Bad Petcock? By toxictom (Read 1,600 times)

[toxictom]

My 150 won't start like she used to. It will start if I hold the throttle wide open and crank it over for a few seconds then release the throttle and turn it over again. It won't stay running without adding some throttle. Enricher is fairly new and seems to work ok. Fuel filter doesn't look too bad. Can't find any vacuum leaks. Does this sound like a bad petcock? The fuel tank is above the engine so I am thinking the petcock isn't opening all the way and it is being gravity fed. I haven't tried sucking on vacuum line to test petcock. Thought I'd pose the question first and see what the consensus is.

Winter came overnight the other day so I'm not going to be able to ride for a few months anyways. I just wanted to store it with no issues.

[redroush00]

Bypass the petcock for a moment and put the line direct to the bowl and try. If it starts then try richening the AF a bit. The colder temps have been effecting a few scoots around town here. Make sure the battery is fully charged too.

[Alleyoop]

That are symptoms of tight valves and it is loosing compression. First thing before you mess with anything else is adjust the Valves. Set them both to .004 inchs, if still having a problem then adjust the Fuel Ratio Mixture now that it is cold the motor requires more fuel.
Alleyoop

[mikey34]

I agree with Alley on this, BUT, Since you go WOT, BEFORE IT STARTS, THEN CLOSED THROTTLE, AND THEEEEN IT WILL FINALLY START, IT COULD, be a petcock, or stuck diaphragm on the carburetor, I have had a BENT NEEDLE do that to me with similar symptoms. Most of the time it's the valves though, I know I have mine PERFECT, FIIIINALLY! I can barely touch the start button or give it a half kick, !COLD! and it starts! Every-time.... for the past 4 days.... hahaha

[straightbangin]

mikey34 petcocks are the worst cocks ever in my book. mine always gave me trouble on my first scooter and my second scooter as well even after replacing it. I decided to rebuild the way the fuel flows and just use a manual fuel shut off instead. Good luck