Sonic dB

When I purchased the 993 a little over a year ago, it had a set of rear tires that were almost bald, but they held air. I replaced them in January and the drivers side rear started having a slow leak, where it would need filling up about every week or so. I had America's tire inspect the tire, and they said it was OK but after they put it on, the slow leak continued. About 2 weeks ago, I had them put a new tire on that rim....but now the leak has started again.

Obviously there may be a problem or hole in the rim. It is a Solid Turbo Twist, 18" Rim...

Anyone have any ideas as to what to look for when I take the tire off the rim?
Also, are these things repairable, if its a small hole, such as via a weld...?

Thx.

stace

I have the identical problem on identical rims. with one difference my wheels are chromed (PO's choice not mine really). unmounting a tire quickly revealed that the chrome, while fine on the face of the wheel, was coming loose on the inside sealing surfaces of the rim. a few minutes with a wire brush mounted to a drill motor (on those sealing surfaces) has improved the problem but not totally solved it.

I would suggest very careful inspection of the wheel - maybe reveal a flaw or nick that can be polished out.

just my experience

c993k

There's a good possibility you have a hairline crack in the center portion of the wheel.
If you run over something, with these low profile tires it happens. Chris

Bull

Could be a hairline crack in the wheel, but that is usually a problem with Hollow Spoke wheels, like the wheel in the picture. With your solid spokes (which will crack, but likely not leak from the crack) I would suspect either the area of the rim where the bead of the tire seats, or a bad valve.

I just solved an identicle problem with a winter wheel for my wife's Benz. It leaked last year, and I had the shop remove the (new) tire, replace the valve stem and clean the surface where the tire seats to the rim. It continued to leak slightly, with air being added every two weeks (a few pounds). I personally cleaned the rim and wire brushed it this year, remounted the tire and there has been no leak for a month now.

Sonic dB

Hey, Thanks guys... I just checked the wheels to be sure, and they are hollow-spoke, not solid as I had assumed. Im going to have it checked out on Monday... thanks for the pic Chris and info everyone else.

geolab

happened to me once on my hollows, changed the valve, $7 from dealer.
the metallic valves do not come with metallic caps though, replaced with old cap

Garth S

Fill a squirt bottle with a shot of dish wash detergent and water - and go leak hunting. Generally, one will find the bubbles forming after a very short 'hunt'.

Caveman

It may be paint bubbling up a bit at the edge of the rim. Have you tried having the tyre taken off, the wheel cleaned up a bit and then the tyre refitted?

Cheers,

David

ggoodwin

Nosing around the wrong forum I know... :-)

Have had similar issue where the tyre would loose 10psi+ in a week - it was getting ridiculous.

Went to local tyre fitters, they found air leaking from joint between tyre and wheel at the rim. (as Caveman says)

The fix was to remove the tyre and sand/file corrosion/loose material/rusting paint etc from the inside of rim, then brush on extra tyre sealant as a precaution and re-fit the tyre.

GarryG

Sonic dB

All good suggestions... I dont have any facilities to check the tire/rim at home...so I am going to ask the guys at Ams Tire if they will check it for me, and if I can see it too...tomorrow... now I know what I need to look for, thanks.

lowblow

Man does this sound familiar. Same thing just happened to my hollow spokes. The tire only seemed to lose air while/ after I drove it.

Turned out to be a cracked rim. When I drove, the crack must have flexed/ widened and the leak would become more prevalent. I drove it with too little air and trashed the tire.

$350 for a good condition used wheel, $129 to have it stripped, re-painted and new tire mounted and balanced and now it's as good as new.

I now understand the load these tires endure with the rear weight bias of these cars and check my tire pressure every week.

Mike

Sonic dB

Yeah thats basically what is happening.

Can these rims be repaired / welded to fix small cracks such as the one in the photo? Seems like that would be cheaper than having to hunt down a single rim and get it refinished like the other 3... anyone know?

lowblow

Yes they can be fixed but I'm not sure if it's worth the risk. I don't think you would want to put the wheel under the stresses that it was originally designed for if it has been repaired.

I would also worry that this wheel, should you sell it or maybe even sell the car, could end up on the track. Couldn't live with myself if a blowout occured causing an accident. As my mechanic told me, "get it out of circulation and make a hose reel out of it".

However, should you want to try to repair it there is a company called Turbax. They re-finished my wheel and also make repairs. I was very impressed with the quality of their work, the timeliness to complete it and the pricing. I believe they are a national company with many offices.

Mike

chris walrod

Ideally, no -- practically, yes but depends on where and how large the repair area is. There are many good wheel repair shops around these days.

JasonAndreas

Most likely unrelated to your problem but there is warning from Porsche not to use commercially available screw-in metal valve stems with hollow spoke wheels because of their length. The Porsche stems are only 43mm!