water pump help??

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and1_e30
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Post Mon Sep 16, 2013 2:23 pm

hi my parter has just got an e30 its a m20b25 engine it overheated on the way home so i got it towed back, im going to do a compression test but wondering if the water pump has failed, how can i check to see if its gone? i know i can feel the top hose but if i take the alternator belt off and the fan can i spin it freely aswell?

cheers

jon
Speedtouch
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Post Mon Sep 16, 2013 2:51 pm

There should be very little play in the pulley - waggle it back and forth to check.

Unlikey that it will have suddenly failed, without prior warning.

If you do need to replace it, BMW dealers give you about £20 back for the old one, even if it's a non-BMW part!

http://www.e30zone.net/e30zonewiki/index.php/Cooling
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
Rtaylor2208
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Post Mon Sep 16, 2013 4:39 pm

if your changing the pump you may as well do the cambelt at the same time as it has to come off to change the pump.

To give you an idea if its at least flowing properly, the top hose should be much warmer than the bottom.

But overheating can be an air lock, knackered viscous, sludged up rad, blown gasket etc as well.

the link speedtouch posted will cover all the bases.