Coolant Loss

[BudgetGriff]

Hello,
This is my first question on this site so i'm gonna keep it simple.....
What is considered "normal" coolant loss for a '96 500 Griff? Mine seems to lose approx 1/2 to 1 pint per 500 miles.
I am just about to pull my engine apart to investigate possible camshaft problems and wondered if it was prudent to lift the heads off at the same time?
Any ideas?
Thanks.

[dougal]

Neither my 4ltr or my wifes 5ltr used any coolant whatsoever, check it's not being overfilled and get it pressure tested this should determine if and where there is a leak, easier and cheaper than removing/refitting the heads. I would have thought that if it was the gasket it would have been getting slowly worse until there was either water in the oil or vice versa?

[GreenV8S]

Normal coolant loss is nil. Maybe you have a small leak somewhere. Maybe just a pressure cap not sealing properly, maybe the rad starting to go. Possibly it's the head gasket, although you can test for this without removing the heads.

[UpTheIron]

GreenV8S said:

Possibly it's the head gasket, although you can test for this without removing the heads.

True for 99.9% of the time. (I would never normally comment on your expert views Pete you are certainly are much more knowledgable on these matters than me), but it some cases a small head gasket leak cannot be detected by any of the normal methods (pressure test, hydrocarbon test, exhaust gas analysis etc).

If you exhaust all sensible attempts to locate an external leak (which will be the problem 99% of the time), it could be heads off time.

Is the coolant loss significantly worse after a long fast journey? I had this problems and the 20 mile each way M25 journey (circa 50mph all the way) didn't change the coolant level. However a 100 mile 90mph stint would use several pints.

[BudgetGriff]

Thanks for your comments guys.
There doesn't appear to be any external leak and no water in the oil either. Car has been recently serviced and rolling roaded by Mark with no comments made in this respect.
It does seem to lose more water after a run, but i'd just accepted it as normal. Am only really questioning it now as it's about to come to bits!
Am beginning to think i've not bought the best Griff in the world, after a destroyed diff bracket, expensive rolling road, tappet/camshaft knock and now this! If it wasn't such a great car i'd sell it!
Thanks again.

[shpub]

Most likley cause is the rad and these can leak when stressed. The can move when the car is on the move and thus the coolent leak is not seen but the coolent level falls. Don't forget the obvious things like pipes and clips... Easy to overlook. Is the water pump dribbling? Again easy to not see.

Removing the heads is an expensive option as the head gaskets and bolts will need to be replaced. Don't reuse as that is asking for trouble. Cost is around £200 for the bits ish. Worth doing a hydrocarbon check first as this is usually pretty reliable.

>> Edited by shpub on Wednesday 26th November 10:25

[GreenV8S]

UpTheIron said:

True for 99.9% of the time.

Good point. I didn't mean to imply that the test was infallible, although a head gasket failure severe enough to cause that much coolant loss would probably show up quite clearly either via the HC test or water/oil contamination. At the end of the day these tests might indicate that you have a problem, but rarely prove beyond any possible doubt that you don't.

[simon.b]

Before you do anything else change the blue cap on the expansion bottle. It’s a standard VW ADUI part and not expensive, but these are prone to failure and difficult to spot.

My next favourite would be the radiator. I’ve constantly had problems and numerous radiator re-cores which only last about six months to a year and then fail again. The leaks tend to be small and as Steve said open and close dependant on temperature and conditions.

Mines leaking again now and has been for a few months, I intend to live with it until the water loss goes over the weekly top up and then invest in an ally rad which I hope will be stronger.

Cheers.

Simon.

[tiny]

Got the same problem and solution plan as simon.b - Peninsula are getting 4/5 ally rads made up so it may be worth a call to Richard Smith

[cyberface]

Mine's a 1996 and also loses a bit of water. The radiator's a bit iffy (corrosion at both bottom corners) but there isn't any obvious sign of where it's leaking.
If your rad doesn't look perfect then I'd suspect that.

I'd also be interested in stronger, longer life radiators!

[simpo two]

From my experiences, first check the blue cap on the expansion tank - the black rubber washer inside must be clean and grit-free, and I noticed last time it came back from a service they'd put a smear of vaseline or similar on it.

More seriously, keep an eye under the front of the car for tell-tale drips of coolant roughly under the front splitter. Before it gets that bad, though, the leaking coolant has to fill up a small trough in the GRP underneath the radiator - so get a torch and poke around under the radiator to see if there are any damp patches on the inside of the GRP.

[jam1et]

tiny said:

Got the same problem and solution plan as simon.b - Peninsula are getting 4/5 ally rads made up so it may be worth a call to Richard Smith

Mines in Peninsula having a service and new rad fitted. Wish I could have afforded the ally one but at more than double the price (aprox £400) I couldnt really justify it. Especially as it needs other work too that is going to cost a bit. They've got pics of the new rads on their website - look really nice.