[:@]....drove and hour and half to the lake with a jet ski I just bought....97 ZXi (750). Took it out and it ran fine...for about 15 minutes then just died. It has ocean pro vortex arrestors with factory fuel system. would not restart...so I drove and hour and half back home and started taking some things apart...had to charge battery and then after an hour or so the ski just fired right up and ran fine...it had all new premium gas in it. I did not check spark but I noticed that my primer pump did not feel right. Does anyone have an idea. I do not want to run in out of the water too much(don't want it to overheat) if anyone has an idea of what it could be please tell me.

How long can I run the ski out of water before I damage anything? Thanks in advance

 

DONT RUN OUT OF THE WATER FOR MORE THAN 15 SECONDS OR IT WILL OVERHEAT. GET AN ADAPTER TO RUN FROM A GARDEN HOSE.

 

In order for others to help you, you need to give better description of the problem and what you exactly did.
When you said it would not start:
Did the engine crank at all?
Why do you think your old battery went bad?
How does the plugs look?
How's the compression?
As a basic approach, you need to first determine whether this is electrical, mechanical or fuel related problem.

 

Well I just bought the ski's so I thought I would talk to the salesman....he came thru for me. i took them into the Kaw dealership and the took a look at it....said it ran fine for them they then performed and compression test and found one cylinder not at specs....took the head off and found that the piston had melted in the cykinder...this blows my mind because it would start even after I got it back home(hour and some later) oh well. They are now in the process of building me another motor...and I don't have to pay for anything

 

Good for you... not having to pay.
After the repair, make sure the difference in compression of two cylinders are not more than 10% from each other. For example, if one reads 160 psi, the other should be within 160+/- 16 psi.
Also, you should find out what caused the seizure and do something about it so that it doesn't happen again - usually due to lack of oil or running too hot.