Author Topic: Water Pump, Thermostat Or Air Lock?  (Read 1195 times)

Offline sirconical

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Water Pump, Thermostat Or Air Lock?
« on: 15 February 2007, 14:36 »
Hello all. I'm hoping somebody can help me because I'm having difficulty deciding what to do about my problem... whatever it may be!

My golf (not sure if it matters, but it's a mk2 8v gti) recently developed a split in the expansion bottle. This lead to topping up the coolant before every trip until it was fixed. I got a new bottle, drained my coolant system, flushed the coolant system and tried to refill it.

This is where things got interesting. I could only fit 2 litres of coolant into what my hains described as a 6.3 litre capacity! So I tried running it, squeezing the hoses, running it some more, squeezing some hoses more, nothing I knew of seemed to work. I drove it away from my friends house where I had been doing the draining. The coolant temperature guage was showing as half way. I started to wonder if it hadn't drained all the fluid.

The next time I tried to use it the temperature guage was at full whack within minutes of setting off. The little red warning light warning me was going crazy! I looked under the bonnet, and decided to loosen the cap to see what would happen (yeah, I know). Some coolant forced it's way out, so I put the cap back on. I tried squeezing all the hoses again hoping it was still just an airlock, but nothing happened. Except I noticed the top hose going into the radiator was very hot, whilst the bottom one was barely warm.

Any suggestions what it could be? I've been told it could be the Water Pump or the Thermostat. I've also been told it could still just be an airlock. And I've also been told the short drive I had to do to get it home may have even knackered my head gasket. :sad:

What should I do? How can I find out which of the problems it is?

Offline phil88

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Re: Water Pump, Thermostat Or Air Lock?
« Reply #1 on: 15 February 2007, 23:39 »
how about the radiator being blocked?

to test your thermostat you need to take it out of the water pump and put it into hot water it should open up if its working
« Last Edit: 15 February 2007, 23:42 by phil88 »

Offline rubjonny

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Re: Water Pump, Thermostat Or Air Lock?
« Reply #2 on: 16 February 2007, 17:04 »
unless you took the thermostat out, the block would still have been full of coolant.  Read my coolant how 2 post in the MK2 maintenance+info section
Hello my name is John and I'm a dub addict.