2002 GTX 155 pump, Bad design or something else?

[68ragtop]

GTX 155 pump leak, Bad design or something else?

A little background first.

Last fall I bought a 2002 GTX 4-tec that was not running. When I got it, The pump bearing had seized & pretty much destroyed all the internal pump parts. It had 60 hours on it & very clean machine otherwise.

I rebuilt the pump & a few other things. It's been running pretty good but seems to me that it has a little bit more drive line rattle than I would expect for such a smooth running engine. So, this morning I decided to pull the pump to inspect everything for piece of mind. What I found was water in the pump bearing cavity! Not too happy about that to say the least. No damage yet as it only has 5 hours on it since the rebuild. Funny thing is, I bought a new cone for this pump & converted the original to pressure test it. I found no leaks at the time & none right now! What I did notice when assembling the pump is it had/has what I would consider a lot of radial play. What I believe is happening is the impeller shaft has a little too much movement & is letting water sneak in around the impeller shaft seal.

As you know, the bad news is this is non adjustable & the lateral/ radial play is pre-determined by the angle/shaft bearing. So what gives? My 2008 RXP has the same setup & has nowhere near this much play & zero leaks.

The only part I reused in this pump is the impeller & the housing. Everything else in the parts diagram is brand new BRP parts. ($300 worth in fact )

So did I get a bad bearing? I could possibly separate the races & machine one down to tighten it up, but thought I would get others opinions before I do anything at all.

seeing this had a failure at only 60 hours I have to believe this was the culprit the first time around as well.


68RT

 

[68ragtop]

tested it again.

No question the water has to be coming in from the impeller axle seal (part #23)
I pressurized it again to 5lbs & let it sit. Zero loss of pressure after 40 minutes. This is the same result I had when I rebuilt & tested the pump prior to installing it. BUT, this time I decided to wiggle the impeller back & forth to expose its radial movement. Specs show up to .75mm is acceptable & I am measuring slightly more than that. While wiggling it back & forth under pressure it will loose .5 lbs within 30-40 "wiggles" of the shaft. I also tested it under vacuum & the loss is much less severe.

So now what, try another bearing? take it apart & have the bearings inner races machined down to tighten it up? Really not adjustable in any other way.

Hhhmmmmmm.

 

[red2blue]

plastic pumps warp. toss it in the trash and get an aluminum one from a '05+ rxt.

 

[68ragtop]

plastic pumps warp. toss it in the trash and get an aluminum one from a '05+ rxt.

Your not saying plastic is causing the leak, are you?

 

[Coastiejoe]

Plastic pumps fail more often then the aluminum pumps. They can get out of shape and allow for issues.

 

[68ragtop]

While I completely agree with that, I don't see where that could have anything to do with the problem I have with this pump. On this one it is solid alloy right to the outer edge near the mounting ears. any flex near the outside edge it might have, really shouldn't effect the radial play the bearing has.

Its funny because when I first put the pump together, the bearing seemed sloppy, but I figured its just how it is. When I went through the pump on my RXPX that bearing was much tighter. Maybe I just got a bum bearing. If the thing wasn't $65 I would just order another one & see how tight it is.

I'll see if I can get some better pictures of whats causing the leak.