Bearing noise-M10 1.8 lump

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Roundymooney
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Tue Apr 11, 2006 10:03 pm

Hey gurus...

Car is approaching completion, but have one brief question.

Temperature is rock steady_(although takes longer to get there since I changed my manky coolant!), but I have "bearing" noise from the front of the engine (M10) which is only slight, and seems to ease off as the car heats up. Are the vicous couplings known for bearing noise (a regular cyclic squeak which varies with RPM), or am I looking at alternator bearings, or the bottom pulley (water pump here?)? I have neither PAS nor aircon to contend with so ,as I see it, it's one of these three possibilities. I need to change the fan belt, so I assume running the engine without for a brief period will do no harm in order to ensure it's not coming from the top end-which I am almost certain it isn't...?

TIA...

R
DanThe
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Tue Apr 11, 2006 10:09 pm

Water-pump tends to be the favorite for this, you should be able to tell just spinning it by hand, or there may be some play in the bearings
HTH
DanThe
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Tue Apr 11, 2006 10:12 pm

Missread you post :mad:
If its a "squeak" its more than likely to be the belt :wink:
gcorky
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Tue Apr 11, 2006 10:13 pm

well all of your suggestions are possible ,try removing viscous breifly,then remove belt and check waterpump as you will be able to feel be bearing play or roughness.removing belt would be ok breifly FOR THE SAKE OF THIS DIAGNOSIS THOUGH,DONT DRIVE WITH IT OFF :mad:
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Roundymooney
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Tue Apr 11, 2006 10:13 pm

It does indeed, Dan. Thanks. Other experiences are always nice when facing into the unknown 8) [/quote]
gcorky
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Tue Apr 11, 2006 10:15 pm

and seems to ease off as the car heats up.
well could be indicative of viscous as it locks as temp rises.
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Roundymooney
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Tue Apr 11, 2006 10:39 pm

DanThe wrote:Missread you post :mad:
If its a "squeak" its more than likely to be the belt :wink:
No, not that kind of squeak if that makes any sense :)

I do hope it's not that water pump... a pricey commodity, whereas an alternator bearing is easily sorted... I think the car got a new pump in the last few years, I must go through the receipts that came with...

Thanks for the input anyway mate.
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Roundymooney
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Tue Apr 11, 2006 10:45 pm

gcorky wrote:
and seems to ease off as the car heats up.
well could be indicative of viscous as it locks as temp rises.
I thought that initially, too. Said fault is inaudible with the bonnet closed, it's that slight. I don't like unidentified noises, though. They usually mean trouble down the line, and while the car is being sproced up, now id the time.

It's going for some paint next week, after I repaired some rust damage, fitted good secondhand wings, and primed the lot. Hopefully, bumpers etc refitted and back on the road in a fortnight. I'd like to sort this first though, while it's still on the drive.

Thanks for your help too GC. :woohoo:
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Roundymooney
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Sat Apr 22, 2006 2:47 pm

Update:

Alternator bearing...

Not a big job for an auto-leccy I hope.
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