Wear Ring seems to have melted on my 140mm GTS pump...

[IDoSeaDoo]

Doesn't seem like typical wear to me... I was riding around in some heavy debris water (trying to avoid most of it) and noticed it cavitating. Knowing this to be a sure sign of a clogged grate, I pulled over and sure enough: I had to unplug the intake grate. After that, I thought I was home-free, but the cavitation was still pretty bad, so I called it day. I pulled a few more small sticks out that day, but nothing major. Yesterday I took it off and it seems that the wear ring expanded and melted around the impeller. There is hardly ANY clearance on a 20yr old wear ring... has this happened to anyone b4?

 

[Strizzo]

going to need pics of this one. sounds like you didn't get all the stuff out of the impeller and something chewed the ring up, or threw the balance off enough for the impeller to eat the ring.

 

[LouDoo]

If you got 20 years on a wear ring that must be some kind of record. Like Strizzo said we need a picture, but I'm guessing the wear ring has just deteriorated from age.

Lou

 

[IDoSeaDoo]

That would be understandable, but what I'm seeing is the ring actually EXPANDED to make a perfect fit around the impeller. It actually seized it a little (it was hard to turn the PTO). I'll have to take some pics and post em tonight. It's really bizarre to me

 

[Dr Honda]

I guaranty that it wasn't an OEM ring. The white plastic ones will melt, and bubble up if something gets jammed in it. The OEM 140mm rings are fiberglass and hard rubber. If they become delaminated, then the black rubber just rips out.


Does it look like this?

 

[IDoSeaDoo]

It is an OEM ring: this ski has been in my family since it was purchased new. No work has ever been performed on the pump. This ski has been such a trooper, that I put a new pearl paint job on it, and am completely restoring EVERYTHING in it. (pic still coming)

 

[IDoSeaDoo]

Pictures

Well, it doesn't look nearly as bad as that melted ring, but it was still causing some baaaad cavitation

Does that tell any stories to anyone?

 

[Strizzo]

how much radial play is in the jet pump shaft? could the debris have thrown it out of balance enough that it cut into the ring?

 

[IDoSeaDoo]

Not sure because I couldn't move the impeller like that (it barely turns), the ring is making an almost perfect seal with the impeller. The inner-bullshitter in me says "just let it chew itself free, and you'll have the most closely matched wear ring out there". I know it's never that easy and once the paint job is done, I'll be tearing it apart and doing a full investigation. Never took one of these apart before though, are the early 90's 587 pumps the same as the mid-90's 720 and 787. I have a couple XP pumps that I THINK are in good order.

 

[Chester]

Do you ever ride in salt water? That's common on those old aluminum pumps when used in salt water.
What happens is the salt water creeps in between the housing and the wear ring. Then the aluminum corrodes over time and creates aluminum oxide (the white chalky stuff). As the aluminum oxide builds up, it expands and pushes the wear ring into the impeller. Show us a picture once the wear ring is removed.

Chester

 

[IDoSeaDoo]

ooooo.... that COULD very well be the issue... I did ride in salt water last summer. Is there any way to prevent this from happening in the future (as there are more trips already planned)? I'll def. let you guys know once I rip it apart. BTW, is it even worth repairing? Sounds like it's making a better fit now that it ever will. Should I just let it grind off the excess plastic and ride it?

 

[Bills86e]

If you want some better performance, a Scat-trac swirl slim-line 13/18 would be a great improvement over your stocker.
Any cuts/dings in the outer edges of the impeller will cut the oxygen modecules of the water and you will have an air bubble around the impeller, just spinning in the air, instead of moveing the water (cavitation). You'll be like driveing in neutral gear.LOL The center of the old impeller hubs were fat, so not much hydrodynamic flow.

Bills86e

 

[IDoSeaDoo]

i have a polished stainless Solas prop (not sure of pitch yet, it's still on the old pump) that came off the 91 SP. It's an OLD Solas, I think, but an improvement over the stocker. That one COMPLETELY ate the wear ring though, so I'll need to check and see if it's chewed up. How many cuts/dings are too many?

 

[IDoSeaDoo]

Chester, do you think installing a sacrificial anode to the pump body would help prevent this in the future?

 

[SabrToothSqrl]

http://en.wikipedia.org/wiki/Cavitation

A worn out wear ring does not cause this.

It may lead to additional cavitation, however poor pump performance does not mean 'cavitation'.

Poor pump performance means just that. Poor pump performance.

Cavitation is the creation and implosion of air bubbles in water, exclusively.

 

[Dr Honda]

Chester, do you think installing a sacrificial anode to the pump body would help prevent this in the future?

It will help, but the issue is after you get out of the water. The salt water is trapped, and it's not really an electrolysis issue. It's just corrosion.


Yes... you are right. It's an OEM ring. Chester is probably right with his diagnosis. BUT... it could also be that the rubber is getting ready to pull away from the fiberglass core, and you cough it before it cut though.

At this point, I wouldn't worry about it, and just do a pump service. (bearings, seals, and a ring)

FYI... I sell a set of inexpensive pump tools on my web site.

 

[SabrToothSqrl]

I have your tools...
and they worked.

the newer pumps for the 951s are plastic, and I assume don't have that issue. I do not know if they make plastic ones for your ski.

I like the plastic pump, it feels a lot lighter and changing the wear ring is a lot easier.

 

[IDoSeaDoo]

Doc, I have an impeller tool and a vice, what more do I need as far as tools go? What am I looking for in there in terms of wear? (this is my first pump job )