125cc GY6 won't STOP turning over...

[vagabondphx]

Hello all,

I'm new to the forum, mechanically able, but not formally trained in anything mechanical. I've been DIY repairing my little Chinese Dazon/Roketa scooter for some time now using forums and YouTube videos with reasonable success, but now I have run into some new, more difficult issues. I figure it's time to ask someone.

1) During one attempt to start the scooter, it started turning over and then just wouldn't stop. I had to disconnect the battery before it ran out of juice. If I reconnect it, it just starts continuously cranking again. I disengaged the starter button from the wiring, no change. Engaging the kill switch or the kickstand doesn't stop it either. I'm thinking a short somewhere, but I'm not even sure where to start, as this is the first real electrical problem I have had with it.

2) Issue #1 occurred while I was attempting to diagnose/fix issue #2: engine revs itself every 2-3 secs for 3-8secs each time. I have replaced the fuel petcock/vacuum and the fuel filter. I can't find any cracks in my hoses. I have adjusted the valves (.005 for both). The next step is cleaning or replacing the carburetor unless anyone else has a suggestion for something else to try first.

Thanks in advance!

[kz1000st]

The first issue of the starter cranking and cranking sounds like the starter solenoid is stuck closed and passing current to the starter. The starter button sends current to close the circuit. If the circuit closed itself the button won't affect a thing.

The second problem sound like a cracked intake manifold. Air getting in is actually slowing the engine and it revs when it recovers. It might just even be a loose manifold clamp.

[blueboy5000]

99.99999% chance it's your solenoid

[vagabondphx]

Thanks! Solenoid replaced - turning over problem fixed!

As for the revving - still working on it. The intake manifold is pristine and seals tight. Another discovery: when I turn it over to check fuel delivery, it's barely trickling out from the line coming from the petcock, but the petcock seems to get good vacuum. It's a brand new petcock, but I'm wondering if it's a faulty one - I've had bad luck with them. Anyway, I'm going to try a few more things. I'll check back with results.

[vagabondphx]

Running out of time to ride in nice weather, so instead of fooling around with a rebuild, I replaced the carburetor and for kicks gave it a new fuel petcock. Fired right up and is running SO smooth! Thanks for the tips!:yay:

[kz1000st]

Live long and Prosper.