Mk4 Golf Water/Coolant Pump change?

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Thu 28 Jul 2005 19:27
Mk4 Golf Water/Coolant Pump change? - nozmeister
My Mk4 TDI Golf is due for a 60K service in the next month or so. At 60K miles the Cambelt is due for replacement and I intend to get this done.

I've read a little of Golfs having problems with the water pump as the plastic breaks down over time.

As the cambelt needs to be replaced and this is quite a bit of work is it worth getting the pump done at the same time? Any ideas on how much this might cost?

thanks in advance...
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Thu 28 Jul 2005 21:40
Mk4 Golf Water/Coolant Pump change? - HarlequinVW
I have heard this too. I am just about to do my cambelt so have invested in a replacement water pump from GSF carparts. The replacement pump is made by ruville and has a brass impeller interference fitted onto a stainless steel shaft. My mk4 is a 2.0 petrol and the pump cost was about £24.
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Sat 6 Aug 2005 15:07
Mk4 Golf Water/Coolant Pump change? - HarlequinVW
there's a good write up on the whole job here:

www.clubgti.com/forum/forum_posts.asp?TID=80888&PN...1
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Sat 6 Aug 2005 20:52
Mk4 Golf Water/Coolant Pump change? - Number_Cruncher
The picture showing the local corrosion between the plastic imellor and the stainless shaft is very interesting.

It would appear that the extra volume occipied by the corrosion products is swelling the inner diameter of the impellor, over-stressing the impellor hub, and leading to fracture.

Is it an interaction between a chemical in the plastic and the stainless which causes the corrosion, or a more complex interaction between plastic, coolant and stainless steel?

Although I don't know much at all about the conditions under which stainless corrodes, I do know that some grades are not tolerant of an environment rich in chlorides.

Number_Cruncher
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Sat 6 Aug 2005 21:11
Mk4 Golf Water/Coolant Pump change? - HarlequinVW
The impeller would appear to have a mild steel bush, the stainless is fine. There have been lots of failure reports on:

www.uk-mkvs.net/forums/38/ShowForum.aspx

and even reports of VW glueing the impeller back on......
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Sat 6 Aug 2005 22:16
Mk4 Golf Water/Coolant Pump change? - Mackay78
Hi,

Recently I had the cambelt changed on my 99 Pasat TDi at VW dealer and I requested the water pump to be changed at the same time, VW charge £26 + VAT for the pump, PART NO 028121004X, very reasonable I think and most VW/Audi models from 1997 on use the same pump.

Paul
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