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By Ed Zeppeli
I picked up this quad after the previous owner couldn't get it going.
The issue is that I can't get it to fire at idle or at all.
- replaced plug. Decent blue spark. Also tested with spark tester inline.
- rebuilt the carb. PO had already bypassed vacuum lines from petcock. There's fuel at the cylinder
- Checked compression with new gauge. reads 190 psi
- cleaned all contacts I could access.
- am currently jumping with car battery. Solenoid jumpered.
- checked cam timing at TDC and adjusted valve lash
- put gas directly into cylinder to see if it will fire at least momentarily
Motor turns over well. Plug gets wet.
Motor may fire once or twice but smokes through exhaust a bit as if it's trying to fire or combusting.
This leads me to suspect timing. As mentioned I checked the flywheel mark versus cam marks. Perhaps someone has been in there before because I can't find a 'T' on the flywheel but there is a very visible paint mark which aligns with TDC position on piston. Possibly a slipped flywheel/woodruff?
Is it possible that if it had seen previous repairs, that the timing could still be off? I'm reluctant to dig into the flywheel/stator area if there's something else I could have missed but all signs point me to that area. Would a bad CDI cause spark timing to be off?
Anywhere else to diagnose incorrect spark timing?
I've scoured these forums and elsewhere but I'm posting just in case there's something I've overlooked up until now.
Thanks very much for reading!
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