1997 kawasaki 750 sts, starts on trailer but not in water?

[sdreffs]

I just bought a 1997 Kawasaki 750, I was told the fuel lines, filters and carbs were just cleaned. I was also told the the top end was rebuilt including pistons and rings last year.
The ski starts good on trailer, when I put in the water today it started for about a minute or two, stalled and would not start. So I brought it home and checked the compression, both cylinders about 150.
I was looking on this forum and this seems to be a common problem but the fix is not always the same. Is there anything I can quickly check?
And how do I verify anything I change, do I have to put back in the water?

 

[sdreffs]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

I have the battery on a charger, I read this could cause an issue starting a jet ski under load.
Does anyone know where to get a good manual for this ski, I just bought it and don't know much about the fuel system, carburetors, troubleshooting, etc.
I checked the idle speed and it seems to be idling at around 2800 out of water.
Wouldn't a blow head gasket, exhaust gasket leak or bad timing show other signs besides not starting under load?

 

[sdreffs]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

I pulled the spark plugs and they were a little wet with gas?? And the boots have a little amount of black carbon
I plan to replace spark plugs today

 

[sdreffs]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

It looks like I could have weak spark, I checked with spark plug removed from head and attached to wire. The spark on the first cylinder was easier to see than the second. The second also had more carbon build up inside wire and boot.
How can I test to verify?
Hopefully someone with knowledge chimes in soon!!!

 

[xjdriver]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

Sounds like you have carbon tracing/tracking in the boots, you will need to replace them. As for the spark you will need an adjustable spark tester, and find the length of the gap your sparks supposed to jump.

 

[sdreffs]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

I looked at them with a flashlight and they are pretty built up with carbon. If I replace them before finding the root cause, will I ruin them again?

 

[xjdriver]

Re: 1997 kawasaki 750 sts, starts on trailer but not in water?

Just replace the boots and plugs together, should be good.