Diesel Compressor pulley

T16 · 13th December 2014, 13:09

Ive recently had a rattle at cold starts, and it sounds like a knackered bearing.

The crank pulley was done in the last 40k, and it shows no signs of witness marks or noises.

The noise seemed to be coming from the front, and I replaced the A/C tensioner, which was noisey, but the rattle is still there.

How easy is it to replace the A/C clutch and pulley? I see there is a single bolt on the end, does that mean the whole assembly comes off easy, or is there more to it than that?

Obviously i need to source a 2nd hand pulley and clutch first though, but any advice welcome..

Mike Noc · 13th December 2014, 13:43

I've had a water pump fail and sounds very similar to the crank pulley. Easy enough to check for play once the serpentine belt is off.

Try running with the aircon belt disconnected before changing anything on the compressor.

This was the sound of my water pump:

https://www.youtube.com/watch?v=cuHeZmkcyrs

Given that the crank pulley has done just over 360,000 miles I was close to ordering a new one before I had it all apart.

T16 · 13th December 2014, 14:06

Well I took off the tension on the belt, and as best I could spun the water pump pulley, and there was no play in it, and it was smooth enough.

Annoyingly the nut on the center of the tensioner starts to turn before I can get the tension off enough to get the belt totally clear, but I think it was enough to make sure that the pulley turned without any notching, and it was rock solid in place... no play etc, so I guess thats good news.

Im thinking it has to be A/C as the rattle gets worse when I put the A/C on, the the noise is definitely from the front rather than the crank pulley area!

Also crank pulley has no witness marks or anything... So I guess if I can get a cheap 2nd hand A/C pulley, I can see whats what.

This is what I need to know I think, how hard are they to change?!

SD1too · 13th December 2014, 14:32

Quote:

Originally Posted by T16

... the rattle gets worse when I put the A/C on ...

Ross, from what I've read on this forum those are classic symptoms of a delaminating crankshaft pulley. It's the extra load which produces the noise. I've also read recommendations to fit a certain brand of pulley because others don't last very long. Could that be the case with yours?

To find out for sure, instead of guessing that the noise "has to be A/C", you should follow Mike's suggestion:

Quote:

Originally Posted by Mike Noc

Try running with the aircon belt disconnected before changing anything on the compressor.

Simon

T16 · 13th December 2014, 14:41

Its a Corteco original pulley...

If I slacken off the A/C tensioner what should I do to see if the bearing is gone in the A/C Compressor pulley?

Engage the clutch and turn? Or leave disengaged and turn?

13th December 2014, 13:09	#1
T16 I really should get out more....... ZT CDTi 135, ZT260SE Join Date: Feb 2011 Location: Dundee Posts: 2,877 Thanks: 10 Thanked 331 Times in 213 Posts	Diesel Compressor pulley Ive recently had a rattle at cold starts, and it sounds like a knackered bearing. The crank pulley was done in the last 40k, and it shows no signs of witness marks or noises. The noise seemed to be coming from the front, and I replaced the A/C tensioner, which was noisey, but the rattle is still there. How easy is it to replace the A/C clutch and pulley? I see there is a single bolt on the end, does that mean the whole assembly comes off easy, or is there more to it than that? Obviously i need to source a 2nd hand pulley and clutch first though, but any advice welcome..

13th December 2014, 13:43	#2
Mike Noc This is my second home Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4. Join Date: Jul 2009 Location: Hampshire Posts: 11,557 Thanks: 3,470 Thanked 3,119 Times in 2,247 Posts	I've had a water pump fail and sounds very similar to the crank pulley. Easy enough to check for play once the serpentine belt is off. Try running with the aircon belt disconnected before changing anything on the compressor. This was the sound of my water pump: https://www.youtube.com/watch?v=cuHeZmkcyrs Given that the crank pulley has done just over 360,000 miles I was close to ordering a new one before I had it all apart.

13th December 2014, 14:06	#3
T16 I really should get out more....... ZT CDTi 135, ZT260SE Join Date: Feb 2011 Location: Dundee Posts: 2,877 Thanks: 10 Thanked 331 Times in 213 Posts	Well I took off the tension on the belt, and as best I could spun the water pump pulley, and there was no play in it, and it was smooth enough. Annoyingly the nut on the center of the tensioner starts to turn before I can get the tension off enough to get the belt totally clear, but I think it was enough to make sure that the pulley turned without any notching, and it was rock solid in place... no play etc, so I guess thats good news. Im thinking it has to be A/C as the rattle gets worse when I put the A/C on, the the noise is definitely from the front rather than the crank pulley area! Also crank pulley has no witness marks or anything... So I guess if I can get a cheap 2nd hand A/C pulley, I can see whats what. This is what I need to know I think, how hard are they to change?!

13th December 2014, 14:41	#5
T16 I really should get out more....... ZT CDTi 135, ZT260SE Join Date: Feb 2011 Location: Dundee Posts: 2,877 Thanks: 10 Thanked 331 Times in 213 Posts	Its a Corteco original pulley... If I slacken off the A/C tensioner what should I do to see if the bearing is gone in the A/C Compressor pulley? Engage the clutch and turn? Or leave disengaged and turn?