One way clutch or pulley?

[pgill]

Or if you prefer you can buy the original part but not in a Volvo Box

The Land Rover LR2 has the same engine (I own a LR2 and a S80 both with the same 3.2)

$133 for LR005993

https://parts.landrovertampa.net/Land-R ... 141422.htm

[pgill]

This Video is more representative of my actual experience.

Solid pulley --> the tensioner can't control the movement

AOP (one way clutch only) --> significant improvement, about 90% of the movement eliminated

AOD (One way clutch and damper) --> even better, about 99% of the movement is eliminated


For my Audi the belt was moving like the solid pulley in the video and I replaced the AOP but it didn't solve the problem so then I replaced the Tensioner (which also has a built in damper) and the excessive movement went away. (it moves like the AOP in the video and it has always operated this way since new)

For my Volvo and LR2 the pulley failed after 100,000 miles so I replaced the expensive AOD with an inexpensive AOP.

Even with the Volvo AOD completely locked up the belt movement wasn't excessive.

My plan is to use the cheaper part and to change it out when the clutch mechanism no longer works.

With the new part I can grab the belt near the AC compressor and it moves easily in one direction and not at all in the other.

[toolpusher]

Talked to an independent Volvo shop - they told me they have never seen a one-way clutch / pulley gone bad (other than by a snapped belt that was tangled with the pulley) and suspect that the READ unit is the source of the rattling / grinding noise.
Argh, what a complicated topic this has become.

[pgill]

For my 2008 LR2 and my 2010 S80 I have seen a 100% failure rate for the clutch pulleys that I've replaced as part of preventative maintenance (3 failed out of 3 replaced, I still need to replace 1 more for the Alternator on the S80)

Note: the AOC on my Audi did not fail and the old part still worked fine at 50,000 miles

The idler pulley and the pulley for the tensioner can make noise as they get old. (and these do fail, I can post a link if you want to see it)

Also the PCV can fail and make weird noises.

The power steering reservoir has a screen filter that can get clogged and starve the pump which will make strange noises.

If your turn the wheels does the sound change?

[toolpusher]

Hi, I use the times currently to give it a try. Can anyone help me figuring out how to get the bracket out that holds the ac compressor and the tensioner pulley? I got 4 screws out but that thing is not moving. Arrow indicates orientation of car forwards. 07 xc90.

[pgill]

This picture I should help

I marked it with red sharpie to make sure that it was still align upon reassembly

You need to remove the bolts where the red sharpie marks are

The bolt head is about an inch to the left of the sharpie mark in the picture




Thanks

Paul

[toolpusher]

Thank you! I already have those two loose, so I guess it just needs a good hit to come loose.
On a YouTube video a guy said for the earlier models like this one, a special tool is needed to re-align the bracket with the engine and other pulleys?

[pgill]

Remove the belt tensioner

I see from your picture that you didn’t

I can’t remember if the tensioner is in th way for removing the bracket

But I did remove the tensioner first

Good luck

Paul

[toolpusher]

Perhaps it is helpful for some: There is a third screw on the front of the bracket. It is covered by a cable harness.

To get that out of the way you need to loosen two clamps and a zip tie.

[pgill]

Victory!!!!!!

I forgot about that third bolt

Next time I will take more pictures

Congrats

Take care

Paul