Charley B

The only thing I can think of is the little belt guide roller that sits below the crank at about the 8PM position to the harmonic balancer. This is sitting at the 5PM position. It rolls smoothly and doesn't seem to touch anything.

Could that assembly have been installed backwards!!!! If it was, can I just leave it this way? I don't think it ever touches the belt when installed properly anyway.

P.S. I disconnected the sending unit to get a better picture.

SeanR

Depending on the year, there are either zero, one or two rollers. You've got a two roller car and a slight mess.

Charley B

Sorry. '88 S4. So it's a two roller assembly and belongs there?

SeanR

Yep, chances are they are sized or so full of dirt they wont spin. Just clean them up real good and they should be ok.

Charley B

Thanks Sean.

Hilton

Buy two 6201RS bearings (its a standard size and they're cheap).

When you remove the arm which the rollers are on (two small circlips), remove the rollers (two slightly bigger circlips and if stuck hard, a small puller). Then press the bearings out with a socket in a vise and replace them, after inspecting the roller surface for wear (driver's side will likely have none - so swap their sides).

the flyin' scotsman

The rollers hold the tbelt to the crank........sometimes.

Much debate sometime ago re effectiveness...........I took mine off and left them in the parts bin when I converted to the Porkesioner..........years and 1000s kms ago

btw........you need a OPG

GregBBRD

Porsche put them in there because they needed to add more weight and make the engine more complex?

James Bailey

You can get replacement bearings for little money.....originally it was a plastic slide like 911s use then one roller then two....But like Greg said it was just some engineer building job security and adding weight and complexity

Leon Speed

Since when does the roller sit on the left side of the crank? Ok I see two rollers, one on each side?

Vilhuer

Two on some MY S4's. Early S4 used single roller. Second version used two and final version one larger roller again. Changes were done in middle of MY in '87 and '90 MY starting fron certain engine numbers. Plastic cover behind roller was also changed at same time.

GlenL

We can't just sit there looking pretty.

dprantl

Those idlers are there because they are a bandaid for the silly characteristics of the stock tensioner. The belt can flap so much with it in certain circumstances (while it is properly adjusted to the factory tension setting) that the engineers were probably crapping their pants trying to figure out a way to fix it without completely redesigning the system. That is the only explanation I can envision, because I cannot fathom a smart engineer inserting a smooth idler pulley where the TOOTHED portions of the belt can contact it.

You will not find such a tensioner system in any car designed in the last 15 years. The design is adequate at best.

Dan
'91 928GT S/C 475hp/460lb.ft

Whitesands

+1