4th of July fail

[SeaSparks]

So this past 4th of July I had the unfortunate experience of sucking a fist sized chunk of asphalt into the jet pump of my 98 GSX Limited at an unusually low lake. At the time I was about 150-200ft from shore and hit an area about 2ft deep unknowingly at idle and the ski rumbled and shut off. After a small panic attack I was able to get off and find the chunk and remove it. It was hard to start and having no option of being towed back the almost mile trip to the ramp I rode back in after it finally started. It died once more about half way but I did make it in. When I got home (again in a small panic attack) I checked and double checked the pump for any more obstructions and could not find any. My once near perfect impeller does have a few slight nicks in it but nothing too major. I removed the pump nozzle and replaced the pump oil on the advice of a local shop but after putting everything back together it will not idle above 1500 on the trailer and does not idle as smooth as before. Before this problem the ski ran great with no issues at all and idled about 2800 on the trailer and about 1200 in the water. The worst part is that this is a brand new engine still running break in pre-mix and the injection system with only about 5 hrs on it. So I am hoping I have not damaged the motor. If there is anything anyone knows to check in addition to the jet pump after something like this any help is greatly appreciated. Thanks.:banghead:

 

[LouDoo]

I doubt that you damaged the motor, the first thing I would check is the drive shaft. Remove the pump, remove the drive shaft and see if it's bent, generally just roll it on a flat surface.

Lou

 

[SeaSparks]

Ok, removed the pump and drive shaft. The shaft is straight. Is it possible that this could have damaged the bearings in the pump? There is a slight scraping sound when I turn the impeller by hand.

 

[LouDoo]

It's possible, I think I would check the impeller shaft, also the impeller itself, does it seem to be dragging on the wear ring?

Lou

 

[SeaSparks]

No, no dragging at all. It has less than .5mm clearance against the wear ring all the way around which should be within spec. There is noticeable play front to back and a little wobble up-down and left-right. I am not experienced enough to know if this is normal. Looks like a pump tear down is in order.

 

[LouDoo]

The play front to back is normal, the wobble is not.

Lou

 

[SeaSparks]

Ok, thanks LouDoo. Looks like I will be replacing most of the pump components and hopefully that will correct all the issues.

 

[470]

You could pull the plugs and put wooden dowels in the plug holes and make sure the crank phasing is correct. They need to be 180º apart.