Which pulley is this?

[Mr. Detail]

I recently had a new alternator installed and the mechanic also installed a new serpentine belt.
Tonight when I had the hood open, I heard a small whining type sound and aimed my work lamp
down towards the serpentine belt area. The pulley I show in the attachment is slightly wobbling.
Do I need to replace this pulley or did the mechanic possibly tighten the belt too tight?
Not sure which part this would be.

[erikv11]

That's the drive belt idler pulley, 8627994 for an 02 V70.

The serp belt tension is determined by the spring in the serp tensioner so no issue with how tight the mechanic adjusted something. Not sure if a slight of wobble is unusual, haven't really looked there carefully. FYI you possibly could re-pack the bearing to address the whine, though that would only quiet it down not remove any wobble.

[Mr. Detail]

erikv11, is this fairly easy to change out with a new bolt?

[erikv11]

I changed this pulley on my 07 XC70 and I don't remember any unusual details so I will say it's not a bad job. Very similar to replacing the tensioner. I was doing other items at the same time but here's what you would need to do:

- Probably easiest to move the power steering and coolant reservoirs out of the way for this job.

- Remove serp belt. To do this you put a large torx tool (I think T60? Better search on that one) in a star-shaped recess above right of the center of the 6-lined circle above and left of the idler pulley in your picture, and rotate clockwise to release tension on the belt. Access is limited and this step is easiest with a special tool but you can do it with a generic socket and a long ratchet. With the tension off just slip the belt off the idler pulley; leave it on the other pulleys if you can. There are likely good videos out there for this step.

- Unscrew the single bolt in the center of the idler pulley, access will be limited again but not incredibly, then swap in the new one.

- Reinstall the serp belt. Nothing fancy, just rotate the tensioner clockwise again, fit the belt, release the tension. Done.

Fitting the belt can be clumsy. You can lock the tensioner to the right or have someone help you by holding it clockwise until you get the belt in place.

Many of these steps are described at the start of this thread; though it is long-winded and packed with minutiae and suited to other procedures it is also thorough: viewtopic.php?f=10&t=83521

[Mr. Detail]

erikv11, would this help at all?

https://www.fcpeuro.com/products/serpen ... 75#reviews

[erikv11]

That would help, but you would also need to buy a T60 torx socket to put onto it, in 3/8 drive size. About the same coast overall but more versatile than ...

For an 02 FCP sells a ready-to-go serp tensioner tool, it's this slightly more expensive one: https://www.fcpeuro.com/products/volvo- ... 0-cta-8760

People have come up with several clever (cheap $) ways to unload the serp tensioner but from what I read those dedicated tools also work well.

[abscate]

If you don’t have the big 3/4 square on the 1992-1998 P80 you can remove the tensioner, slip the belt on, the install the tensioner and position it with a stick or broom handle , being careful with the belt

The 1999 and 2000 use a 14mm hex so you can tension with more conventional tools and leverage

I’ve had trouble with two Conti belts being too tight in late 2021 now. Doing a Volvo one today

[erikv11]

If you don’t have the big 3/4 square on the 1992-1998 P80 you can remove the tensioner, slip the belt on, the install the tensioner and position it with a stick or broom handle , being careful with the belt

The 1999 and 2000 use a 14mm hex so you can tension with more conventional tools and leverage

I’ve had trouble with two Conti belts being too tight in late 2021 now. Doing a Volvo one today

OP has a P2. An 02.

[Mr. Detail]

Thanx guys! I believe this pulley I have asked about is called the "idler pulley", right?

[erikv11]

Yep! E.g. "Volvo Drive Belt Idler Pulley - Genuine Volvo 8627994"

https://www.fcpeuro.com/products/volvo- ... ey-8627994