Weistec Billet Idler Pulleys Installed
 

Just installed these this afternoon. Totally straightforward, if you can turn a wrench you can install these. Took a bit longer because I had to remove the radiator fan to get clearance, and that thing is finicky as hell to take out (although it slid easily back in).

First of all, I had 3 bad OE idler pulleys. 2 were just loose with some play, and 1 was really bad and rattled (upper left ribbed one above the alternator). For reference, my car has 35k gentle miles on it. Belt looked fine, but those pulleys were going to go sooner rather than later. Probably good preventative maintenance for anyone with more than 5 years on their car to replace them. New belt and tensioner too.

There is a very tiny amount of play on my water pump pulley (and the face and center bolt has rust on it - odd). Not sure how bad it is, but will have to keep an eye on it. Could probably use new radiator hoses as well, and will change them out before winter.

The Weistec pulleys are solid. Installed all of them and torqued to the spec per WIS. Didn't have the torque spec for the tensioner pulley, as MB never envisioned it coming off I guess. I torqued it to 30nm, but if anyone has a definitive on this it would be appreciated. Also, for anyone doing this themselves, don't forget to keep the snap-ring side facing out, and put some blue Loctite on the threads as 3 pulleys are at 20nm and the other 3 are at 30nm - it's not much. The new pulleys do not spin freely (not even when in hand on a finger), but I attribute that to the new bearings being stiff.

One other thing I noticed. The power steering fluid had clearly puked at some point at least once, as there was a ton of residue collected on top of the reservoir and around the cap. Looked at the dipstick, and it was barely registering any fluid. Good thing I'm flushing and refilling with the Redline this week. Will report back here on that.

That's it, didn't see anything else out of the ordinary down there. Didn't start her up as I have a few other things to take care of tomorrow probably. Just wanted to say that these pulleys should be considered preventative maintenance. Half of My OE pulleys were bad, and I have no doubt that they were on the verge of failure.

Was thinking of installing these when I upgrade to a Weistec stage 6! Lol

Good to know. Is there any noticeable difference in weight compared to OEM? I'd imagine a bit of an increase?

I should probably do this with a new belt as well. I'm just over 126k km (~78k miles)

"Gentle" miles ;)

There are reports of even the Weistec pulley bearings failing, (especially on SC applications) - bearings may not be as heat resistant as previously thought, so prolly good to still keep an eye on them

My car is currently at the dealer because I'm looking at Valve Stem Seal issue (hopefully the warranty covers it) and while it's there, I checked my belt and it's on the verge of failing.

2 of my idler pulleys are bad. I will replace them with Weistec. Probably a good idea to replace the tensioner pulley while at it. I get the idle pulleys replaced for free because of the warranty. Is it worth to opt out from this particular coverage and go with Weistec pulleys or replace them with OEM for now?

I'd say they're about twice as heavy as the OEM plastic pulleys. Since they're just idlers and not driven, I would imagine that there's no impact on performance.


My belt/pulleys were not making any noise. I would have had no warning when they failed. They were all worn, but the 3 I described above were a real problem. I'd just do it, it's cheap maintenance.


Haha, yeah my car has been babied. ;)
That's interesting thanks. I think I'm probably good for at least as long as the plastic pulleys were in there. The thing about "keeping an eye on them" though, is that they may not give any visual or audible warning when they're going. You have to actually take them off and look at them, shake them, etc. Maybe every 2yrs I'll get the bearings replaced, or next time around upgrade the bearings once and for all.


I don't know if it's worth it to you or not. If you're getting them replaced free under warranty, I'd just do that. There's no performance benefit, and new OEM pulleys are pretty durable and perform just fine.

Answering my own question. All billet pulleys torque to 31nm with red Loctite per these Weistec instructions for Stage 3 supercharger.
http://weistec.com/media/productfile..._3_upgrade.pdf

So I guessed right on the tensioner pulley. But for the smaller idlers, WIS has them at 20nm, while Weistec thinks they should be 31nm. That kind of detail on the actual billet pulley instructions would have been helpful Weistec..... :rolleyes:

I think I'm good. Red Loctite sounds like overkill, right?

Last update. Before starting up, I flushed out my power steering fluid. I used Redline Power Steering Fluid for its higher temp properties, and it's also more viscous at higher sustained temps that I see on track which should provide some added protection. (https://mbworld.org/forums/c63-amg-w...rack-duty.html)

And I'll need it. First drain out of the reservoir, whatever was in there came out BLACK. I drained into an empty bottle, and light wouldn't even pass through it. No bueno. Fill with Redline, start up car, turn the wheel back and forth for a minute, shut off car and drain again. Still coming out black. Again. And again. And again. Last time it came out a bit murky, but was massively better than what was in there. Used up the entire liter of the Redline doing it, probably should have used the Pentosin for the flush, but whatever. This should last me awhile, but the PS fluid was clearly never changed. I can tell that the steering feels much lighter already, and no noises from the rack that I had before but didn't really notice.

Back to the idler pulleys. The car is much quieter now, it's pretty shocking. Can't put my finger on what noises exactly are gone, but it's running great. Success.

Nice work. I always like it when even some boring preventative maintenance can yield a tangible difference, even if it's a slightly quieter or smoother engine. That way you don't feel so bad....well that's how I think at least :o: