Fixing A Stihl FS81 Trimmer That Starts But Won't Stay Running.
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- เผยแพร่เมื่อ 31 มี.ค. 2022
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Thanks for watching. This trimmer was given to me, but it's because it was used a dog chew toy. The problem is that it starts, but it won't stay running.
This video is meant as entertainment, always practice safety. - ยานยนต์และพาหนะ
I usually try to save the original . There is something about saving old equipment that is so satisfying. Of course I'd keep this one but that's me 🙂
Totally agree!
Agree
Ya same
Me too
I would keep it also
Great video! So glad you used it I wanted to see it in action. I always try to keep everything original if I can.
me too, thank you Billy Lawerance.
im a new subscriber and i just finally wanna say thank you for all of your helpful videos its made me want to get into small engine work and its been going great for something not very hard its a great profit flipping these small engines
Welcome aboard and thank you
Chrome plated steel handlebar, full metal housing and pull starter, she's a beauty and a keeper for sure. Given the excellent condition of the unit, I would try to keep the original carb as well.
If it were my main workhorse and the condition was not great, I'd replace the handlebar with a much lighter aluminum unit, plus it won't rust. I'd upgrade the carb for the modern purge type for ease of use. I'd also swap out the Stihl gearhead for a longer lasting unit. Yours sounds like it needs grease or replacement.
thanks, I'll have to consider that.
Excellent classic piece of equipment. Good save!
It sure is!
Really enjoy watching your video. Thx for all the information.
Thanks for watching!
I would try to save the original carb. After all, it IS a Stihl! Not many mention the stiffness of the flaps, just make sure they are flush. Thanks for the tip. That trimmer is in rough shape, but it will get the job done! Have a great day!
Great point!
Hey, I'm just gonna pet you know that the stihl carburetor is made by Warlboro
Nice machine! Worth the time put into it!!!
It sure is!
I was given a fs 88 an I really like it it's a older trimmer but works real well
I like that generation of Stihl too.
Nice fix. Thanks
No problem 👍
have the same one and love everything about it
nice
The spark screens on these old ones are super fine mesh. About twice as fine as modern Stihl equipment. Very restrictive even when they’re not clogged. Better for the machine to remove it entirely. Retains less heat and offers a little more peak power. I have an fs86 which is the same family as your 81. Had to re do the piston rings and carb kit, now I’m waiting on a replacement gas tank. Not broken, but same as your gas cap, the O-ring is bad. Rather than replace that and have the tank crack soon since it’s very old I decided that replacement was the best option. If you plan to use yours for years to come, I’d reccomend getting a Stihl shoulder strap to save your arms while using it
thank you A Egan!
Great video, I would try and save the original carb whenever possible, nice work!
Great point, thank you WildeFox
That right there is some old gold. Engine runs well. When you get another Stihl, you can replace the busted parts.
what is the solution you soked the diaphram in ?????
@@scottmiller2278 The old way was to soak rubber parts in brake fluid.
brake fluid.
you got it.
I like the blocky look to the engine housing. It looks classic
I agree
Because the unit is an expensive one and over all it seems to be in good condition I would try to keep the carb original. I would do that with any expensive model regardless of brand. Beyond that if it is going to be just used as a trimmer I would use an aftermarket carb. to get it up and running. This is one of those trimmers that should be like a collectors model. Thanks for the video.
you make a really good point.
I'd save the carb because we have a dealer about 1/2 mile away for kits but parts are outragos high. Another carb for the 440 is $145 plus and I still wouldn't be able to adjust the high speed like I'd like to so I just use what I have. I used the tri-cornered blade for grass and briers but a carbide saw blade for bigger stuff. And yes, it takes a while for those to get wound up but they sure do a fine job. I used a shoulder strap on mine because it gets really interesting trying to hold it up by the handlebars in a thicket. Thanks and Blessings!
thank you Lewie McNeely
@@HomeGaragechannel U2!
I put some tB 1184 on grommets to keep them from leaking. Clean tank area around the grommet and grommet with break cleaner, first. A thin coat is all that is needed. Allow to cure overnight before inserting the new fuel line. Anytime I replace a fuel line it gets a new fuel filter. If I take down a carb it gets a new oem rebuild kit - Walbro or Zama and not a cheap Chinese set.
thank you for that information
I would use a stepper drill to hog out metal around the perimeter of the blade for weight reduction
And it is best practice to change the grease in the head and grease the upper bearing after the clutch. Grease tends to turn into resin after a few years.
I appreciate the tip, It's definitely something I need to do before I use it.
Make sure to check out the brush blade for stress crack's that style of carb is the same as my br 400 sthil blower
ah Yes, I'll do that, thank you Robert Mailhos.
@@HomeGaragechannel you are welcome young man 😎👍
Hello Home garage yesterday is my birthday I will fix everything that you said in your video
Happy birthday!
I will save the original cab. Awesome repair. 👍🙏👍🙏👍🙏
me too , and thank you RayFpv.
@@HomeGaragechannelI just got one of there and will like to start the engine. How many turns in the H and L to get it running so I could tune it. Should I do one whole turn on both?
You can put some Tb1184 on the grommet and it will seal it if you cannot get a new grommet.
thank you John Clarke.
Hey i have this exact trimmer model and i put a turbo on it I have two of them
my grandfather has the same scythe and it still runs well for its age

That's pretty cool, thank you Karl for the comment.
It looks like a strong and heavy piece of equipment bro
very much too, thank you Ramadin Sookhoo.
Hey, just wondering, do you blow though the fuel filters before you re use them to make sure they are not clogged?
only if they have 2 stroke oil, caked in it.
If the parts are there to rebuild the original carb I would also. Especially when u see a sthil stamp on it
you are absolutely right about that.
Originally to assist starting, the switch had a Start Position which held throttle open a tad, just like their chainsaws . Mine starts within 2 pulls utilizing that
nice thanks for the information
@@HomeGaragechannel oh and great video , my outer filter was missing and presumed it may have been foam, so visited here to confirm 😊 Seems mine has disintegrated too
that was hilarious, you squeezed the trigger and it died quicker then i thought it would :D
it happens sometimes.
15:49 You can sharpen that blade. However it is pretty worn out, you may want to buy a new grass blade (that is what it is called at Stihl). There are also Saw Blades for that machine, saw blades which cut up to about two inch saplings
I'll have to look into, thank you MrCarl312.
I would rekit the carburetor & what solution do you use to rejuvenate the gaskets ?
I have heard of people using brake fluid to rejuvenate them !
it's brake fluid
The original carb is fine, you needed to adjust the high end fuel. Since the engine idles, but dies out under throttle, the air-fuel mixture is incorrect.
What solution did you use to rejuvenate the parts?
Also link for the metering diaphragm, takes you to a different item.
it was brake fluid, and I've contacted Amazon about it, The picture are wrong but the description is correct for the metering diaphragm. I changed the link to a different one thought
Save the old Walbro. Good video.
yes very good advice, thank you MrRmh3481
If you oder a new carby then check the nipple of the fuel line to see if it’s cracked the simptomes of it is that it won’t stay running and no matter what you do to the adjuster screws it still runs bad and you will notice that you see bubbles coming near where the fuel line attaches to the carb
thanks for the tip
You saved the carb..most of the ones i work on need a carb. Guess you got lucky..looks like it's not rated for the brus to cutting blade..I've seen that a few times..the customer want's a brush cutter but his machine is not rated..they don't want to hear that..what can i say....yours was a pretty easy fix for not running that i was suprised..what did you soak it in ? Good to see you again..see you on the next one Cheers 🍺🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸
thank you Rodney Brand, it was brake fluid
@@HomeGaragechannel i should've known..I've tried armor all..silicone...tire shine... dawn dish detergent ..i just gave up..ill try brake fluid ..thank you for replying back..i like your videos such great detail thanks again..Cheers 🍺🇺🇸🇺🇸🇺🇸🇺🇸
any time Rodney Brand.
I always save the original carb on everything I restore. I hate when people take the easy route and install a cheap chinese knock off and throw the OEM away. Great job on the repair. 👍👍
thank you Livin' The Dream!
This is the exact same thing that happened to me with my New total trimmer I tried to adjust the carb but it still didn't stay normal then we took it to a mechanic and Sayed the carb was not good so he changed it to a new one and until now it's working how it's supposed to work
*Good morning again*
It’s evening here
@@LeoMAUW someone chanted evening
You should get a bore scope so when you get stuff like this you can look in side
that's a good idea
I would have ordered a complete rebuild kit and just rebuilt it, because some of the aftermarket carburetors are kind of hit and miss. Some work, and some don't.
you make a good point
You said you soak the gaskets in liquid. What kind of liquid? I may have missed it.
Thanks, good presentation.
no I did not mention it, on purpose, but since you asked, it's brake fluid.
Good to know. Do you still recommend doing this?
not really, I only use it as a last ditch effort.
well from my view i would try saving and rebuilding the original carburetor part with new hardware to match and if no good after doing it properly well then that,s when i would consider replacing it.
make sense, thank you Patrick Stapleton .
@@HomeGaragechannel my pleasure mate stay safe.
I have new cheap carbs ready for use, but I want to try to grab the gaskets out of them to restore the original carbs...
absolutely
Replacement carburetor new with prime bulb on,easy to start
agreed
Bro you should sell equipment that you fix I would totally buy because I know the person that worked on it knows what he’s doing
Actually -- I do, I just don't always mention, that I'm selling them.
@@HomeGaragechannel where do you sell them?
What is the solution you use to soften a diaphragm?
automotive brake fluid DOT3 or 4.
What years was this model made? I can’t find any info on it.
I'll have to get it out to look
Hey. I have the same trimmer and have carb issues. I tore it apart and cleaned all orifices with carb cleaner and a wire. When i pulled the needle when i pulled the diaphram and think i got the tenson on the screw wrong that holds the needle down. Any tips on how it should operate? I have it loose to where it moves freely. Like a quarter turn from snug.
Something is wrong, that screw should be snug, and still be able to move.
@@HomeGaragechannel ok i that explains the flooding.
have you been able to find a replacement carb for sale? that would be my next plan for it.
What brand after market carb do you use?
I don't have a specific brand that I choose
Knowing how I do things, I would have bought a kit or new carb. I do not want to have to go back and fix it again. Have good days!
Thanks, you too!
Save the original. Interested in the solution mix you use. What’s in it. Have a little project coming up.
thank you Dion Summers.
I would drill a few holes in the blade to lessen the weight. Don’t go nuts just a few here and there, not enough to weaken the metal just enough to lessen weight of it.
interesting idea.
I would save it. I would also purchase a push button momentary switch to the cover to ground the coil for a kill switch. I would keep it and invest in a new blade.
that's a good idea, however, I would like to put it back to stock too.
This is the first time I’ve ever seen a boot for the spark plug completely missing
I know right, it's quite a shocking experience.
Do you plan on replacing the handles?
no not unless I need to. I might modify them, so they don't scratch me when I handle it.
I have the Same one.
nice
what is that solution you soak the diaphragm in?
it's brake fluid
What electric screwdriver are you using? Thanks.
I didn't see which one I was using but it was more than likely my milwaukee
Hey I have a question, what is that silution your using? Is it some kind of oil or what?
it's either a citrus based cleaner from LA, or just soapy water.
@@HomeGaragechannel ok thanks so much.. and I really enjoy your videos you actually know what your doing.
I appreciate your time as well.
What is the rejuvinating solution for the diafrag.
brake fluid.
@@HomeGaragechannel Thanks
What solution did you place the rubber in?
brake fluid
@@HomeGaragechannel I've tried using brake fluid, but it never seemed to do much restoring - even after months of submersion. Is there a particular type of brake fluid you use that I should try?
really? that's strange. Nope it's just DOT 3 brake fluid for your car
I purchased this model without the handle bars (standard string trimmer version) in non-running condition. I followed some of your procedures by adding a little gas in the spark plug hole, then draining the old fuel and adding fresh. I got lucky as it started and runs well. No unpleasant surprises as is sometimes the case when buying non-running machines. This is a somewhat heavy but a solid capable machine. I can see why many like Stihl.
nice work!
That blade is scary 😳
yes it is.
Which lotion r use to
24hr meatring diafram dip
brake fluid.
@@HomeGaragechannel thanks sir
no problem
I would of tried to save the old carb. If that didn’t work then I would of replaced it.
I would too.
Try to keep it o.e.m. as much as possible.! It looks like if has earned it!
thank you Joe Ortiz.
Save the carb, it's a quality built machine
thank you Andrew Orli
When are you going to fix your Stihl super chainsaw?
I haven't decided when yet, It depends on the cost for he parts.
It was the original Walbro carb! Save it!
you are correct, thank you Kaleb Brown.
In this case rejuvenate The carburettor 😀🇦🇺
absolutely
That's just a Walboro carb, can't you just easily get a rebuild kit for that? A K10-WAT will likely have what you need, easy to find on Amazon for less than $20 CDN.
probably
that trimmer looks old, I have a sthil chainsaw, and it was sitting in my grandma's garage for 10 years with no gas in at, so I threw some gas in it and it fired on the third pull. I did nothing to it other than putting Gass in it, and it's been running great and I still haven't done anything to it
that's a quality machine there, thank you Warrens Outdoors
I have heard that amazon carburetors are cheap quality and that is a shame, i am not sure that is worth it even for the price..
probably
Definitely need a new blade
yes, this blade is pretty much gone
That blade needs to be either sharpened or replaced. Its pretty dull.
Yes it's terribly dull.
Bro the engine sounds like a Chinese weed eater...
really? or does the Chinese weed eater sound like a stihl?
When all the Chinese weed eater on full speed it's has a kind of a screaming noise so that I could know it's sounds like a Chinese wacker :)
Mine would shut off becuase the head always spins
that's interesting, is it like the one in the video?
@@HomeGaragechannel it doesn’t have a clutch lol
Get rid of that cutting blade and fit a genuine stihl line trimmer head.
I don't think that blade is original anyways.
You make a good point.
seeing just how little the warp can be on the diofram thing in the carb, tells me that ive been over looking that to be a common issue when i get one of my 2cycles acting up on me. currently my blower is running for about 30 seconds and shutting back off on me. if i give it throttle, it shuts it off faster...wander now, that it too just needs that diofrm thing replaced or fixt if it can be. i just got another carb in for it though...so im kinda not feeling like messing with that diofram in the original carb. but i know i did just run the hell out of this blower for 7 years straight...so lets see how long this after market junk will last. i give it 2 years max. hoping for at least one year though lol
yes the diaphragm needs to be extremely flexible with no wrinkles. And yes it was hard lesson for me as well. For years, I didn't know why I was having carb issues until I started replacing the diaphragm.
Can you please
Share how you made the solution?
sure, the solution is just automotive brake fluid.
@@HomeGaragechannel thank you bud! I have a husqvarna super strong and heavy trimmer… the carb floods any ideas what to look for?
is it flooding when trying to start it?
If so, can you tell me exactly the step you use to start it?
I just want to make sure you're not pulling the rope
more than 2 or 3 times, when fully choked.