H50 Tecumseh surging when given throttle?

Joined
Jul 31, 2024
Messages
6
Have this tecumseh h50 I bought about 3 weeks ago.I got it running real good to my standards about a week ago. One day I took off some of the metal plates and just painted them black.I would also upgrade the fuel lines(Same lines but added a shutoff and new filter).I put all the plates back on and now the engine surges really bad.It would always surge about 20 minutes into running,I would just turn off the engine and start it back up no problem.This engine is on a minibike(Previously on a woodsplitter)Has a clean carb,vented tank,bowl and lines are filled with gas,and gas is fresh.Im blanked and have no idea what could be the reason.Any ideas?
 
Forgot to mention that the spark plug works fine(Spark is white and work fine on other engines)
 
Sounds like a plugged carb jet. Is it the original carb on it? I'd hang on to the OEM and order a replacement to try.
 
It is not the original carb.The original carb I couldn't get to run without choke.This current carb came of a tecumseh OHSK55.
 
It is not the original carb.The original carb I couldn't get to run without choke.This current carb came of a tecumseh OHSK55.
It's super common for the jets to get tiny bits of corrosion or debris in them. Lots of good youtube videos on how to disassemble and clean them with a set of torch head cleaners, etc. The OEM carbs are the best, and worth tinkering with. They are tough to find now given Tecumseh has been gone for so many years. If it's a generic aftermarket carb you have, I'd just order another one.
 
I couldn't tell you. Basically when I give it throttle it starts misfiring and sputtering real bad where the bike won't even move.It idles just fine though.
 
Have this tecumseh h50 I bought about 3 weeks ago.I got it running real good to my standards about a week ago. One day I took off some of the metal plates and just painted them black.I would also upgrade the fuel lines(Same lines but added a shutoff and new filter).I put all the plates back on and now the engine surges really bad.It would always surge about 20 minutes into running,I would just turn off the engine and start it back up no problem.This engine is on a minibike(Previously on a woodsplitter)Has a clean carb,vented tank,bowl and lines are filled with gas,and gas is fresh.Im blanked and have no idea what could be the reason. Any ideas?
I would get a new aftermarket carb and hope for the best. I had to get 2 before one worked. At less than $20 it's a gamble I'll take
 
The governor, if it uses a fan blade paddle thing, is jammed and you pinched it changing the cowl. If it's an "internal" governor you still did something to the linkage.
 
Have this tecumseh h50 I bought about 3 weeks ago.I got it running real good to my standards about a week ago. One day I took off some of the metal plates and just painted them black.I would also upgrade the fuel lines(Same lines but added a shutoff and new filter).I put all the plates back on and now the engine surges really bad.It would always surge about 20 minutes into running,I would just turn off the engine and start it back up no problem.This engine is on a minibike(Previously on a woodsplitter)Has a clean carb,vented tank,bowl and lines are filled with gas,and gas is fresh.Im blanked and have no idea what could be the reason.Any ideas?
A guy around the corner from me works on small engines and showed me a neat trick. Some jets have 3 holes some 2, not really sure why. He went to a welding supply store and picked up a welder tip cleaner tool. He runs that through the jets to make sure they're clear of debris or corrosion.
 
When you installed the fuel shut-off valve and fuel filter you generated some garbage from inside the fuel hose that ended-up in the carburetor and partially plugged a jet or fuel passage. The carb will need to be cleaned again paying special attention to clearing the jets and passageways of debris. These can be cleaned-out with a fine steel wire like the stiff wire found inside of twist ties (my favorite because they are free and readily available) or a welding tip cleaner as JTK and 97prizm suggested, then sprayed out with carb cleaner.
 
The governor, if it uses a fan blade paddle thing, is jammed and you pinched it changing the cowl. If it's an "internal" governor you still did something to the linkage.
I did mess with the flywheel and coil.I added a little coil just to power some lights underneath the flywheel.I didn't think it would cause a problem.You think this could be a reason?
 
My guess is the fuel delivery. Since you changed the fuel filter, did you use an automotive type one? They tend to be more restrictive. Is the fuel line routed so there are no low spots with good slope between the tank and carb?
 
The filter almost looks like a spinning too and pretty much just has a screen in it.Before hitting the carb,the line goes down,that is where the fuel stop is.It was like this when I first bought it
1000011604.webp
 
Back
Top Bottom