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Who's got the DL on replacing your idler & tensioner pulleys?
Another one of my little Covid car projects but not finding any good guides on this. The posts ive seen have inconclusive torque values, reference one idler being for the top and the other for the bottom (but dont say which), and talk about the tensioner pulley being a pain in the *** to get off.
You guys know im big on specificity. Any tips appreciated.
My car has an m96, I imagine the m97 to be similar.
The idler pullies are the same, but the spacer/standoff is different as the bolt sizes are different top and bottom. Top is a long m10 bolt that holds in the alternator. The lower bolt is an M8. Spec is 48lb ft for M10 and 17lb ft for M8. Tensioner, i'd do about 35 or so lb ft. with the red loctite its going nowhere.
The tensioner pulley is massive *** pain and terrible design. You will need to counterhold the bolt behind the pulley with a 15mm wrench. The outer nut is a 24mm and is red loctited, so getting it off is a proper bitch. Once off, there is a little spacer behind that you will need. It appears that the tensioner pulley is the same as the idlers as well (it was in my case).
My pullies were steel, so I just replaced the bearing and saved myself about $180, but I don't think thats happening with the plastic pullies.
Good timing on your post, Bruce. I've been hearing a short chirp on start up and occasionally on shutdown on my '08 C4S. Last week when I changed the water pump, I checked all the other belt driven components for issues but everything looked, spun and felt fine. The chirp is annoying so I went by my favorite independent shop this morning to ask the shop owner's opinion. I started it up several times while he inspected and listened. After a few minutes he strongly suspected a belt driven component. Now get this; he then dumped about a cup of water onto the bearings for all the components and that made it stop chirping. Thus he concluded that despite my careful inspection last weekend, one of the bearings is going out on an idler or tension pulley. There is also a chance its the alternator, a/c compressor or power steering pump so I'll check them more thoroughly before I start replacing the pulleys.
When I got back home I ordered the serpentine belt kit (Contitech ADK0029P) from Rock Auto. Interestingly, Pelican wants $473.50 for this kit compared to Rock Auto's price of $300.99. That's a no brainer.
Are these the only 3 pulleys needed for this? Looks like all 3 are ~$200 from pelican
. Sonnen Porsche usually has online prices that are the same or lower than Suncoast/Pelican, plus no shipping charges. I just swing by and pick them up. I guess the pelican parts must be OE.
Ok this was a simple project. 1hr, no gotchas. All three pulleys come with the dust covers and hardware bits. Because of that its clear which is the top and bottom deflection pulley. The tensioner comes with a new bolt, but the deflection pulleys do not. I reused all the the bolts and just cleaned them and put some loctite on. You need to remove the entire tensioner assembly to replace that bolt (because there is not enough room to back the bolt out of the tensioner arm) so I didnt think it was worth it.
I will do a proper right up when I get some time, but here are the basics:
1. Remove the box, belt and bungie the oil hose out of the way.
2. Use an E15mm for the top pulley and an E13 for the bottom
3. A 15mm wrench fits just fine behind the tensioner while you remove the 24mm but on the front side. You just need to fiddle with it a bit to get it positioned right. I used a breaker bar to break it loose and then a wratchet to get the rest of the way. It takes a bunch of turns to get off. Be sure to go slow at the end so all the washers dont fall out.
4. You cant back that bolt off the tensioner arm without removing the whole assembly. So I just cleaned it up and refused it.
5. New kit. Easy to tell which is the top and bottom deflection pulley.
Bottom pulley has the smaller ~E13 and dust cover Top pulley has the larger E15 and dust cover
6. Of course clean the engine with those bits out of the way.
7. All back together. I used the torques referenced above ^^
- 35 for the tensioner
- 17 for the bottom pulley
- 45 for the top pulley