gy6 150cc dies with throttle By scooter18 (Read 6,060 times)

[scooter18]

Hello everyone,

Ive been messing with my scooter for sometime and i cant get it to ride. It starts up beautifully and idles fine, but once i give it gas it dies. I can get it up to about 4k rpm (under no load) if i give it throttle slow, but then it will die if i dont let it off the gas.

Im thinking that it is an air leak somewhere and heres why: if I choke the carb about 3/4 i can get it to rev up like normal, so maybe air is getting in from somewhere it shouldnt be? I bought a new intake manifold and took of the airbox hose to the carb, so i have narrowed it down to somewhere in the carb (if it is, in fact, an air leak). Carb has been cleaned and it has a new diaphragm, slide, and needle.

What could it be? Possibly the auto choke (enricher) or maybe the air cut valve (not too sure how that works)?

Any help or suggestions would be much appreciated.

Thanks guys

[hobbles]

Evening scooter18,
Mine was doing the exact same thing. Now yours could be an air leak like you think, mine was the carb. I just got a new one for the trike for $23 or $28 off ebay and that fixed it.

[scooter18]

Hey hobbles,
Thanks for the reply! I was thinking about doing that but I'm just as interested in finding out the root of the problem as I am in getting it in riding condition.

I'll probably end up doing that if I can't figure it out with some help from here as I have tried almost everything I can think of so far.

[hobbles]

When I cleaned my carb, I found all this in the float bowl.



I cleaned all the jets, took an air hose to it but it would still stall on me. I was lucky one time and found the sweet spot at about 4 MPH where it would run and got it home.

[scooter18]

My carb was never that dirty, thanks for the pic for refernece. I cleaned it twice making sure all the jets were clear, that's why I think it's something else. Could it be a vacuum line or maybe an exhaust leak? I'm just trying to think of all possible things before I go and buy a whole new carb

[trashtruck12172]

might think about adjusting the valves. just saying.

[cyborg]

Trash is on it ,,, I would look very carefully at all vacuum lines and intake manifold ,,, also I would look at the jets in the carb carefully as well,,, also take off the top cover to see if your diaphragm has a hole or tear in it

[scooter18]

I already had to adjust the valves because they were off and had low compression. Could they have slipped?

Everything in the carburetor is either brand new or clean except the choke and the diaphragm in the air cut valve. Could either of those be my problem? Also I don't see an air/fuel mix screw anywhere. Is there a way to adjust the ratio?


I'm gonna double check the vacuum lines and probably replace them just to be sure as well.

Thanks guys

[cyborg]

Mixture screw is behind a pressed in sheetmetal cap,,, also check the slide diaphragm on the top of the carb