95 GTX seems like pump is "slipping"

[Texas Guy]

95 GTX runs well except this weekend I noticed when I ease into throttle the pump, enging rpm's and water push all seem normal and I get up to the normal + or - 43 mph. However when I try to accelerate hard and fast it sounds like, or maybe feels like the pump is slipping and the engine rev's higher untill the boat speed picks up and then things seem normal again. So the problem appears to be "slipping" under Hard Acceleration.

Any ideas?

Thanks

 

[roneagan@cfl.rr.com]

You need to check the clearence on the wear ring.. It should be around 1mm between the impeller and the ring.. If there is to much space you will not produce the needed thrust for good acceleration.. The pump is direct drive so there is nothing like a cluctch to slip..

 

[gutterboy2ca]

yupp, get yourself a set of feeler guages,check wear ring,and blades on prop for bends dents,ect.

 

[Texas Guy]

Well, I can see some dings in the leading edge of the impeller and I guess I'll have to find some feeler gauges.

Is this feeling of not hooking up and engine revving a symptom of too much room between the impeller and the ring. I know that there has never been any maint done to the impeller or the wear ring. Since this a 95 GTX is it an easy pump assembly to remove?

 

[hermie]

also check your motor mounts see if you can lift up on the motor at all

if they are broke or pulled out of the hull the motor will move, when you gas it, and let the splines of the drive shaft pull out of the pto and slip like you are describing. Eventually it will strip the pto and shaft splines. Another easy way to check is take the cover off the shaft/pto and if the rubber boot is all tore up or missing that means the shaft has spun in the pto.

 

[seadoosnipe]

Age and cavitation....

This is a sign of slight cavitation. Its really not unusual, especially for a ski almost 15 years old.

If your getting the speeds you say, then your wearing ring is probably o.k. When the wearing ring is shot, your motor is running but the ski isn't going anywhere. As the ring begins to wear, you begin to lose RPM.

If your stator vanes are knicked or your impeller has a few dings in it, this is the most often cause of what your feeling in the acceleration. When you make a sharp turn, it'll likely do it there too.

The dings and small knicks cause the water to flow with a bit of turbulence. This is where you pick up slight cavitation. Personally, I would not worry about it until it gets worse.

I would consider popping off the nozzle and bucket to check your pump oil. If you have no idea when it's been maintained, I would be doing this ASAP. This is the quickest way to kill your pump.........You can use the search engine to find info on it. Use keywords like pump oil, changing pump oil, impeller removal........:cheers:

 

[Texas Guy]

Hey Hey Hey! Check this out, Upon closer inspection ... Thar she blows! Part of the wear ring is Gone!! As they say in Texas, that might could do it.

One Pump Assembly Comming Out!!

I've got a great picture if I can figure out how to post it ...

 

[Texas Guy]

If I did this right the picture of the damaged wear ring is below.

 

[jhjesse]

Texas,
Looks like you found your problem. New wear ring $30 and while you are at it check the pump bearings and change the gear oil in the pump. :hurray:

 

[timmyboy76]

i see nut'n wong with dat picture/wear ring....?

think its the crap, wrtapped around the shaft.