Volkswagen Polo III (1994 - 1999) - 1995 1.4 Coolant not reaching radiator pump

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Tue 21 Oct 2008 11:01
1995 1.4 Coolant not reaching radiator pump - Dougy1302
Need some help! 1995 N Reg 1.4 Polo
Had a problem with engine overheating. Thermostat has been replced and new pump. The coolant isn't reaching the radiator, in turn the fan can't come on. We've checked for blockages. Does anyone have any idea why the coolant wouldn't reach the radiator when the main culprits have been replaced?

Any help greatly appreciated.

Edited by Dynamic Dave on 21/10/2008 at 14:33

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Tue 21 Oct 2008 13:05
Coolant not reaching radiator pump - mjm
Is the engine getting hot enough to open the thermostat to allow the water into the radiator?
Have you checked for air locks in the heater and main coolant circuit?
Does the heater get hot?
Is the thermostat actually working? (I know it's new, but -----)
Has the thermostat been fitted the right way round?
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Tue 21 Oct 2008 13:33
Coolant not reaching radiator pump - Number_Cruncher
Is there still an impellor on the other end of the water pump shaft?

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Tue 21 Oct 2008 13:40
Coolant not reaching radiator pump - mjm
I hope so, N_C, it's a new one, but you never know----
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Tue 21 Oct 2008 13:42
Coolant not reaching radiator pump - Number_Cruncher
Ah, missed that
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Tue 21 Oct 2008 14:04
Coolant not reaching radiator pump - Screwloose

If the hot coolant is circulating through the heater, then the pump should be OK. If it isn't....

How long from a cold start does it take to boil? What is the gauge reading? How did this problem occur?

A really bad headgasket leak can put so much gas into the coolant that nothing works properly.

Don't overlook the possibility of a pressure cap fault or an internally delaminating hose.
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Tue 21 Oct 2008 14:31
Coolant not reaching radiator pump - OldSock
You might try running it with the thermostat removed.

If you've checked the radiator for blockage, filled the system correctly to avoid airlocks and are using a new pump, it's hard to say what else is wrong :-(

Did the overheating develop gradually or suddenly?
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Tue 21 Oct 2008 15:01
Coolant not reaching radiator pump - injection doc
thermostat housing will have a broken lug in it!. Replace the plastic thermostat housing & it will fix it.

There is a lug in the top of the plastic housing that punches through!
I Doc
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Tue 21 Oct 2008 15:26
1995 1.4 Coolant not reaching radiator pump - Dougy1302
Thanks for your help everyone! Any more ideas? I'll let you know how it goes...fingers crossed!
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