Noise in engine bay from alternator cover area

[mrgobby]

Bit of a punt asking about noises I know but it started this week and apparently getting worse (i dont drive it much) it was heard on tickover a rumbly vibey noise that goes away on raising engine speed a bit, seems to emanate from belt cover area by alternator, 118k 57 plate manual, any suggestions on likely causes, don't think steering pump as seems to work okay no special squeals, could be alternator bearings I thought but figured the rumble would get worse not go away but a possible, surely not crank related! Anyway other options are Johnsons Volvo in Oxford for a service due and ask for a diagnosis or any suggestions on local specialists in West Oxfordshire? Gods I hate it when cars play up! Thanks Mark

[Ducklakeview]

Originally Posted by mrgobby

Bit of a punt asking about noises I know but it started this week and apparently getting worse (i dont drive it much) it was heard on tickover a rumbly vibey noise that goes away on raising engine speed a bit, seems to emanate from belt cover area by alternator, 118k 57 plate manual, any suggestions on likely causes, don't think steering pump as seems to work okay no special squeals, could be alternator bearings I thought but figured the rumble would get worse not go away but a possible, surely not crank related! Anyway other options are Johnsons Volvo in Oxford for a service due and ask for a diagnosis or any suggestions on local specialists in West Oxfordshire? Gods I hate it when cars play up! Thanks Mark

Probably the alternator clutch, easy DIY swap, but can be awkward to get off.

Mike

[Tannaton]

Another prime candidate is the bearing on the AC clutch pulley. Does the note change when the AC is operating? If it is this bearing it can be changed with the AC compressor in situ without draining and refilling the AC system (the main dealer will simply replace the compressor though).

To best diagnose where the noise is coming from you need to go on the internet and get some of these:

http://www.ebay.co.uk/itm/Automotive...cAAOSwvzRX0G5h

A long screwdriver can also be used to good effect as a listening stick.

[gmonag]

Take care when working near the rotating belts and pulleys!

[mrgobby]

Thanks for replies, misses took it to local specialist who suggests the belt tensioner and so I will report back when done if it's fixed, I've not time at mo to delve into it myself

[TONY GRYSIUK]

Have 2005 S60 auto 69k miles. Had deep rumble from alternator belt area at beginning of year. At same time had a leak on power steering pump so this was replaced along with new belt, noise went away for a time. Has slowly got worse to the point that it vibrates in the cabin on tickover. When revs increase beyond tickover noise abates. Took it into local garage said it sounded like a 'dual mass flywheel' or something like that then realised it was an auto. He checked the bottom pulley and then thought it could be the belt tensioner as when load put on engine noise went away. New tensioner fitted today, still the same. Mechanic said he had spoken to an auto specialist who said certain Volvo autos have this 'dualmass flywheel'. It is our only car so don't want anything to go bang. Any ideas where to go next apart from another garage?

[oragex]

That mechanic deserves some kind of award.

Is it a diesel or petrol engine?

You have low miles so its a bit early for this, but the pulley on the air conditioning compressor may start to rumble - only the bearing needs replaced without removing the compressor. Is the air cond cold enough?

The alternator pulley also can go bad. If the whole engine is vibrating a mount may be bad.

But all these can be tested by hand before replacing anything. Just have a (good) mechanic remove the belt and spin the pulleys by hand.

[TONY GRYSIUK]

It is a D5 diesel. Have just been to another garage and mechanic said it is the alternator pulley as the belt can be seen moving from side to side. He also said that this would cause a noise on full lock. Checked this any hey presto it did. The air con is very cold so hopefully it is the alternator pulley that is a little tired. Getting it fixed week after next. Thanks for pointing me in the right direction.

[cassell]

Originally Posted by TONY GRYSIUK

It is a D5 diesel. Have just been to another garage and mechanic said it is the alternator pulley as the belt can be seen moving from side to side. He also said that this would cause a noise on full lock. Checked this any hey presto it did. The air con is very cold so hopefully it is the alternator pulley that is a little tired. Getting it fixed week after next. Thanks for pointing me in the right direction.

I don't think I would leave it until the week after next! If that alternator clutch pulley seizes and/or comes adrift it may cause the auxilliary belt to take out the cam belt and you'll be looking at a new engine!

[cheshired5]

Originally Posted by TONY GRYSIUK

It is a D5 diesel. Have just been to another garage and mechanic said it is the alternator pulley as the belt can be seen moving from side to side. He also said that this would cause a noise on full lock. Checked this any hey presto it did. The air con is very cold so hopefully it is the alternator pulley that is a little tired. Getting it fixed week after next. Thanks for pointing me in the right direction.

My video for testing and replacement can be found here.