nzskater

Anyone here done this before with the engine in?

Edit: Resolved - had the local OPC replace the rollers, which didn’t resolve the issue. As a last resort they replaced the new drive belt with another brand of drive belt, which has resolved it. Somewhat frustrating but at least my car has fresh rollers and the issue has gone. Win?...

Had my drive belt replaced, now getting a slight dry chirp from one of the rollers. Tried a little WD40 on the bearings of the three rollers but didn’t make a difference - guessing it’s one of them as a slight mist of water on the smooth side of the belt makes the noise disappear for 30 seconds.

Keen to do the job myself but can’t figure out how to access the pulleys (assume I need 8’s and a 5 below) in the limited space available or how the tensioner roller comes off (or whether I need to replace the whole tensioner?). Even with the Y pipe and air filter housing etc removed there’s not much room.

Can find a few posts here and on 6speed on Carrera or 996’s, but nothing for our cars. Looking for guidance before I get it done by an OPC.

lliejk

I did the tensioner roller out of the car, but while you have to remove some stuff, I think they are accessible while the engine is in. I only replaced the roller, not the tensioner itself nor any idler rollers. I bought the roller from Pelican (996-115-016-72-M219) for $95.

Since it was out of the car I cannot be sure you can do it while the engine is in. I do know getting to the nut behind the roller will be the challenge while the engine is in.

Ed

TT.BRN

Unless the rollers are cracked,I say just change the bearings, you’ll save a good chunk ...

nzskater

Thanks Ed, suspect I’ll be buying a few different tools to try and access it. If I do manage to get it out I also have no idea how I’d torque it to spec once the new one is in!

Was under the impression that there is not an easily available option for a bearing swap, any info on someone doing this? Rollers only $80-$100 each so not a major.

TT.BRN

New bearings are like 2-3$ each .... press them out and get new ones from any hardware store ...just dont get the Chinese ones ...

nzskater

Understand how it works, just never seen anything to suggest they can be pressed out in this case. Has anyone else actually done it?

Edit:// Drove the car today, first time in a week - noise all but gone. Guess the belt has stretched a tiny bit. Will procrastinate on replacement until it comes back

911.Forever

good to know, thx nz

nzskater

Aaaaaand it came back. Went away for Xmas/NY and driving for the first time yesterday heard a slightly lesser chirp from the engine bay. Damn it.

Still unsure how to do the job - info on replacing them is very limited, with everyone doing it with the engine out of the car... there’s got to be an easier way?

hankcah

Are you still having any squealing or chirping? If so, check out - https://rennlist.com/forums/997-foru...t-997-2-a.html and pelican parts has a few DIYs which may have it. Else, post a question on their forum and you may receive a better tip or two.

Side Note: you shouldn't lube anything near the pulleys or belt. And out of any lube, WD-40 is the worst thing you can use. I learned this the hard way.

nzskater

Yes, still chirping although is quieter after sitting for a month. Thanks for that info. Unfortunately the guides and DIYs are all for NA cars or 996’s. The layout of ours is quite different, and the pulleys sit lower on the engine (or at least the third/right one does).

WD40 was used to troubleshoot. The tiniest amount direct to the bearing area to see if the noise changed at all. It didn’t. Agree on avoiding lubrication of the pulley or belt itself!

lliejk

Do you have a mechanic's stethoscope and did you use it to isolate which roller(s) are causing the noise?

It's not the alternator, PS Pump or water pump making the noise?

Did you check the edges of the belt to see if one side is sharper than the other? Do you have the old belt still around?

Ed

nzskater

Thanks Ed. All great pointers.

Have not got a stethoscope - intended on picking one up today. 90% sure it’s the lower right roller, and that it isn’t one of the accessories due to the noise significantly changing when I slightly mist the smooth side of the belt with water. That said, not exactly a precise test so could be anything. Will get hold of a stethoscope and see if I can isolate it, and also check the new belt. Unfortunately the old one would have been discarded by the OPC that did the service.

ble2011

If you think it’s just the belt, back in the old days, we had belt lube. It really wasn’t a lube at all but some kind of conditioner that stop the belts from squeaking. It turned sticky after spraying. A little goes a long way. Maybe worth a try before tearing into it.

nzskater

Update on this - tried a mechanics stethoscope, but the lack of space and no way to actually see anything made it pretty much impossible to isolate the culprit. Lots of contact and noise as it touched on parts but nothing that indicated where the chirp was coming from.

Took a more rudimentary approach and used some garden hose, as it allowed for more general directional assessment - now starting to think it’s the AC compressor, as there is a very slight variation to the sound when AC is on. Not the best news as the compressor is significantly more than the roller...

Taking it in to Porsche Tuesday as they replaced the belt and can give a second opinion. Will then make a call on what to do. What a ball ache.

Thanks for the tip on belt spray. Tried a tiny bit, didn’t make it any better.

lliejk

When the A/C compressor kicks on it will change the dynamics of the accessory belt tension, so while it may be related to the A/C, it may not be the compressor causing the noise. The stress of running the compressor may be causing the noisy component to see more or less stress depending on where the noisy component is in the loop.

Keep that in mind when you hear whatever the P-Car guys have to say. Compressors are way more expensive than rollers & a tensioner and the compressor sits right on top of two of them.

Ed