96 challanger will not plain out no speed

[cacacash]

new to the boat world i just bought a 96 seadoo challanger on the first trip to the lake it felt like the boat would pull up to about 3800 rpm then the motor would rev up quickley to 7000 rpm like it was slipping . when i got home i took the jet drive off and found the fins in the impellor housing were broken so i replaced the impellor housing and re installed the unit next trip to the lake there was a minor improvement but not much impellor does not look harmed ... at a loss please help .... not a good exp for a new boat owner

 

[kustomkarl]

Did you check the wear ring and impeller while you had it apart? If the clearence is more than .040" it might need a wear ring.

Karl

 

[cacacash]

new impellor housing came with a new wear ring installed

 

[robin savell lloyd]

did you install a new neoprene seal? You seem to have a good knowledge about what you are doing so I would think that you did. But I am asking just in case. :cheers:

 

[kustomkarl]

If the seal of the pump isn't good it will cavitate too.

Karl

 

[Goddo]

Definitely a seal issue somewhere...Your pump is losing water pressure somewhere. Basically water is able to bypass the impeller. Neoprene seal was my issue. Also, check the ends of the impeller blades. If you see a lot of scarring on your new wear rings, the impellers need touching up.

 

[MobileWaterCraft]

Also check the shaft seal in the engine compartment. You may be sucking air through there= cavitation.

 

[derek]

90% of the time it is the neoprene seal. a tiny gap in front of the impeller will let it suck in air. this boat and all skis with a plastic pump support are prone to this. less noticable with skis because they are lighter and will accelerate thru the problem spot quickly.

 

[cacacash]

i found that the water return hose was leaking water in when i put the boat in the water not running. is it possible that it is sucking air thru there while the boat is moving causing a cavitation hope to find this problem soon

 

[cacacash]

i hope i called the water return line the correct thing i am talking about the plastic fitting that is screwed in the top of the impellor housing that you have to remove the hose of of to remove the impellor housing

 

[cacacash]

how do i check the shaft seal when the boat is in the water not running it does not leak

 

[cacacash]

thankyou for pointing me in the right direction

 

[timmyboy76]

how do i check the shaft seal when the boat is in the water not running it does not leak

you can fill ski/boat engine compartment just above the thru hull, with hose, while ski on trailer, then look underneath...:cheers:

 

[Goddo]

i hope i called the water return line the correct thing i am talking about the plastic fitting that is screwed in the top of the impellor housing that you have to remove the hose of of to remove the impellor housing

If you are leaking water through there its likely that your fitting is broken. I broke two this year (1 me and 1 dealer) removing the jet pump. They are plastic and don't like to be stressed in either direction.

They are called the main water inlet hose fitting. They thread into the impeller housing. I have replaced my plastic one with a stainless one and had no issues since. I would definitely keep an eye on that since the water being forced through that hose cools your engine.

I don't think that is your cavitation source. Like Derek alluded to, the seal is usually the culprit. Thanks again Derek for steering me right.