Yamaha Waveblaster 700 won't start. Has compression, fire, fuel

donzi1984

Cadet
Joined
Jul 7, 2010
Messages
7
Hello Everyone, I have a 1995 Yamaha WaveBlaster 700. It has 140 psi on each cylinder, Blue fire and won't even kick even if I spray gas down the cylinder. I pulled the flywheel and the timing marks line up and the key way is good. I also unplugged the start/stop switch and jumped it as I've heard of people having problems with them. checked reeds and replaced gaskets, Cleaned carburetor. Once in a while I'll get a puff of smoke from it but thats it.

Any help would be much appreciated. Thanks
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,286
Strange one this...if you are getting all the vitals.
Has it ran previously ? Are the plugs correct and gapped ? Battery and strong enough for a really good spark ?
Presumably it's turning over ok and fast enough ?
 

donzi1984

Cadet
Joined
Jul 7, 2010
Messages
7
New deep cycle marine battery, new fuel, did a leak down test everything was good, at least 140 psi compression with two different gauges, unhooked kill/start swith and tried jumping, pulled reeds they're like new, replaced ignition coil and wires with new plugs, tested resistance and volts on every coil in the stator and they're all within spec. Bright blue fire in center of plugs, replaced woodruff key for flywheel.
and won't even kick if I spray fuel down the cylinders...I've been around/worked on two stroke engines my whole life and I'm at a loss with this one...any help would be much appreciated. Thanks.
 

QBhoy

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Mar 10, 2016
Messages
8,286
I'm at a loss too, being honest. Before seeking expensive pro help I'd change plugs as a matter or course. Been filled by that one all too often by thinking they were just fine on inspection, but a new set saw the engine in question fire right up. Maybe a long shot, but a cheap one that's with trying.
 

QBhoy

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Joined
Mar 10, 2016
Messages
8,286
Ah...just saw you did the new plugs thing. Correct gap set ? Usually the case that the plug will come a fair way out of spec for jet skis. Usually a real general purpose plug like a ngk BR8es variety. Although some motors will run with standard gap...some older motors may be more sensitive to the gap. Had that recently with my GP800r. Was running ruff as...set the gap from standard which measured 1.4mm to the desired 0.7mm and the difference in starting, idling and too end was night and day.
 
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