Took apart exhaust valve for cleaning purposes. After cleaning and reassembly, one of the bolt on top twisted off. I know this is a common occurrence and that most guys don't take them apart unless a bellow is ripped or torn, but this is pretty much the only time they've ever been apart and the break is NOT a fresh break.

Half of the stud where it broke is black -- the other half is bright grey aluminum in color. This tells me that this must have been cracked for a period of time for the aluminum to tarnish black and the final reinstallion finished her off. Buddy of mine says I must have a horseshoe up my ass because judging from how much the stud was cracked, it surely would have broke while driving and grenaded a cylinder, or worse.

The dilemma now is.....I have to replace one for certain because it is broken and unuseable. The other two appear to be in good condition, but I am nervous about running them. The one that broke, did not break from "wrenching" on it. The wrench just finished off what inevitable would have happened if nature was allowed to take its course.

Do I trust the other 2, and replace the 1, or....replace them them all and sleep well at night?

On another note,

I have removed my water pump and think that I am wasting my time. The water pump seems good and tight - bearings move freely without any rough spots and no indication of coolant leaking from sipe hole either. Sled has 4100 miles on it, but I think this rebuild may be immature. It just doesn't seem to me like it needs it? Pump feels very solid in comparison to the other 2 I've seen/worked on in the past. Main reason I'm rebuilding it is because of a catastrophic failure I had on our 98' XCR 700 at around 5000 miles. This pump grenaded so bad there wasn't a useable piece in it. Had to buy a used one and it started leaking in the middle of the season throught he sipe hole.


Comments??

Got a picture of the broken valve?
You talking about the stud on the end that holds the bellows?
Just do the broken one, IMHO.
On the water pump, why would you not replace the cheap bearings and seals if you have it out? They may go forever and they may not. At the very least, i would do the water seals, and pop the bearing seals out and re-grease them.
Good Luck

Yes...I can provide a picture of the broken valve a little later. Just seems a little scary since I don't think this broke due to overtightening. The break looks old. Wrench just finished it off – and it sure didn’t take much to do it either!

As for the water pump, I have ALL of the parts to do a complete rebuild.....including the bearings. I was just expecting the pump to give me some indication of wear.....it feels perfect. I'd hate to find out the hard way..... These water pumps are really starting to get on my nerves.

Bulletproof? …..hardly.

Hey Six. I broke two valves like that. I took them to a machine shop , they machined what was left of the stud off then drilled and tapped for a new "good " stud to be put in. That was the end of my trouble and worry over those things.

Hey TG,

What did that cost ya to have em' machined? Right now, I'm lookin at $75 a piece x 3. A year or two ago it was $90 X 3 for updated carb slides. Fug...this preventative maintenance stuff ain't cheap!

Now I've got the suspension out and my front torque arm is cracked in two places....again. There is supposedly a change up according to Polaris, but I have no idea if the changeup is any better than the original it replaces? I've already welded patched her up once before. Have you ever replace the front torque arm?

Been there did that on both cases. Ive welded up two torque arms and both times they cracked again. Dont seem to matter how carefull you are or what you weld it with. I ran an xc for quite awhile with it cracked assuming its cracked on the far side between the gussets. Probably stay that way for a long time.


Had the same deal as you with the pv. I bought a new one and left the other two. I did consider top guns idea by simply machining the top square and tapping a new set of threads. Its aluminum so it shouldnt cost that much and you could probably do it yourself.

You could have a machine shop copy and weld up a chrome moly torque arm. Rudulphs Indys used to sell the Chrome Moly arms.


Don

You can grind the piece flat to the shoulder where the threads stop.

Get a tap and drill bit for the existing size stud that was sticking out. Have to stay the same so the little bellow holding do dad will thread on.

Take a bolt of the same dia, and pitch, cut it and make a stud.

Drill your hole 3/8 down into the valve and tap it. Bottom tap works better then a starting tap, just go slow.

Just make sure your stud sticks out the same length as a stock one, make your stud longer to go into the valve you tapped.

Cost, drill bit, tap, bolt.


Drill a 1/8 lead hole first, less likelly to walk.

Yup, the above sounds great and honestly I wouldn't be afraid to try it. I had a buddy do it for me but in all reality it's quite simple. But when you insert the stud into the valve use red loctite or stronger. Also, buy yourself a mini butane lighter fired torch, Canadian tire slells them. If you loctite your caps you can heat them with that mini torch which helps spin them off. Great little torch.