Alternator or water pump rattle?

[ZuidWester]

All is well except...
At half revs or so, a slight rattle begins and engine speeds up just a bit at the same time, then settles down again. It's a bit annoying. I have tightened the belt and found very slight play in the water pump pulley but no water is leaking from around the pump (it's a BMC 1.5).
Any ideas?

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[alb40]

Have the same problem with my BMC 1500 only last week. The bearings in the water pump were worn causing the belt to slip and hence a slight revs increase / decrease. The pump was rattling because the impeller was knocking against the pump body inside due to the worn bearing. Replaced the pump on saturday and now working fine

Alex

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[steve_cronin]

May be a coincidence.....

but I'm only replying because of a similar situation with my son's car last week.

If this noise is better described as a "tinkle" rather than a "rattle" then look at the fins on the alternator cooling fan. It is quite easy for these to get bent so that they touch the front frame. Look for bright marks being made into the casting. If any fins are catching, they can be easily bent out again with a heavy screwdriver as the fan is usually only mild steel.

In my experience it takes many engine hours to ruin the alternator bearings and if the circulator pump is rattling then I would have expected it to have started leaking before now although it isn't unheard of for this not to be the case.

Steve Cronin



<hr width=100% size=1>The above is, like any other post here, only a personal opinion

 

[ZuidWester]

More a clatter

But thanks for the tip, I'll get in there with a crow bar and bend things about

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[bruce]

Re: More a clatter

take the belt loose, you should be able to feel the problem then, the bar should not be necessary till time to replace the belt.

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[ZuidWester]

That\'s my next move

Thanks for the idea. I'll try it.

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