1998 Yamaha Waverunner 760 won't start

[tk8636]

hello all,

I have a 98 Waverunner that won't start. This has always been an easy starting and strong running ski. The trouble began last summer. I was out running at full throttle when the engine just stopped. It took a long while to get it started to the point that I thought I would need a tow but if finally started.

It has been getting harder and harder to start this year. However, once started for the first time of the day it would continue to run and start. This weekend it really didn't want to start. We resorted to using starting fluid to get thru the weekend. Finally, it just died on the lake and I had to tow it back in. Now it will not start at all. Even with starting fluid.

- Abttery is fully charged and strong.
- It's getting both gas and oil - the plugs are wet.
- We're getting plenty of spark. What should the plug gap be for this ski?
- The compression is 75 in each cylinder. What should it be for this ski? My 1200XL compression is supposed to be 120. Is the 760 compression 120 too?

If this was a car I'd look to set the timing.

Any ideas???
Thanks in advance,
Tom

 

[The Penguin]

Re: 1998 Yamaha Waverunner 760 won't start

I think compression on a 760 should be closer to 115/120

lack of compression would explain your difficulty getting it started.

 

[kend301]

Re: 1998 Yamaha Waverunner 760 won't start

Starting fluid is a real bad idea to run off of , Pull the plugs , spray WD40 in each cylinder , turn the motor a few times and repeat 3 times , Let it sit for 2 days , do it again let it sit for 4 hrs and then redo the comp check , If it has picked up try starting it , you may have stuck the rings .