Alternator Belt

Galaxyman

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Feb 25, 2010
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27
Someone please tell me the belt number/size for a 1987 5.7L 260 Mercruiser alternator belt. My engine s/n is B453879. Thanks alot! BK
 
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Galaxyman

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Feb 25, 2010
Messages
27
Re: Alternator Belt

Does anybody know? My belt does not have any numbers on it and I don't think it is the right size because is squeals when reving the engine even with the correct tightness. thanks.
 

Fishermark

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Oct 19, 2003
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5,617
Re: Alternator Belt

I don't think it is the right size because is squeals when reving the engine even with the correct tightness. thanks.

Is this a V-belt?

Why do you think it is the wrong size? If it was too long, it wouldn't tighten up correctly. If it is glazed, it could squeal. If that is all it is, you can take it to a parts store and they can match it up based on size.

if you are suggesting that maybe the width is wrong... then I don't know. Someone with access to part numbers will have to help. Sorry. :(
 

Fishermark

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Re: Alternator Belt

One more point to consider is that the squeal could be coming from the things the belt is driving - alternator or water pump for instance. Try removing the belt and see if either the pump or alternator feel like they are spinning freely.
 

Galaxyman

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Joined
Feb 25, 2010
Messages
27
Re: Alternator Belt

One more point to consider is that the squeal could be coming from the things the belt is driving - alternator or water pump for instance. Try removing the belt and see if either the pump or alternator feel like they are spinning freely.


I will definitely do that, thanks. The reason I think it is the belt is because i can smell the burning rubber after it squeals.
 
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JoLin

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Aug 18, 2007
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5,146
Re: Alternator Belt

I will definitely do that, thanks. The reason I think it is the belt is because i can smell the burning rubber after it squeals.

Right, if the bearing is failing on the thing the belt is driving. Belt has only 2 options when that happens- slip (squeal and burn) or break. Soon as that bearing fails for good, it'll break.
 

Fishermark

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Oct 19, 2003
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5,617
Re: Alternator Belt

Also make sure all the pulley grooves are clean, smooth, and shiny. If any are rusted or pitted, you can burn up / eat up your belt.
 
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