs and fuel lines in these carburetors for years and never knew how they really worked and that they may have a fuel pump. Thanks for the detailed information.
Thank you John, I do my best to save everything be it a beautiful vintage engine through to a fuel filter. As silly as it sounds, everything is stupidly expensive out here and if you order it online it’s 2 - 8 week wait!
Fantastic Job. The amount of time, energy and information you placed in this video is a gift to all.. Not only did I learn a great deal, but to think on the amount of items that may be repaired / rehabbed, then placed back into service rather than being thrown away, was very inspiring to me.
Great stuff! This video will teach you everything you’ll ever need to know about these cube carbs :) I hope you enjoy it! th-cam.com/video/_4K6dBQTeek/w-d-xo.html
Haha thanks Kenny, I still have a lot more to learn though! Have fun with it :) if I find the o-rings I’ll send them your way. I believe they do come in a few sizes, but we’ll see!
god that was quick!! thank you, I think the tank filter is a good starting point and work back it is 25 years old after all! did put a kit in it 2 years ago and was working well at that time! cheers, Alan.@@VintageEngineRepairs
You are the best. WOW. Learned more in 10 minutes, than I knew previously and I've been doing this for awhile. You are "THE PROFESSOR OF CARBURATORATION "
I have spent hours trying to solve this issue. I ended up replacing the carb but that is an admission of defeat. I will try again with my new found knowledge and win this time. Thanks for teaching me.
Great video. I know quite a lot about carburetors, but you are definitely on another level. Thanks for sharing, and I'm going to have to check the rest of your videos. Cheers.
Liked, you are amazing. On my trimmer. I prime the bulb. Crank the engine and it runs perfect for maybe 3 mins then stops You have to reprime and crank again. Same thing over and over again. It's like the bulb is losing its prime. Any idea what might be happening? Haven't seen my problem discussed on the web. Thanks in advance.
Hey! Thanks for the kind words. I’d personally take the carburettor apart, put a new kit in it and maybe give it a tune. Check fuel lines and filter too 👍👍
Yes I did remove the 2 spots where there was pink wax. Came off easily with carb cleaner and flathead. I thought it was built up gunk but maybe was it was placed there by the factory. Thank you for the great video
Yeah carb cleaner strips it. It’s a sealer to stop the welch plugs leaking. Now days they don’t use it due to ethanol, you should be just fine without it!
I'm very impressed by your knowledge of small engines. I've worked on them all my life and never knew anything about using a hand pump to pressure test the fuel system. Subscribed!
I did not know that these carbs have an accelerator pump. After watching your video I pulled the carb, attached a temporary line to the inlet and immersed into fuel mix. The primer bulb would not lift any fuel. I then opened the throttle shaft and applied a few drops of 30w oil past the flat to cover the accelerator pump piston, closed the throttle and tried to prime again. The bulb immediately lifted fuel and filled. This was a quick way to confirm that the O ring was at fault. Upon disassembling, the O ring was brittle and broke in 2 pieces when removing. I replaced the O ring with a generic nitrile 1mm x 3mm id. All is working as it should now. Thank you for your clear and concise explanation.
Ive been scratching my head as to problem cause on my fs40 carb... watched this ... straight out to workshop and boom fs40 priming and running sweet!! You absolute star just saved my a fortune.
The breakdowns of what is happening inside the carb, the drawings to understand it better, the first grade way of explaining things. This guy knows what he's talking about. Been struggling with my husqy for the weekend and this is it, the problem and the solution. You've saved me $20 on buying a new carb. You are awesome and I appreciate the very well informed explanation. Definitely subscribing after this one. Cheers mate!
That’s the only thing that gets fuel to the carburetor, yes :) the impulse, that the piston rings create, is what pumps fuel. The Venturi effect doesn’t draw the fuel into the carb as much as it does draw it out of the metering chamber haha.
Dude! This was great. Subbed on the first vid. I love that you know the form, function, proper description and definition of even the slightest nuance of a carburator...and you can't remember to say "SUBSCRIBE"! Bloody marvelous, mate.
Haha thank you! Much appreciated :) I have always felt that people will subscribe if they like your content. No amount of asking will change that, it just gets annoying.
Excellent!I've just spent 2 hours today with this problem. Luckily i have orings.if it doesn't work,plan B,nail varnish. I'll come tomorrow with an update. Thanks again!
@VintageEngineRepairs I'm extremely impressed by your expert knowledge on these units. In particular your ability to perform a bespoke repair by using your understanding of the pump and sealing dynamics is a skill I'd really love to develop I've been repairing power tools and small engines for a couple of years now but still don't fully understand carburettor operation. Are there any books or resources you used to get your knowledge up to this level?
Thank you for your kind words :) I have videos on how they work and more coming out very shortly. Start with this one :) th-cam.com/video/_4K6dBQTeek/w-d-xo.html
Great video! I might add that if you are in the US, you will likely be dealing with ethanol in the gasoline, the alcohol in which will destroy nail polish. So use a product like Seal All that is resistant to the alcohol.
@@VintageEngineRepairs Recently found your channel, some great info in all those video's. This a particularly helpful video explaining the possibility of an air leak at the plunger o-ring - not necessarily just the idle and main jet non-return valves allowing the purge bulb to suck air, nice work! Since the introduction of E10 fuel here in GB, my use of nail varnish when resealing welch plugs has had to stop. Nail varnish seemed to be ok with E5 fuel. Have you noticed that the original welch plug sealant used by Zama and Walbro has been falling out and blocking jets/valves for some years - I wondered if it was being affected by the E5 fuel. I've just done the same seal up job with nail varnish on an FS85. With the small surface area of varnish actually in contact with fuel I'm hoping the job should last for a reasonable time. We'll see...
Thanks for this ❤ I have spent countless hours on Stihl carbs trying to fix a non priming problem without realising that this accelerator pump even exists. i have seen the small screen in the repair kits and wondered what it was for but they never included an o ring 🙄 have bought a pack of 1x3mm o rings as another viewer described. No amount of carb cleaning would have solved this issue. Thanks again 🙏
Thanks so much mate. sure enough was the same issue as this video. You were walking past my place and stopped in and gave me some advice. I would love to come round and get a masterclass in 2 strokes if you were ever interested.
Thank you. I have a Stihl FS45 line trimmer that's just out of warranty. The bulb wouldn't fill and would remain completely dry, just like the one you demonstrated. The carb is ostensibly identical to that in your video. Pulling it apart, cleaning and reassembling it, didn't initially solve the problem. Eventually I took the cover off the fuel-pump side, as you demonstrated at 2:40. I couldn't see anything wrong with the rubber gasket and its two flapper valves (I presume). Regardless, I removed the thin rubber gasket. It was well adhered to the metal surface and I feared I was going to tear it. Anyway, no damage seemed to be done in its removal. As I could see nothing wrong, I reassembled that section and the rest. After reassembly of the carb I put the intake pipe on my lower lip (dry) and pressed the bulb a few times. I could now feel it sucking. My fingertip wasn't sensitive enough to detect it. I put the carb back on the line trimmer and pressed the bulb a few time. It now filled with fuel. I'm not sure what fixed it and how. Unfortunately, the trimmer still won't start. There was something I noticed on the metering side. The diaphragm looked lumpy, as though it had tried to expand, sort of like when paper dries after being wet. The other thing is that the bulb, once filled, resists further pumping. I don't know if that is normal. Thank you for your video; I have liked and saved it.
Hey there, I just happen to catch this video as I was scrolling . I really like how you explain what you're doing and how it works, that makes more sense than what I've heard. The drawing helps, and the close ups with magnified. That helps when it's so small. Thank you
Yes you did great, maybe speak a tad louder or have a mic closer to your mouth if possible. But yeah, I do a little small engine repair, I use TH-cam as a guide. For refreshing my skills. Most videos don't go into depth of taking it apart and explaining it more thuroughly as you have. So I'll definetly be watching more of your vidios. I took small engine course in HS. I was the only female. So we had to lock my engines in shop techs office to protect it from the guys vandaling it. But it's been 30+ years. So these videos are great refreshing for my memory lapse of time. Thank you! 😎👍
@@suzanemartin8242 so sorry to hear of how it use to be. I have heard many stories of the nonsense that use to go on back then. Thankfully times have changed and we see more woman in the repair industry and flourishing. I’m so pleased you didn’t give up. I’m always here to help when I can :)
Strange as it seems, it hasn't changed that much. The guys make it super hard to keep jobs. I aced the small engines even thou. But got crazy and went into auto body r/r. Again only female. My husband scared the poo outta those guys, after I reported my projects being damaged by vandal. That was college. I finished in the top 3 in college. But I was lucky if I was hired. Let alone they savataged my work. So in the NW, it's still very hard for a female to even get started in mechanical world. But I got burned out on fighting for employment. Had to support my kids. Couldn't keep going on. So I just enjoy it for my own good. Nice to know skills.
What would cause the bulb to be hard and not fill with fuel? After a few pushes the bulb will stay down but still no fuel. And its an Echo 2620 if that helps. About 6 months old. Im assuming the check valves under the primer bulb?
Yep! Can be the valve not letting fuel in that is blocked. Could be a stuck metering lever, very clogged screen, blocked fuel line. Something is blocked in the circuit :)
Really I have had that problem and was able to buy a o ring kit from Harbor freight and in that kit is several o rings that can be used. Just a thought if you really want to fix it for a little bit of money you can. But like the one guy said you can order a new carburetor for cheap to and the one’s I buy come with hoses and filter. Easy peasy.
Great question! I’m only guessing here as I can’t be certain, but with the limiters in place and the use of an accelerator pump they can have it set leaner at idle and still get good off idle acceleration. However I remove the limiters so can get past it. Notice at the end of the video I say it’s a bit lean and richen it up? That could be the requirement. Though honestly I can’t tell you, I’m simply guessing!
much appreciated! Rarely do people explain how it actually functions. I have a variation of this carb the keeps leaking fuel when i pump the bulb. Trying to understand why.
Hi thanks for the video, i like to try and fix things too theres no fun to be had with cheap chinese copy carbs unless you like retuning your machine every time you use it! I would rather a serviced genuine carb. Can we just uae a normal rubber oring out of a cheap oring kit, or does it need to be viton or similar? Another thought might some dot3 brake fluid ir silicone spray rejuvenate/swell the oring enough to get it back to size
@@VintageEngineRepairs thanks for reply :) I have seen your video on diaphragms, will try a few different things I'm about to tackle an fs45 this arvo! Maybe a very thin slice of 3.5mm od fuel line would do the trick?
Works on some things, thinking would be an idea while servicing carbs to just sit a dob of silicon spray on the check valve for the rubber to soak up, just for good measure! prevent maintenance ..or just Asking for trouble? :) what do you think
It depends firstly on the material, many kits are just rubber orings and will fail right away, the other is it’s a very unique size. Therefore it’s not in any kit i or anyone else I know, has found!
Speaking of holes on the body of the carb, do you know what the hole is on a br600 carb right under the high/low screws on the carb body. It sprays out fuel while running. Don't know if it's leaking while not running.
I have a blower that starts and idles fine but cuts out after a couple of seconds of any significant throttle. The primer sucks about 50% air when releasing the purge bulb. I chased it through to the main nozzle not sealing. I flooded the venturi with WD40 and it finally held vacuum when purging with a blocked fuel inlet. Thought I had fixed the nozzle valve but it runs just the same as before. A main nozzle locked open should give me the opposite symptoms of rough idle and good WOT? No accelerator pump on mine just a build-in choke. I think maybe high jet is partially obstructed? Need to get one of the pacmans to get in there
Try opening both the L and H screws 1/4 of a turn and see if it improves it. An open main nozzle will give you lean symptoms at idle but be fine at full throttle.
Brilliantly explained video . I am amazed at your knowledge and explanations . I have several Stihl tools and to be honest I never did understand the intricacies of how a carb works . I usually replace diaphragm and gaskets , fail , and then replace carb . I have a Stihl sh86 blower that only fires once but fails to start . so I have 100 psi of compression , a good spark , replaced all carb parts and after a half day episode it still does the same . Fires once and no more . I have a new Stihl blower but would love to get this old one going just because I believe it is something very minor . Just a great video , I would love to know where you obtained all this technical info , really impressed .
Thanks for the kind words, a lot of what I have learnt has been from stihl manuals that are for their technicians, also through research online, good mentors around me who help and and frustratingly obsessive personality that doesn’t let me give up until I understand something. Re your 100 psi. This is actually too low for a 2 stroke ope engine to run. They say 120 is about the lowest and even then it won’t run well (if at all). The caveat here is if your compression tester is not designed for small engines, that could be why it’s low, even if the engine is good. Too much to explain in a message, but here is a video on the topic - th-cam.com/video/M6eXO6n8hhg/w-d-xo.htmlsi=7zrVpHYwLpbOuqhQ Note on some occasions 2 stroke engines are low compression (70 psi and they’ll run) but not in outdoor power equipment. They need about 150psi.
Back again , thank you for your reply . I will study your recommended video and I think it will be prudent to check compression on the new blower . Both are Stihl sh86 models, the problem one I have for maybe 12 years . Just for your info , the new one gave a slight problem in that the outer stop lever stuck down in the off position due to the very cold weather and the tight fitting of lever . I removed the upper hand , greased and freed out a bit and that solved the problem . The lever is designed to spring up into the start position automatically . Initially I did nor realise this and on account of hearing that the petrol quality has changed I believed that was the problem . Anyway thank you again .@@VintageEngineRepairs
Thanks Tom, really helpful video. The nitrile O rings are a standard size so you can just buy a pack of 20 for next to nothing off Ebay rather than disabling the accelerator pump. Lovely clear explanation though and I like your shade of nail varnish.
Thank you! Yes now days I have all sizes to hand, it’s best to keep things original and replace the o-ring wherever possible. Glad you have the o-rings too! Thanks for watching and commenting :)
Hi Tom, i have just done a Stihl FS 38 same problem no priming but i have just put a Chinese carb on, there is few few videos on them type of strimmers not priming, but you have done well finding out what the problem is, the small seal is that about the same size that @henrymurawskibigdogrepair was looking for and got
I think my problem is a worn o-ring on the accelerator pump piston. I've ordered some o rings, but in the mean time, I was wondering if there was a way to 'mod' the piston to reduce wear OR remove the need for the oring? The bore is 4.00mm but the piston is only 3.75mm. That alot of play for such a small size. I wonder if a better fitting pistion ( without o ring ) would work better? Another thought was to fit a second o ring at the other end of the piston to keep it square int eh bore, better. thoughts? Steve
Yes in joyed watching the video,great job showing and telling.if I tried that I wood miss it up I think, but thanks again for showing telling your good at it keep up the good work see ya next time see ya bye.
You didn’t explain that the reason the engine was bogging was because the accelerator pump was now disabled, and the carb had to be adjusted to richen up the low speed side to compensate for that lack of additional fuel upon opening the throttle.
Well, he had to adjust it again anyways because he had removed the adjustment screw so that he could thread in the throttle shaft and tighten up on the spring tension. Sometimes we need to try and figure out the finer details ourselves and be grateful to others for sharing the major details of their work experience in doing some stuff, whether it be mechanical or otherwise. Anyways, I worked on a Stihl weed eater and it would have cost $50 to ship a replacement carb over in a week to two.
I was wondering what channels there were under that round Welch plug on my Stihl FS38. No matter which hole I squirt acetone through, I can't get it to come out of the Main nozzle.
If you can’t get fuel through the main nozzle, it’s likely sealed shut. Connect a tube to the H circuit through one of the drillings and close the others with your finger and blow and suck. Listen for a clicking sound. If it doesn’t click or you can’t blow, the valve is shut. It may free up in the ultrasonic cleaner
Thank your for the video! My BRAND NEW replacement carb has got to be sucking air - as evident by some bubbles in the fuel line. This video gave me a few ideas to chase after. Thanks a Bunch!
Hi great vid thanks. Couldn’t you replace the O ring with one out of a box of assorted O rings ? I get why the Stihl kit was cost prohibitive as so in the UK I Worked out their price strategy they simply charge £10 per part hence making a replacement carb more cost effective. Does the nail polish fix last for a long time ? Or does the fuel rot it ? Many thanks Nick
Hey loads of great questions! Over time nail varnish will dissolve in ethanol fuel. If you’re running non ethanol fuel it won’t. You can absolutely just replace the o/ring if you have one, but it has to be fuel resistant, so nitrile or viton. Just for your reference, they’re 3x1 :)
I had this exact problem today bought new fuel line and fiĺter installed them and then the purge bulb slit went and got another one and couldnt understand why it wasnt getting fuel up into the bulb thanks for making this video
Do you have a video on primer bulbs? Cause I have that issue with a Poulan and it says primer above it. It's basically doing the same thing. Not wanting to draw fuel in it
Thank you so much for all your input on the 2 cycles. I've been working on him a long time. And I just learned some new things from you. Please keep up the good work, and thank you again. Yes, i'm across the pond, hello
Would you be able to answer a question for me. I recently brought a petrol strimmer from Sgs and never used it. I return the strimmer to them unused condition when they looked at it they said as there was fuel in the priming buld i had added fuel and attempted to start it, which i did not. My question is would there still be fuel in the buld from them testing the strimmer as surely they would have tested it first. I would really appreciate your thoughts. Many thanks.
Will the vaccum system of the purge bulb work and get it full when you press it and realeased if the carb main jet check valve(or other check valve) is leaking?(let air come in from the ventury? Or it will not ? Thanks the excellent videos!
Hey, yes I disabled it, you lose that initial amount of fuel when the trigger is pulled, therefore you just run your low screw slightly richer to compensate - most carbs don’t have accelerator pumps, and thus you tune them just the same as that :)
I have done a lot of carbs over the years, but haven’t done that. NOW I need to find a carb to tear into LOL. Is it reliable? Thanks, it’s a hard thing to visualize. Take care.
Is it worth while replacing with the after market Chinese carbs or doing a rebuild on original? My thoughts are the cheap replacements are inferior what are your thoughts?
Help! I don't see the accelerator pump. I see a metal mesh in its place. I can't even remove it. Dropping some 2 stroke oil in there seems to help fill the bulb half way vs barely anything before. What should I do?
I have a Zama S68 241A carb on a BG86 blower. Ordered some 3x1mm rings but they're too big enough to fit in the bore. I was sure that's the size I needed but it seems not. Can you advise what dimensions they're supposed to be? It's such a nice blower and i got it for free so id like to keep it as it was built if possible. Thanks so much for your videos, even after years of experience in small engine work i learn something new quite often, even if it's just a different way of approaching an issue. Nice one!
@@VintageEngineRepairs hahahaha, cheers mate. I ended up cutting and gluing the big rings. Ill order some of the right ones. Was sure id used 3x1 before and saw that size mentioned in the comments on this video! Must be losing my marbles!! Thanks again fella. Much appreciated. Best reference on TH-cam, without any doubt!!
Great videos and info, thank you Question : a 2 cycle carb, off the machine, both sides of the Venturi blocked with rubber the pulse and fuel inlets plugged. If I try to pressurize I get leakage around both butterfly shafts on both sides of the carb. It’s a Zama C3 EL18. Is this normal? Thank you, Trying to learn
I have a question...can a 27cc string trimmer carb be used as a replacement for a 27cc hand held leaf blower carb..im asking before i purchase one for Craftsman 27cc hand held blower
Gday Tom. You may not see this inquiry but i was hoping you might be able to show me where the mixture screws are on a Stihl KM 94RC carby? Cheers in advance.
Yes Tom, that's what I thought. I've given it to the dealer because I didn't wish to void the warranty by pulling it to bits just yet! I'll let you know what eventuates...lol. By the way, love your videos, i could spend all day watching them, hahah.
Genius !!! Thankyou so much for this Video. I was going with your fix, but went with replacing the "O" ring, and it worked...Thankyou for GREAT Video.....
Hopefully you have an answer for me. I have the same weed Wacker with the exact same carburetor and I’ve replaced the diaphragm on both sides of the carburetor. I have done the method shown in this video and I’ve cleaned the carb out with carburetor cleaner. I have also made sure the fuel lines and fuel filter to the gas tank are clean as well. I’m still not able to pump fuel into the bowl. (which is new as well) when I pump the bowl all I hear is a whistle sound when the “fuel in” is connected but not the “return”. I’m not new to 4 stroke but I am new to 2 stroke carburetors. I did make sure to put everything back the way it came and everything was clean. The only other thing I could possibly think of (which doesn’t seem like it would be too important) is that you filled the bowl with gas and I didn’t. Do you have any idea what might be my problem? thanks for any help. Have a great day.
@@VintageEngineRepairsI finally got it up and running. The last thing I did was leave the carb in gasoline over night and then cleaned with carb cleaner. After that I assembled it and now it’s fine.
Hi, i know this is an old video and i dont expect a reply. Is there a check valve in black primer base. I was cleaning one with aerosol carb spray in my hand and felt it clear a blockage as i thought. Ended up with a jet and needle in my palm and im wondering was there a little check valve that i lost. Thanks in advance. Keith
Very clever, informative and creative ... have looked at lots of channels to try and find accelerator pump fix .. because everyone says Throw Carby away, its Cheaper (but a waste) ... PS I would have liked to have seen the symptoms prior to your fix, is all .. 👍🇦🇺
Awesome :) glad you enjoyed it! Yes that would have been good, but because it wasn’t sucking any fuel it wouldn’t have started :( thanks for watching and the feedback!
Very interesting. Currently one of my units has a bulb not filling or occasionally filling. So far it hasn't affected the performance so it's a no touch at this time.
Hi Tom, does the same testing with the fuel line sucking and pushing apply to fs120 carburetors? Reason why i ask is because I'm not seeing a point for the accelerator pump to come out if i remove the throttle rod.
If you cannot see the little hole for it either side of the carb, then no there isn’t one. If that’s the case, it could be your main nozzle check valve not sealing, your fuel filter may be out of the fuel, damaged lines of most commonly if you have taken the carb apart, the metering side gasket is leaking :) hope it helps!
They’re called Pressol oil bottles, they’re sold in the Uk, Australia and Europe! You can also visit any rc hobby shop as they use them to refil their nitro vehicles! Also try “zoom oil bottles” on eBay, they are the ones Mustie1 uses! A few options for you there :)
Hello! I have a question. I'm working on a weed eater FS38 STIHL that backfire from carburetor and burns the air filter. I just put a new carburetor in it and still doing the same. Do you have any idea of what would it be??? Thanks in advance and have a blessed day
@VintageEngineRepairs thank you ii put new prime bulb on my echo weedeater then I c gas in bulb never paid attention to the old primer bulb if it always had gas in it or not so thought I ask you so now I know thanks alot appreciate it
If this video helped you, please consider clicking on the THANKS button above to support my channel 🙌
Que sucede cuando el bombillo se vacía al rato de usar el trimmer?
Is there a way to send a donation and bypass TH-cam? I hate the thought of giving TH-cam any portion.
Hey, thanks for considering, any method, PayPal, TH-cam, patreon etc will all take a small portion sadly, but after all we get to use their platform for free which is pretty awesome :)
Compra otro carburetor
Good tips
I’ve fixed loads of chainsaws & strimmers & didn’t know there was an excelerator pump in some carbs, well done & you learn something every day.
Great to hear you learn’t something new. Always good :)
I agree!. I have "done it ALL" i thought, haha. I also refuse to be "Beaten by a Two stroke engine" and anything mechanical really. - " Can We FIX it? YES We CAN!(Bob the Builder) 🙂😇😄
@@DanielEngsvang😅
I'm VERY impressed by your knowledge of small engines. You did a wonderful job of diagnosing the problem. Thank you to taking the time and trouble to record, edit, and post this video. Much appreciated.
It’s a pleasure Kevin! Comments like yours really mean a lot to me as you are aware of the extent of the effort videos take to make. That’s awesome and thank you again!! It gives me the motivation to continue :)
This is great info that so many young techs never learn. Having said that, from a repair shop point of view its quicker and cheaper for the customer to just replace any carb that won't prime.
Spot on Scott, this isn’t something the average shop would be able to justify. It’s something I’d recommend to a home owner wanting to get their machines working again or even someone running their small engine repair business that is offering an alternative to an expensive oem carb when costs need to be kept down :)
I calculated that what I’d charge for my time to do this would be 3x cheaper than the customer buying an oem carb. That said my overheads are minimal compared to a shop of course!
@@VintageEngineRepairs BINGO!
For now it's economical to replace the card but it won't be as new anti-petrol regulations set in making all of this impossible to maintain without critical knowledge.
I have been replacing metering diaphragms, purge bulbs and fuel lines in these carburetors for years and never knew how they really worked and that they may have a fuel pump. Thanks for the detailed information.
You’re welcome! :)
You sir are a backyard university professor! Thanks for a wonderful video.
Haha that’s funny! Thanks :) glad you enjoyed the video!
Well done sir I learnt a lot and great to see a young person fixing stuff instead of throwing it away.
Thank you John, I do my best to save everything be it a beautiful vintage engine through to a fuel filter. As silly as it sounds, everything is stupidly expensive out here and if you order it online it’s 2 - 8 week wait!
Fantastic Job.
The amount of time, energy and information you placed in this video is a gift to all..
Not only did I learn a great deal, but to think on the amount of items that may be repaired / rehabbed, then placed back into service rather than being thrown away, was very inspiring to me.
Thank you so much, I really appreciate your kind words! Im pleased you enjoyed the video!
I learned about the innards of a carburetor today. I knew they are complex, even the simplest ones. Thank you for the education.
Great stuff! This video will teach you everything you’ll ever need to know about these cube carbs :) I hope you enjoy it! th-cam.com/video/_4K6dBQTeek/w-d-xo.html
This was exactly the help I needed. You are a very good teacher in addition to being a mechanic. God bless you sir.
Thank you :) glad it helped!
This was so beautiful to watch. Can you please do a video on adjusting the low and high fuel metering screws?
@@onthemudd1 hey, I have :) STIHL’S OFFICIAL 2 STROKE CARB TUNING PROCEDURE.
th-cam.com/video/UyngDl_2km0/w-d-xo.html
@@VintageEngineRepairs thanks you for this...
@@VintageEngineRepairs thanks for sharing the link with me and others
19:57 Happy Days! You are the 2-stroke genius Tom! Now I have to find all of those I just replaced with new and see if this fixes them!!
Haha thanks Kenny, I still have a lot more to learn though! Have fun with it :) if I find the o-rings I’ll send them your way. I believe they do come in a few sizes, but we’ll see!
Provided my check valve still checks, this is what's wrong with my carb. Thank you for the video. Well done!
Thank you! I’m glad it helped :)
Help please! my strimmer purge valve depresses ok but stays down for a long time! after a few pumps starts to work ok! your thoughts please?
You have a blockage somewhere :)
god that was quick!! thank you, I think the tank filter is a good starting point and work back it is 25 years old after all! did put a kit in it 2 years ago and was working well at that time! cheers, Alan.@@VintageEngineRepairs
@alanreynolds2125 you’re welcome :) yep, start from the filter and work your way towards the bulb :) you’ll find it!
You are the best. WOW. Learned more in 10 minutes, than I knew previously and I've been doing this for awhile. You are "THE PROFESSOR OF CARBURATORATION "
Hahaha thanks glad it helped!!
I have spent hours trying to solve this issue. I ended up replacing the carb but that is an admission of defeat. I will try again with my new found knowledge and win this time. Thanks for teaching me.
Glad you enjoyed it!! :)
I give myself a lot of time outs, but I eventually get it done. So don't give up, just take another break. You got this!!
Great video. I know quite a lot about carburetors, but you are definitely on another level. Thanks for sharing, and I'm going to have to check the rest of your videos. Cheers.
Hey :) great to see you over here, I love your content!
Liked, you are amazing. On my trimmer. I prime the bulb. Crank the engine and it runs perfect for maybe 3 mins then stops You have to reprime and crank again. Same thing over and over again. It's like the bulb is losing its prime. Any idea what might be happening? Haven't seen my problem discussed on the web. Thanks in advance.
Hey! Thanks for the kind words. I’d personally take the carburettor apart, put a new kit in it and maybe give it a tune. Check fuel lines and filter too 👍👍
On your diaphragm side there are two area with red wax I think ? Are you supposed to scrape and clean that up ?
Hmm do you mean covering the Welch plugs? If it’s still adhered down leave it, if it’s loose remove it :)
Yes I did remove the 2 spots where there was pink wax. Came off easily with carb cleaner and flathead.
I thought it was built up gunk but maybe was it was placed there by the factory.
Thank you for the great video
Yeah carb cleaner strips it. It’s a sealer to stop the welch plugs leaking. Now days they don’t use it due to ethanol, you should be just fine without it!
Ok thank you for clearing that up.
I'm very impressed by your knowledge of small engines. I've worked on them all my life and never knew anything about using a hand pump to pressure test the fuel system. Subscribed!
Thanks for the kind words and your sub! I’m glad you enjoyed it :)
I did not know that these carbs have an accelerator pump.
After watching your video I pulled the carb, attached a temporary line to the inlet and immersed into fuel mix. The primer bulb would not lift any fuel. I then opened the throttle shaft and applied a few drops of 30w oil past the flat to cover the accelerator pump piston, closed the throttle and tried to prime again. The bulb immediately lifted fuel and filled. This was a quick way to confirm that the O ring was at fault. Upon disassembling, the O ring was brittle and broke in 2 pieces when removing. I replaced the O ring with a generic nitrile 1mm x 3mm id. All is working as it should now.
Thank you for your clear and concise explanation.
You’re welcome mate, that’s a fantastic test you mentioned with oil, I must keep this in mind for next time, thanks for sharing!
Ive been scratching my head as to problem cause on my fs40 carb... watched this ... straight out to workshop and boom fs40 priming and running sweet!! You absolute star just saved my a fortune.
That’s fantastic! Pleased for you :)
The breakdowns of what is happening inside the carb, the drawings to understand it better, the first grade way of explaining things. This guy knows what he's talking about. Been struggling with my husqy for the weekend and this is it, the problem and the solution. You've saved me $20 on buying a new carb. You are awesome and I appreciate the very well informed explanation. Definitely subscribing after this one. Cheers mate!
Thanks mate :) glad you enjoyed it!
Rivetting stuff! Beautifully explained and videoed, even my wife watched it! Many thanks
Very kind thank you!!
I am very impressed with your knowledge of carburetors. The diagnosing of the problem and graphic illustrations are simply awesome. Thank you
Thank you! I really appreciate it!
Doesn't the vacuum from the piston/crankcase also play a part in getting fuel to the CARB. too?
That’s the only thing that gets fuel to the carburetor, yes :) the impulse, that the piston rings create, is what pumps fuel. The Venturi effect doesn’t draw the fuel into the carb as much as it does draw it out of the metering chamber haha.
Excellent description and execution of a tricky repair thanks for that insight.
Thank you for watching and commenting, I appreciate it :)
Dude! This was great. Subbed on the first vid. I love that you know the form, function, proper description and definition of even the slightest nuance of a carburator...and you can't remember to say "SUBSCRIBE"! Bloody marvelous, mate.
Haha thank you! Much appreciated :) I have always felt that people will subscribe if they like your content. No amount of asking will change that, it just gets annoying.
Excellent!I've just spent 2 hours today with this problem. Luckily i have orings.if it doesn't work,plan B,nail varnish.
I'll come tomorrow with an update.
Thanks again!
Fantastic! That’s great news :) keep me updated!
@VintageEngineRepairs I'm extremely impressed by your expert knowledge on these units. In particular your ability to perform a bespoke repair by using your understanding of the pump and sealing dynamics is a skill I'd really love to develop
I've been repairing power tools and small engines for a couple of years now but still don't fully understand carburettor operation. Are there any books or resources you used to get your knowledge up to this level?
Thank you for your kind words :) I have videos on how they work and more coming out very shortly. Start with this one :) th-cam.com/video/_4K6dBQTeek/w-d-xo.html
Thanks Tom I am doing a Stihl bower this week. . Bruce from Canada.
Great stuff Bruce! The blower is in good hands with you!
man i've watched a lot of videos on this ,this is the first one that makes sense
That’s great :) glad you enjoyed it!
Great video! I might add that if you are in the US, you will likely be dealing with ethanol in the gasoline, the alcohol in which will destroy nail polish. So use a product like Seal All that is resistant to the alcohol.
Good advise! I wasn’t sure if alcohol will dissolve nail polish, thanks for sharing g
@@VintageEngineRepairs Recently found your channel, some great info in all those video's. This a particularly helpful video explaining the possibility of an air leak at the plunger o-ring - not necessarily just the idle and main jet non-return valves allowing the purge bulb to suck air, nice work!
Since the introduction of E10 fuel here in GB, my use of nail varnish when resealing welch plugs has had to stop. Nail varnish seemed to be ok with E5 fuel. Have you noticed that the original welch plug sealant used by Zama and Walbro has been falling out and blocking jets/valves for some years - I wondered if it was being affected by the E5 fuel.
I've just done the same seal up job with nail varnish on an FS85. With the small surface area of varnish actually in contact with fuel I'm hoping the job should last for a reasonable time. We'll see...
Thanks for this ❤ I have spent countless hours on Stihl carbs trying to fix a non priming problem without realising that this accelerator pump even exists. i have seen the small screen in the repair kits and wondered what it was for but they never included an o ring 🙄 have bought a pack of 1x3mm o rings as another viewer described. No amount of carb cleaning would have solved this issue. Thanks again 🙏
Update, got to the accelerator pump then lost it as the spring launched it into the garage somewhere 😂😂
Oh no 🤣
Not many know about it :) glad it helped!
You really enjoy doing this and figuring out how to fix it
I’m impressed with your skills and knowledge 😊😊😊
I do :) thanks for watching!
Thanks so much mate. sure enough was the same issue as this video. You were walking past my place and stopped in and gave me some advice. I would love to come round and get a masterclass in 2 strokes if you were ever interested.
All good mate, you’re welcome :) it was fun and it’s always good to meet people with similar interests!
Thank you. I have a Stihl FS45 line trimmer that's just out of warranty. The bulb wouldn't fill and would remain completely dry, just like the one you demonstrated. The carb is ostensibly identical to that in your video. Pulling it apart, cleaning and reassembling it, didn't initially solve the problem. Eventually I took the cover off the fuel-pump side, as you demonstrated at 2:40. I couldn't see anything wrong with the rubber gasket and its two flapper valves (I presume). Regardless, I removed the thin rubber gasket. It was well adhered to the metal surface and I feared I was going to tear it. Anyway, no damage seemed to be done in its removal. As I could see nothing wrong, I reassembled that section and the rest.
After reassembly of the carb I put the intake pipe on my lower lip (dry) and pressed the bulb a few times. I could now feel it sucking. My fingertip wasn't sensitive enough to detect it.
I put the carb back on the line trimmer and pressed the bulb a few time. It now filled with fuel. I'm not sure what fixed it and how.
Unfortunately, the trimmer still won't start.
There was something I noticed on the metering side. The diaphragm looked lumpy, as though it had tried to expand, sort of like when paper dries after being wet. The other thing is that the bulb, once filled, resists further pumping. I don't know if that is normal.
Thank you for your video; I have liked and saved it.
Thanks for sharing! It could be your main nozzle!
Hey there, I just happen to catch this video as I was scrolling . I really like how you explain what you're doing and how it works, that makes more sense than what I've heard. The drawing helps, and the close ups with magnified. That helps when it's so small. Thank you
Thank you! I’m glad you enjoyed the video and it made sense! Sometimes it can be hard to convey everything required :)
Yes you did great, maybe speak a tad louder or have a mic closer to your mouth if possible. But yeah, I do a little small engine repair, I use TH-cam as a guide. For refreshing my skills. Most videos don't go into depth of taking it apart and explaining it more thuroughly as you have. So I'll definetly be watching more of your vidios. I took small engine course in HS. I was the only female. So we had to lock my engines in shop techs office to protect it from the guys vandaling it. But it's been 30+ years. So these videos are great refreshing for my memory lapse of time. Thank you! 😎👍
@@suzanemartin8242 so sorry to hear of how it use to be. I have heard many stories of the nonsense that use to go on back then. Thankfully times have changed and we see more woman in the repair industry and flourishing. I’m so pleased you didn’t give up. I’m always here to help when I can :)
Strange as it seems, it hasn't changed that much. The guys make it super hard to keep jobs. I aced the small engines even thou. But got crazy and went into auto body r/r. Again only female. My husband scared the poo outta those guys, after I reported my projects being damaged by vandal. That was college. I finished in the top 3 in college. But I was lucky if I was hired. Let alone they savataged my work. So in the NW, it's still very hard for a female to even get started in mechanical world. But I got burned out on fighting for employment. Had to support my kids. Couldn't keep going on. So I just enjoy it for my own good. Nice to know skills.
What would cause the bulb to be hard and not fill with fuel? After a few pushes the bulb will stay down but still no fuel. And its an Echo 2620 if that helps. About 6 months old. Im assuming the check valves under the primer bulb?
Yep! Can be the valve not letting fuel in that is blocked. Could be a stuck metering lever, very clogged screen, blocked fuel line. Something is blocked in the circuit :)
Really I have had that problem and was able to buy a o ring kit from Harbor freight and in that kit is several o rings that can be used. Just a thought if you really want to fix it for a little bit of money you can. But like the one guy said you can order a new carburetor for cheap to and the one’s I buy come with hoses and filter. Easy peasy.
The key is that they are nitrile or other petrol resistant material. If so and they fit, you’re good to go! :)
Thank you so much for showing and explaining this. I'm having a problem with a small carb with the same symptoms.
Glad you enjoyed it :) thanks for the kind words!
What a lovely video.
So pleased that there are still people around that want to help others.
Well done and thank you very much.
Thank you for the kind words :)
Top job mate. If the accelerator pump can be disabled, why do they put there in the first place?
Great question! I’m only guessing here as I can’t be certain, but with the limiters in place and the use of an accelerator pump they can have it set leaner at idle and still get good off idle acceleration. However I remove the limiters so can get past it. Notice at the end of the video I say it’s a bit lean and richen it up? That could be the requirement. Though honestly I can’t tell you, I’m simply guessing!
much appreciated! Rarely do people explain how it actually functions. I have a variation of this carb the keeps leaking fuel when i pump the bulb. Trying to understand why.
You’re welcome :) glad you enjoyed it!
Did you leave the o ring out or did you reinstall it along the plunger? Thanks for the help!
I re installed one before selling it so it was back to factory oem.
@@VintageEngineRepairs thank you
Thank you for the information. I like the way you took the time to go over the carb operation.
Thank you!
Hi thanks for the video, i like to try and fix things too theres no fun to be had with cheap chinese copy carbs unless you like retuning your machine every time you use it! I would rather a serviced genuine carb.
Can we just uae a normal rubber oring out of a cheap oring kit, or does it need to be viton or similar? Another thought might some dot3 brake fluid ir silicone spray rejuvenate/swell the oring enough to get it back to size
I have a video on rejuvenating the metering diaphragms but not o-rings. Yes they need to be viton, nitrile or the like or it will fail :)
@@VintageEngineRepairs thanks for reply :) I have seen your video on diaphragms, will try a few different things I'm about to tackle an fs45 this arvo! Maybe a very thin slice of 3.5mm od fuel line would do the trick?
Someone suggested that but I haven’t tried it :) let me know how you go. Use 3mm as that’s the original o-ring size.
Works on some things, thinking would be an idea while servicing carbs to just sit a dob of silicon spray on the check valve for the rubber to soak up, just for good measure! prevent maintenance ..or just Asking for trouble? :) what do you think
Maybe a dumb question, wouldn’t a replacement oring from an oring kit do the trick?
It depends firstly on the material, many kits are just rubber orings and will fail right away, the other is it’s a very unique size. Therefore it’s not in any kit i or anyone else I know, has found!
Speaking of holes on the body of the carb, do you know what the hole is on a br600 carb right under the high/low screws on the carb body. It sprays out fuel while running. Don't know if it's leaking while not running.
Hey, send me a picture at tomscandian@hotmail.com of the hole you’re referring to on your carburetor. Either way, no fuel should be spraying out :)
checking vids. wanted to see if on other units@@VintageEngineRepairs
I have a blower that starts and idles fine but cuts out after a couple of seconds of any significant throttle. The primer sucks about 50% air when releasing the purge bulb. I chased it through to the main nozzle not sealing. I flooded the venturi with WD40 and it finally held vacuum when purging with a blocked fuel inlet. Thought I had fixed the nozzle valve but it runs just the same as before. A main nozzle locked open should give me the opposite symptoms of rough idle and good WOT? No accelerator pump on mine just a build-in choke. I think maybe high jet is partially obstructed? Need to get one of the pacmans to get in there
Try opening both the L and H screws 1/4 of a turn and see if it improves it. An open main nozzle will give you lean symptoms at idle but be fine at full throttle.
@@VintageEngineRepairs Thanks for the reply. Tried it, still the same. Ive found a similar carb I might do a swap
Brilliantly explained video . I am amazed at your knowledge and explanations . I have several Stihl tools and to be honest I never did understand the intricacies of how a carb works . I usually replace diaphragm and gaskets , fail , and then replace carb . I have a Stihl sh86 blower that only fires once but fails to start . so I have 100 psi of compression , a good spark , replaced all carb parts and after a half day episode it still does the same . Fires once and no more . I have a new Stihl blower but would love to get this old one going just because I believe it is something very minor . Just a great video , I would love to know where you obtained all this technical info , really impressed .
Thanks for the kind words, a lot of what I have learnt has been from stihl manuals that are for
their technicians, also through research online, good mentors around me who help and and frustratingly obsessive personality that doesn’t let me give up until I understand something.
Re your 100 psi. This is actually too low for a 2 stroke ope engine to run. They say 120 is about the lowest and even then it won’t run well (if at all). The caveat here is if your compression tester is not designed for small engines, that could be why it’s low, even if the engine is good. Too much to explain in a message, but here is a video on the topic - th-cam.com/video/M6eXO6n8hhg/w-d-xo.htmlsi=7zrVpHYwLpbOuqhQ
Note on some occasions 2 stroke engines are low compression (70 psi and they’ll run) but not in outdoor power equipment. They need about 150psi.
Back again , thank you for your reply . I will study your recommended video and I think it will be prudent to check compression on the new blower . Both are Stihl sh86 models, the problem one I have for maybe 12 years .
Just for your info , the new one gave a slight problem in that the outer stop lever stuck down in the off position due to the very cold weather and the tight fitting of lever . I removed the upper hand , greased and freed out a bit and that solved the problem . The lever is designed to spring up into the start position automatically . Initially I did nor realise this and on account of hearing that the petrol quality has changed I believed that was the problem .
Anyway thank you again .@@VintageEngineRepairs
Thanks Tom, really helpful video. The nitrile O rings are a standard size so you can just buy a pack of 20 for next to nothing off Ebay rather than disabling the accelerator pump. Lovely clear explanation though and I like your shade of nail varnish.
Thank you! Yes now days I have all sizes to hand, it’s best to keep things original and replace the o-ring wherever possible. Glad you have the o-rings too! Thanks for watching and commenting :)
Hi Tom, i have just done a Stihl FS 38 same problem no priming but i have just put a Chinese carb on, there is few few videos on them type of strimmers not priming, but you have done well finding out what the problem is, the small seal is that about the same size that @henrymurawskibigdogrepair was looking for and got
Thanks Nev! I believe it’s a different size, but you never know! Yeah you can chuck a new carb on, I like the challenge of fixing it though haha.
@@VintageEngineRepairs you did very well on that one 👍👍
I think my problem is a worn o-ring on the accelerator pump piston. I've ordered some o rings, but in the mean time, I was wondering if there was a way to 'mod' the piston to reduce wear OR remove the need for the oring? The bore is 4.00mm but the piston is only 3.75mm. That alot of play for such a small size. I wonder if a better fitting pistion ( without o ring ) would work better? Another thought was to fit a second o ring at the other end of the piston to keep it square int eh bore, better. thoughts? Steve
It’s not common but you may have a worn piston. You can buy a pump piston kit :)
I've learned so much from your detailed videos, thanks for providing them to the tube!
You’re very welcome!!
Yes in joyed watching the video,great job showing and telling.if I tried that I wood miss it up I think, but thanks again for showing telling your good at it keep up the good work see ya next time see ya bye.
Thanks for watching, pleased you enjoyed it 👍
You didn’t explain that the reason the engine was bogging was because the accelerator pump was now disabled, and the carb had to be adjusted to richen up the low speed side to compensate for that lack of additional fuel upon opening the throttle.
I try my best to cover everything, but sometimes I’m on auto pilot.
Well, he had to adjust it again anyways because he had removed the adjustment screw so that he could thread in the throttle shaft and tighten up on the spring tension. Sometimes we need to try and figure out the finer details ourselves and be grateful to others for sharing the major details of their work experience in doing some stuff, whether it be mechanical or otherwise. Anyways, I worked on a Stihl weed eater and it would have cost $50 to ship a replacement carb over in a week to two.
I was wondering what channels there were under that round Welch plug on my Stihl FS38.
No matter which hole I squirt acetone through, I can't get it to come out of the Main nozzle.
If you can’t get fuel through the main nozzle, it’s likely sealed shut. Connect a tube to the H circuit through one of the drillings and close the others with your finger and blow and suck. Listen for a clicking sound. If it doesn’t click or you can’t blow, the valve is shut. It may free up in the ultrasonic cleaner
Came back to say that found this is the best video on the subject. Great! Thank you very much!
Ahh thanks mate :) I really appreciate it!
Thank your for the video! My BRAND NEW replacement carb has got to be sucking air - as evident by some bubbles in the fuel line. This video gave me a few ideas to chase after. Thanks a Bunch!
You’re welcome! If it’s an aftermarket Chinese clone, check everything inside it :)
So, what do you think caused the o ring to fail? Cheap fuel or dry rot from lack of use?
Na just age, it happens - it’s. wear item
Like your videos.I am wondering were do you get the small check valves that are in the metering area.I cannot find the parts on the diagram
Thanks! They’re known as “main nozzles” on parts lists :)
Very informative video. Think it would help if you bought a box of assorted size rubber o rings it’s got me out of trouble many times.
You won’t believe it, I had the size all along, in exactly that - a box of nitrile o-rings. I don’t know how I missed it! Thanks for watching :)
What a great video thank you but would like to know if you have to put the small screen in before the spring or just disregard it ?
It helps reduce the chances of debris mostly from the metal piston and bore getting by into the carby over time: I’d use it :)
Thanks
Thank you for the super thanks! :) much appreciated!
Hi great vid thanks. Couldn’t you replace the O ring with one out of a box of assorted O rings ? I get why the Stihl kit was cost prohibitive as so in the UK I Worked out their price strategy they simply charge £10 per part hence making a replacement carb more cost effective. Does the nail polish fix last for a long time ? Or does the fuel rot it ? Many thanks Nick
Hey loads of great questions! Over time nail varnish will dissolve in ethanol fuel. If you’re running non ethanol fuel it won’t. You can absolutely just replace the o/ring if you have one, but it has to be fuel resistant, so nitrile or viton. Just for your reference, they’re 3x1 :)
Like a pro! Great job brother! Keep up the awesome work!
Thanks mate :)
I had this exact problem today bought new fuel line and fiĺter installed them and then the purge bulb slit went and got another one and couldnt understand why it wasnt getting fuel up into the bulb thanks for making this video
Glad it helped :)
Absolutely spot on! This fixed my MS 210C first go, thanks. Great tutorial with good diagram and clear verbal explanations.
Thank you :)
Do you have a video on primer bulbs? Cause I have that issue with a Poulan and it says primer above it. It's basically doing the same thing. Not wanting to draw fuel in it
What machine is it? Cheers
@VintageEngineRepairs Poulan P3416
A master of your trade. Thank you for a real repair video!
You’re welcome, thanks for the kind words :)
Thank you for the explanation of how to repair these carbs.
You’re welcome :)
Thank you so much for all your input on the 2 cycles. I've been working on him a long time. And I just learned some new things from you. Please keep up the good work, and thank you again. Yes, i'm across the pond, hello
You’re very welcome! Glad you enjoyed it :)
Would you be able to answer a question for me. I recently brought a petrol strimmer from Sgs and never used it. I return the strimmer to them unused condition when they looked at it they said as there was fuel in the priming buld i had added fuel and attempted to start it, which i did not. My question is would there still be fuel in the buld from them testing the strimmer as surely they would have tested it first. I would really appreciate your thoughts. Many thanks.
Some companies test the before giving them to you, other times factory’s do :)
Will the vaccum system of the purge bulb work and get it full when you press it and realeased if the carb main jet check valve(or other check valve) is leaking?(let air come in from the ventury?
Or it will not ?
Thanks the excellent videos!
Correct, if the valve isn’t sealing it won’t effectively draw fuel into the bulb. Thanks for the kind words :)
@@VintageEngineRepairs thanks for the reply.its very kind and professional from your side.most you tube creators do not do it!
I try my best to answer every question I get, it’s getting harder to keep up, but ultimately I enjoy helping where I can :) thanks for the kind words!
Did you disable the accelerator pump? If so, doesn't that affect performance?? Thanks!
Hey, yes I disabled it, you lose that initial amount of fuel when the trigger is pulled, therefore you just run your low screw slightly richer to compensate - most carbs don’t have accelerator pumps, and thus you tune them just the same as that :)
I have done a lot of carbs over the years, but haven’t done that. NOW I need to find a carb to tear into LOL. Is it reliable? Thanks, it’s a hard thing to visualize. Take care.
Absolutely :) nail varnish is fuel resistant!
@@VintageEngineRepairs yeah, walbro carbs use to recommend it on the Welch plugs, not now though.
@@steveriggenbach90 yeah it won’t stand up to carb cleaner :)
@@VintageEngineRepairs didn’t know that. Thanks
Is it worth while replacing with the after market Chinese carbs or doing a rebuild on original? My thoughts are the cheap replacements are inferior what are your thoughts?
You nailed it :) Chinese clone carbs are inferior. They do work, 50% success rate in my experience, but don’t often run like oem :)
So why didn’t you replace the O-ring?
Stihl don’t sell just the o-ring, you have to buy the plunger kit for $20.
Help! I don't see the accelerator pump. I see a metal mesh in its place. I can't even remove it. Dropping some 2 stroke oil in there seems to help fill the bulb half way vs barely anything before. What should I do?
I do have a 4mix km110r. Is it different?
I’m not sure what carburetor it is, but if you google the model you can find a parts break down and if there should be one in there :)
I have a Zama S68 241A carb on a BG86 blower.
Ordered some 3x1mm rings but they're too big enough to fit in the bore.
I was sure that's the size I needed but it seems not.
Can you advise what dimensions they're supposed to be?
It's such a nice blower and i got it for free so id like to keep it as it was built if possible.
Thanks so much for your videos, even after years of experience in small engine work i learn something new quite often, even if it's just a different way of approaching an issue.
Nice one!
Hey mate, thanks for the kind words! Sure, for that machine / carb you need a 2.3mm x 0.8mm o-ring.
@@VintageEngineRepairs hahahaha, cheers mate.
I ended up cutting and gluing the big rings.
Ill order some of the right ones.
Was sure id used 3x1 before and saw that size mentioned in the comments on this video!
Must be losing my marbles!!
Thanks again fella.
Much appreciated.
Best reference on TH-cam, without any doubt!!
Great videos and info, thank you
Question : a 2 cycle carb, off the machine, both sides of the Venturi blocked with rubber the pulse and fuel inlets plugged. If I try to pressurize I get leakage around both butterfly shafts on both sides of the carb. It’s a Zama C3 EL18.
Is this normal?
Thank you, Trying to learn
Yes :) it’s not abnormal to get a very small amount of leakage there. It’s no big deal :) if it’s leaking really freely then it’s not ideal!
I have a question...can a 27cc string trimmer carb be used as a replacement for a 27cc hand held leaf blower carb..im asking before i purchase one for Craftsman 27cc hand held blower
It’s very unlikely because the linkages will be different no doubt.
Gday Tom. You may not see this inquiry but i was hoping you might be able to show me where the mixture screws are on a Stihl KM 94RC carby? Cheers in advance.
Hey! Without the make and model of carby I can’t really help but if you’re standing behind the machine they’re typically on the right.
Yes Tom, that's what I thought. I've given it to the dealer because I didn't wish to void the warranty by pulling it to bits just yet! I'll let you know what eventuates...lol. By the way, love your videos, i could spend all day watching them, hahah.
@@jimclark847 keep me updated! Glad you enjoy my content!
Genius !!! Thankyou so much for this Video. I was going with your fix, but went with replacing the "O" ring, and it worked...Thankyou for GREAT Video.....
That’s a great choice to replace the o-ring when available, good call :)
Do all these small carbs have a accelerator pump in them
No, not all, only some!
Hi, I dropped nail polish under the piston, do you think the carburetor will still work or did I manage to destroy it? 😕
Use carburetor cleaner to remove it :)
@@VintageEngineRepairs Thank you for your answer, I hope I can solve it :)
Does red gasket maker seal the piston in the accelerator?
Correct, but ideally replace the o-ring :)
Hopefully you have an answer for me. I have the same weed Wacker with the exact same carburetor and I’ve replaced the diaphragm on both sides of the carburetor. I have done the method shown in this video and I’ve cleaned the carb out with carburetor cleaner. I have also made sure the fuel lines and fuel filter to the gas tank are clean as well. I’m still not able to pump fuel into the bowl. (which is new as well) when I pump the bowl all I hear is a whistle sound when the “fuel in” is connected but not the “return”. I’m not new to 4 stroke but I am new to 2 stroke carburetors. I did make sure to put everything back the way it came and everything was clean. The only other thing I could possibly think of (which doesn’t seem like it would be too important) is that you filled the bowl with gas and I didn’t. Do you have any idea what might be my problem? thanks for any help. Have a great day.
It could be a stuck main nozzle check valve!
@@VintageEngineRepairsI finally got it up and running. The last thing I did was leave the carb in gasoline over night and then cleaned with carb cleaner. After that I assembled it and now it’s fine.
Hi, i know this is an old video and i dont expect a reply. Is there a check valve in black primer base. I was cleaning one with aerosol carb spray in my hand and felt it clear a blockage as i thought. Ended up with a jet and needle in my palm and im wondering was there a little check valve that i lost. Thanks in advance. Keith
There are check valves in the purge base. That valve will (should) have a check valve in it.
@VintageEngineRepairs as I suspected. I'm in Ireland and v hard to get parts. Genuine carb be equivalent of around 150 dollars.
Great vid again. Perhaps try to measure o-ring size and order range of viton universal o-rings. Otherwise press in a small rubber plug as alternative?
Thank you :) yes they’re 3x1 mm 👍
Very clever, informative and creative ... have looked at lots of channels to try and find accelerator pump fix .. because everyone says Throw Carby away, its Cheaper (but a waste) ...
PS I would have liked to have seen the symptoms prior to your fix, is all ..
👍🇦🇺
Awesome :) glad you enjoyed it! Yes that would have been good, but because it wasn’t sucking any fuel it wouldn’t have started :( thanks for watching and the feedback!
Very interesting. Currently one of my units has a bulb not filling or occasionally filling. So far it hasn't affected the performance so it's a no touch at this time.
Interesting! So long as it’s not affecting anything you’re probably better to leave it, you may add a problem 🤣
Hi Tom, does the same testing with the fuel line sucking and pushing apply to fs120 carburetors?
Reason why i ask is because I'm not seeing a point for the accelerator pump to come out if i remove the throttle rod.
If you cannot see the little hole for it either side of the carb, then no there isn’t one. If that’s the case, it could be your main nozzle check valve not sealing, your fuel filter may be out of the fuel, damaged lines of most commonly if you have taken the carb apart, the metering side gasket is leaking :) hope it helps!
@VintageEngineRepairs there is a white plastic plugged hole on the choke lever side, maybe that's it?
I've benefitted from a good number of your videos. Thanks very much indeed.
You’re welcome!
Where do you get your handy little squeeze bottle?
They’re called Pressol oil bottles, they’re sold in the Uk, Australia and Europe! You can also visit any rc hobby shop as they use them to refil their nitro vehicles! Also try “zoom oil bottles” on eBay, they are the ones Mustie1 uses! A few options for you there :)
Thanks
This is exactly the problem I am having with exactly the same carb!!!! How does YT know? Thanks for posting!
Crazy! Glad it helped :)
What part and location to purchase did you replace
Hey, call up your small engine shop, tell them you’re chasing the accelerator pump o-ring and tell them the make and model of carburettor you have :)
This is the most useful video. Congratulations and thank you !!!!!
You’re very welcome!
Hello! I have a question. I'm working on a weed eater FS38 STIHL that backfire from carburetor and burns the air filter. I just put a new carburetor in it and still doing the same. Do you have any idea of what would it be??? Thanks in advance and have a blessed day
Interestingly enough I find a carbon fouled spark plug causes backfiring! If not that then maybe spark timing? Check both :)
@@VintageEngineRepairs can you tell me how to do it?? Please and thank you!
Is there spose to be gas in the prime bulb all the time even when it's running
Yes :)
@VintageEngineRepairs thank you ii put new prime bulb on my echo weedeater then I c gas in bulb never paid attention to the old primer bulb if it always had gas in it or not so thought I ask you so now I know thanks alot appreciate it