1999 Seadoo GTI 717 Compression

[Macman45]

Hi all, I am working on a project ski that I was told had no spark and that's why it would crank but not run. And sure enough, it doesn't have spark (plug grounded, NO spark). However, first thing I checked was compression. The rearward cylinder (PTO) is 120PSI. And the front (MAG) cylinder is only 60PSI.... How screwed am I? Any options? Was supposedly rebuild and he had paperwork for it...

 

[mikidymac]

That engine has something major wrong with it.
150 psi is perfect and they are done at 120 psi and typically will not start in the water. With 60 psi in one cylinder something is very wrong.

 

[k1llua]

I just had my 717 cylinders bored out because the old ones scored the shit out of them. I had 30 psi in the bad cylinder, and it wouldn't fire up..