Vauxhall Astra G Diesel (1998 - 2004) - 1999 2.0 coolant mystery!

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Fri 15 Aug 2008 20:06
1999 2.0 coolant mystery! - warriormonkey
Hey all,

I've got something here that I can't quite get my head round. It looks like i've got a leak on my 1999 Astravan. The Engine started running very hot yesterday so I stopped, let it cool, checked the expansion tank and it was empty. Judging by the amount it took it had all gone. I checked the oil cap, the exhaust and for bubbles in the expansion tank and no sign that the HG was about to depart, so tentatively ruled that out. However, when she's cold if I fill the expan' tank, once the lid is on she'll continue to drip for a while then stop. If I start the engine she'll start to drip again, but after a while, once the engine has been off, she'll stop again. However, if I open the expansion tank cap, even momentarily, she'll start to drip again. The problem is that I can't see where the drip's are coming from. When running at speed she's going through coolant at some speed, but from where? It's not the rad because it's too far back. The coolant's coming out very very clean, no oil, no rust or debris etc. Do you think it could be the bottom hose, or maybe the water pump? Why does it start again when the cap is removed? Someone suggested Radweld but i'm really not to keen on that idea to be honest. I would be extremely grateful for any thoughts.

Monkey

Edited by Pugugly on 15/08/2008 at 20:09

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Fri 15 Aug 2008 23:57
1999 2.0 coolant mystery! - Peter.N.
I would check the expansion tank overflow pipe, try putting a container under it and then going for a drive. If you have head gasket leakage its always going to be much worse when the engine is under load.
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Sat 16 Aug 2008 13:59
1999 2.0 coolant mystery! - warriormonkey
It does drip when the engine's running, but it doesn't seem to flow out, just drips quickly if that makes any sense. When everything is off, and after the expansion cap has been shut for a while the dripping stops completely suggesting that some kind of vacuum is being formed inside somewhere.
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Sat 16 Aug 2008 14:05
1999 2.0 coolant mystery! - Screwloose

Parfectly normal; but where is it dripping from...?
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Sat 16 Aug 2008 14:13
1999 2.0 coolant mystery! - warriormonkey
I can't properly see at the moment, it's not the rad as it's too far back. On initial inspection it looked to be coming from a clad cable, but that just seems to be providing something for it to flow down. It looks like it's somewhere in the middle underneath the front of the engine block, but I cannot get a better look at the moment. There was what looked like a metal pipe or casing that this cable ran partly along that seemed to be weeping in a corner. That doesn't really make any sense does it. Sorry I can't be clearer.
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Sat 16 Aug 2008 14:26
1999 2.0 coolant mystery! - Screwloose

Leaks can come from almost anywhere; the only way to find them is the good old MkI eyeball.
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Mon 18 Aug 2008 12:04
1999 2.0 coolant mystery! - piston power
Coolant pressure test is required

Then you will see the leak!
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