@@VintageEngineRepairs it's a trick I use on nitro model engines to seal troublesome needle valves, it works amazingly well if you can get the correct size hose
Thanks for showing us ..I deal with a lot of small carbs ..some are difficult and can't find the exact replacement carbs iv probably threw away and ordered new carbs and should have checked that instead and saved me money
I ordered and replaced the o ring once, worked great. It's gotta be a common FS-45/55 killer. The two I've worked on both had bad o rings. The second one, for fun and to avoid the pain of sourcing the o-ring again, I tried the epoxy method. I either used too much epoxy (it squeezed through the channel leading to the primer/fuel assembly), or the carb had other issues. Fuel flow stopped. I drilled a new fuel channel, which worked, though it became unreliable and tended to flood I believe, so I'll be replacing the carb (good experiment, anyway!).
Yes :) it depends on the carb and where the drillings are! If in any doubt, and you have access to the o-rings, just replace them :) if you know you won’t block any essential channels, you have nothing to lose. Though yes epoxy can drip where you don’t want it. Thanks for sharing!
I have a Walbro carb leaking fuel after about 15 bulb presses. I did the pressure test as you showed here and it holds 10 psi and holds its new psi under pressure when pressing the bulb. Unlike yours, my carb is not constantly leaking fuel like a stuck open needle would, it instead leaks when the bulb is pressed through the little small holes in the venturi. Any idea what it could be? Also nice explanation!
@@VintageEngineRepairs thanks, its been working fine since I did that. I pressed it closed a handful of times to return it to its natural shape. Is there a way to test for this problem like a pressure test for the needle or is this just something you learn after working on many machines? Sorry for the long comments, i enjoy working on these machines and im trying to learn as much as I can!
There is a zama carb on my stihl 192 chainsaw. When I rev the engine fuel squirts out of the intake. Could this be the reason or is there another issue?
Reason for what sorry? Typically that’s either a blocked exhaust screen or worn piston skirt. It shouldn’t be blowing back. If you come across this on an engine with a reed valve, the reed may not be sealing.
@@VintageEngineRepairs Well, there's a thought lol. I buy so much online that I don't think of local shops. I don't think they like to sell parts here because they want the repair business.
Stihl only sell parts to their brick and mortar shop, never online. You can occasionally get NOS parts or if someone buys in bulk and sells, but typically the only place I’d suggest is your local b&m store
@@VintageEngineRepairs Well, I tested it this way. I dipped it in water just the hole "where the O-ring is" and the fuel intake nozzle, and it would draw water into the primer bulb but wouldn't pull water through the nozzle by itself. Thx for responding, love your fixes !!
@@bumblbesss Yes, this worn o-ring on the accelerator piston in the carburetor causes fuel not to be drawn into the priming pump bulb, but this worn o-ring on the accelerator piston in the carburetor does not cause the carburetor to flood!
You’ve got a great knack in explaining things, great stuff
Thanks Al!
I have learned so many tricks from you.
👍🏻👍🏻
Best explanation I've seen! Well done Sir!
Thanks Ray :)
That was a unique fix. Good show.
Thanks Bill, seems to have worked well :)
@@VintageEngineRepairs Cool. It's all about results
Nice job Mate! Most people would just put on a Chinesium Carby! Great to see the cause of the flooding and the repair (sans o-ring).
Thanks Kenny :) I like digging in to a problem, I’ve yet to come across a carb I haven’t been able save! There is normally a work around too haha.
That Zama carb is made in China 🙊
Good job Tom, useful information for sure. 👍
Thanks John, much appreciated mate.
Anytime brother
Hey mate good vid! for the oring try cutting a very thin slice of 3mm fuel line and slide that over it
Very interesting! Have you tried it?
@@VintageEngineRepairs it's a trick I use on nitro model engines to seal troublesome needle valves, it works amazingly well if you can get the correct size hose
@@VintageEngineRepairs I do that and itworks like charm, i use silicon line
Hello, Great video. Can you explain what the accelerator pump does? Does it contain any drill holes in the carb that have access to it?
It gives you a squirt of fuel upon acceleration to help reduce lean bog.
Thanks for showing us ..I deal with a lot of small carbs ..some are difficult and can't find the exact replacement carbs iv probably threw away and ordered new carbs and should have checked that instead and saved me money
Glad you enjoyed it Jay 👍
I ordered and replaced the o ring once, worked great. It's gotta be a common FS-45/55 killer. The two I've worked on both had bad o rings. The second one, for fun and to avoid the pain of sourcing the o-ring again, I tried the epoxy method. I either used too much epoxy (it squeezed through the channel leading to the primer/fuel assembly), or the carb had other issues. Fuel flow stopped. I drilled a new fuel channel, which worked, though it became unreliable and tended to flood I believe, so I'll be replacing the carb (good experiment, anyway!).
Yes :) it depends on the carb and where the drillings are! If in any doubt, and you have access to the o-rings, just replace them :) if you know you won’t block any essential channels, you have nothing to lose. Though yes epoxy can drip where you don’t want it. Thanks for sharing!
thanks it helps a lot
You’re welcome :)
Excellent.
I have a Walbro carb leaking fuel after about 15 bulb presses. I did the pressure test as you showed here and it holds 10 psi and holds its new psi under pressure when pressing the bulb. Unlike yours, my carb is not constantly leaking fuel like a stuck open needle would, it instead leaks when the bulb is pressed through the little small holes in the venturi. Any idea what it could be? Also nice explanation!
Yeah, you need to remove that little duckbill valve under the purge bulb and press it back in fully. Hope this helps.
@@VintageEngineRepairs thanks, its been working fine since I did that. I pressed it closed a handful of times to return it to its natural shape. Is there a way to test for this problem like a pressure test for the needle or is this just something you learn after working on many machines? Sorry for the long comments, i enjoy working on these machines and im trying to learn as much as I can!
There is a zama carb on my stihl 192 chainsaw. When I rev the engine fuel squirts out of the intake. Could this be the reason or is there another issue?
Reason for what sorry?
Typically that’s either a blocked exhaust screen or worn piston skirt. It shouldn’t be blowing back. If you come across this on an engine with a reed valve, the reed may not be sealing.
Where do you get the O rings? I don't have a punch. I found the part number for the O ring but no one sells them
Go to your local stihl dealer 👍
@@VintageEngineRepairs Well, there's a thought lol. I buy so much online that I don't think of local shops. I don't think they like to sell parts here because they want the repair business.
Stihl only sell parts to their brick and mortar shop, never online. You can occasionally get NOS parts or if someone buys in bulk and sells, but typically the only place I’d suggest is your local b&m store
Very nice sir
Thank you!,
Nice hack Tom 👍
Thanks Bill!
I forgot to ask, will this O-Ring cause it not to draw fuel into the primer bulb?
Yes, if it’s leaking bad you can suck air in to the purge bulb. Also if the main nozzle is leaking or your gasket is leaking too.
@@VintageEngineRepairs Well, I tested it this way. I dipped it in water just the hole "where the O-ring is" and the fuel intake nozzle, and it would draw water into the primer bulb
but wouldn't pull water through the nozzle by itself. Thx for responding, love your fixes !!
@@bumblbesss Yes, this worn o-ring on the accelerator piston in the carburetor causes fuel not to be drawn into the priming pump bulb, but this worn o-ring on the accelerator piston in the carburetor does not cause the carburetor to flood!
That accelerater pump will shoot out if you don’t know it’s there, it happened to me.
Yep keep your thumb over it