98 XJR Supercharger Questions
 

Everyone,

After my shop heard some loud noises coming from the Supercharger, a front bearing repair kit was ordered. While waiting on the parts, the guys at the shop have taken off the Supercharger and called me over this afternoon to discuss the inside.

Below are pictures of the inside and have raised some questions from the mechanics about how to proceed. They are concerned about the Teflon coating on the inside (compressed air side) of the rotors.

My question to the board, would this only effect performance? Should we reject the front bearing kit coming in the mail and instead search for a re-manufactured supercharger?

I only have 83,000 miles and the car seems to have been well cared-for. Although I have only had the car about 5 months.

Any advice would be greatly appreciated.

Thank you in advance,
-David

David, I rebuild these and general opinion on the coating is some do, some don't (on refinish of the coating) if any impact on performance, it's negligible. I strip and polish.

Basically it's a blower, not a compressor, so sealing isn't important to performance....

The loud noises, was it induced coming off revs? at idle?

Looking at the wear, it's towards the rear needle roller bearings, I'd replace these as well as the snout bearings, then it's job done. Correct high temp grease is important in these.

One test your guys can do is turn the pulley by hand to and fro - clockwise/anticlockwise and see if there's play before the rotors move, this confirms if the coupler is worn. If so then the snout bearings and coupler is required. Pretty much a given.

Sean,

Thank you for the reply.

The noise was mostly at idle and could be heard the most while standing at the front of the car with the bonnet raised.

I was able to turn the rotors myself and they are tight (no play) in either direction. They are not free spinning however and once pressure is released they quickly stop.

By the rear needle, I am assuming you mean the rear of the rotors themselves, where the two rotors attach to the rear of the s/c housing. I don't think those parts were ordered because the parts house said the front wear out 2-3 times before the rear need replacing. But I'll have my mechanic check.

I'll also mention the high temp grease. Where exactly should that be applied or will they know that? I'll post more on the kit they ordered for $99.00US that supposedly has "everything needed"?

Thank you again.

-David

My xjr has a loud knocking noise coming from s/c

Time to replace your coupler...

My issue was the bearings and this kit from this eBay seller did the trick:

My model's Supercharger Bearing Kit: Eaton M112 Supercharger Snout Rebuild Repair Bearing Kit Complete | eBay

I can't say enough about the seller. He was fast in getting the package to the shop, and my mechanic was pleased with the contents.

As for the finish of the internal rollers, all I did was clean them to remove any debris and left the finish as is.

Hope that helps, David.