Other XC90 Problem: Smell of burning rubber and grinding noise

[Dave18050]

2011 XC90 D5 AWD. A couple of weeks ago I had a smell of burning rubber and a grinding noise coming from the vicinity of the auxiliary belt after a motorway run. The next morning the car would not start and when jumped alternator not charging and systems shutting down inc... ABS, airbags, no window power and stuck in what I think was 3rd gear (auto). everything pointed to Alternator.

Swapped out the alternator and new auxiliary belt. Problem solved, car ran fine . Did 1000 mile round trip in 2 days and all was good. good for another couple of weeks.

However, the burning smell is back and there is quite a loud grinding noise when at low revs (cant notice at speed, possibly due to road noise). Alternator seems to be doing its job and is over 14 V when running.

Plan is to remover belt and recheck pulley's, steering pump wheel and aircon compressor. All of which I checked before replacing the alternator.

The alternator I bought was not the most expensive on the shelf and cost around £200, could it have failed? seems to be doing its job!

could it be the none Volvo belt?

Anyone had something similar or any ideas what it could be? Thanks.

[Harley Dave]

Alternator pulley clutch??

Cheers

Dave

[tonygreen1966]

I had a similar problem. For me it was the air con pump pulley clutch had seized and the belt got hot then melted the plastic pulleys (PAS and tensioner I think). While I was changing all this I also changed the alternator pulley, which I'd read on here has a clutch that can fail and snap the belt. Did the new alternator come with a new pulley? There is a test you can do on the alternator pulley to check it- but my new pulley failed this but 4 years on and no problem. Someone will come along on this forum and explain the test- if not google it. Definitely appears you have a problem though. Did you check all the other pulleys for free running while you had belt off? Hope you changed the tensioner- belt failures often caused by failing tensioner and broken belts can get in the timing belt area and cause expensive damage. Switch the air con off and on and see if this affects grinding noise- air con pump has a clutch that only engages and drives air con pump when air con is engaged- maybe you have a dodgy air con pump clutch. Best of luck. Keep us all updated.

[Tannaton]

^^^^^ That.... check the A/C compressor pulley....

[Dave18050]

Originally Posted by Tannaton

^^^^^ That.... check the A/C compressor pulley....

Thanks. I am happy what to check on normal pullys, tensioner and alternator clutch pully, but is there any special check for A/C Compressor? Or is it just spins nice and free and has no play etc....?

[Tannaton]

Originally Posted by Dave18050

Thanks. I am happy what to check on normal pullys, tensioner and alternator clutch pully, but is there any special check for A/C Compressor? Or is it just spins nice and free and has no play etc....?

I'd pop the belt off and check it spins freely and smoothly with no play. It is possible to buy the bearing and replace it, though I did one recently where the bearing had siezed and spun on the shaft, ruining the compressor... that must have made a hell of a noise when it let go.

[Dave18050]

Update. Car will not start battery full. Got he Aux belt off and the car started. Tested all pulleys, free and no play. Steering pump free and no play. Did alternator clutch test and all good. Reached down to spin a/c compressor and as most of you expected, it is seized solid, would not spin at all!!!

So now I know the issue, it looks relatively simple to replace. However, there is the de-gas issue. Can it be done at home or will it need a professional? The manual does not describe the process.

Thanks again for advice and support.