Wear ring symptoms?

[lrschaefer]

I think the wear ring on my 97 Challenger needs replacing - figured I'd put the symptoms in front of the experts before chasing after it...

The boat powers up nicely up to about 4500 rpm, but doesn't quite plane off. If I push the throttle further, it's like halfway stepping on the clutch - the engine revs up but the pump loses power. If I back off, it re-engages. If I play like this with it for a while, I can eventually get it to creep up to 5000 rpm without slipping, and finally plane off. Once I plane off, it seems to run fine, staying fully engaged right up to full throttle.

I'll double check the intake with a flashlight as I've seen mentioned elsewhere in the forum. But failing that, are these the symptoms of a bad wear ring?

 

[nswillin]

Your symptoms are signs of a propulsion problem. That could be a few things. Most common problem is the wear ring. Look through the jet pump the gap between the wear ring and impeller should not exceed 1mm, bout a sheet of paper. Anything bigger than that you will need to replace the wear ring. Start there, most likely the problem. Also look at the blades on the impeller, look for dings, bent or any damage.:cheers:

 

[factory81]

That sounds like what I had for problems.

It was a neoprene seal, jet pump seal, and impeller pitch problem. Couldn't get it to plane...

 

[lrschaefer]

I got a chance to get under the boat this weekend... a little bit of weeds were stuck on the weedless grate, removed those, problem alleviated to some degree.

Clearance on wear-ring seemed OK, given limited visibility. Leading edges of impeller were somewhat banged up. I'll plan on replacing it and the wear ring as a winter project.

 

[DCKD]

Wear ring/impeller symptoms are high RPMs with low speed and decreased accelleration. If your wear ring was bad, when you give it throttle your RPMs will jump up dratically and your acceleration will be slow. Depending on how much throtle you give, you might bounce off the rev limiter. Once you get up to speed, mid-high speed responsiveness is not usually a result of a damaged wear ring, unless it is pretty bad. I hope that helps you diagnose the problem.

Matt