qt50 suddon high speed then stall?


i have a 1980 qt50 that doesnt go its full speed , im not sure why ?but sometimes it picks up speed and at the end of this speed burst it stalls. does anyone know why ?

thank you


Re: qt50 suddon high speed then stall?

Sounds like you are leaning out as you run out of gas, or as fuel flow blocks. Clean your carb and fuel lines.

Re: qt50 suddon high speed then stall?

Walter Kravitz /

I agree with Tom, make sure that the vaccum from the carb to the tank is working, if your motor does not get fuel for a time, it may rev really high then die, so check all of the links and places that air needs to pass through, ie: gas cap (very common) or anything else you can think of, I dont know much about the QT50, good luck!

Re: qt50 suddon high speed then stall?


thanks for your advice, but now i have worse problems. i sprayed my carb and fuel line with carb cleaner line. i didnt see any dirt in the carb but very slight dirt in fuel line . but i didnt take the carb apart completely i just sprayed in the hole that the air filter is attached and in the other end where its attached to a metal pipe as well i sprayed in the hole where the fuel line is attached.

at first i didnt notice any difference but then i pulled the choke to see what that would do, big mistake. since then i would get more power but my engine will stop making the normal popping engine noise and make drone no power noise then continue popping. some times all i have to do to regain power is to re rev but the power varies from almost nothing to 30 to not working at all.

any suggestions?

Re: qt50 suddon high speed then stall?

It sounds like the engine is getting the carb cleaner as fuel instead of gas.

I'd recommend you spray in the same holes with starting fluid.

You also would need to tune the carb so that the engine runs high enough to stay idle. Then fine tune from there.

Another thing you can try is replacing the spark plug.

Best of luck


« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account