Troubleshooting a Huasheng 4-stroke Engine

Also how would I tune it once the brass plug is out? How would the process look like?
 
I removed the brass plug too. It was fairly simply and allows adjustment now. A lot easier than fitting a different style of carburetor. Turn the screw to adjust the rpm where you like it.
 
I removed the brass plug too. It was fairly simply and allows adjustment now. A lot easier than fitting a different style of carburetor. Turn the screw to adjust the rpm where you like it.

Glad to hear it! I'll be giving it a try a little later in the day. I'll post the results.
 
Turn screw clockwise for leaner, counter clockwise for richer. Try setting it with the idle rpm screw (the black plastic one) set at about 1 1/2 turns in and turn the screw behind the plug all the way clockwise then turn counter clockwise 2-2 1/2 turns. Do minor tweaking on this screw till its where you like. If you gotta turn the rpm screw in a bunch then you are too rich.
 
Idk why I haven't suggested it yet, but you let it sit for 2 years. Perhaps old gas gummed up your carb. Get carb cleaner and take your carb apart. Unscrew the idle jet and spray in there. Remove the float bowl and spray in every hole you find including the one the float plunger covers. Try not to lose any parts, do it in a bright clean area.
 
I have had the same problems as you. My Huasheng 49cc would have a hard time starting and the idle would waver all over the place. I definitely recommend cleaning the carb as old gas gums up this carb fairly quickly. I would look into replacing that carb with an NT carb. I replaced mine a few weeks ago and the idling is super smooth. I even gained some acceleration as the older carb would bog down before starting to accelerate. I have had great success with the NT carb and have never looked back. Also, I would make sure your valves are adjusted as well .004" intake and .006" exhaust. My valves were pretty off from the factory and my engine ran so much better after that as well.
 
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UPDATE: Ugh beat and tired lol! Has not been fun lately getting this thing to try to run. OK so here's the breakdown I did everything CrazyDan recommended and a few others. Got the brass plug out and lo-and-behold there's a A/F mixture screw there. So I do the tuning instructions that CrazyDan recommends and.......no luck. I was spraying starting fluid into the carb and the engine would fire briefly but never stay running. Would only run for the amount of starting fluid sprayed into the carb. So here I am now, beat and tired lol. My arm is sore from pulling the pull start so many times and doing changes to the idle screw (black one) and the A/F mixture screw. I tried every possible combination for tuning and no luck. Not sure what to do at this point just feel frustrated and beat :/.
 
Idk why I haven't suggested it yet, but you let it sit for 2 years. Perhaps old gas gummed up your carb. Get carb cleaner and take your carb apart. Unscrew the idle jet and spray in there. Remove the float bowl and spray in every hole you find including the one the float plunger covers. Try not to lose any parts, do it in a bright clean area.

That was one of the first things I did BTW, think I had it in the original post. Took the whole carb apart and got every nook and cranny clean. There was a lot of lacquer from the old fuel and gunk! Glad I did that deep cleaning.
 
I have had the same problems as you. My Huasheng 49cc would have a hard time starting and the idle would waver all over the place. I definitely recommend cleaning the carb as old gas gums up this carb fairly quickly. I would look into replacing that carb with an NT carb. I replaced mine a few weeks ago and the idling is super smooth. I even gained some acceleration as the older carb would bog down before starting to accelerate. I have had great success with the NT carb and have never looked back. Also, I would make sure your valves are adjusted as well .004" intake and .006" exhaust. My valves were pretty off from the factory and my engine ran so much better after that as well.

I've done a deep carb clean, one of the first things I did. There was so much lacquer from the old fuel in the carb and gunk that I'm surprised it didn't run previously. But now I'm kinda stumped as to why it's not wanting to run. Even after tuning it and trying to kick start it with some starting fluid.

Thanks for the recommendation for the NT carb. I'll have to take a look at it, looks like a safe bet if you had success with it. I'm just tired of messing with this carb and not having the engine fire.

As for the valves I've never looked into doing an adjustment on them, I don't know if that might be the issue. But the motor hasn't run that much since I've gotten it. Probably like a total of 2 hours at most.

I'll definitely look into the NT carb though!
 
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