Coolant dumped on driveway- advice/ reasons why?

[AllezWasps]

On the two most recent occasions that I have checked the coolant levels on the Cerb (cap unscrewed- level checked and as it should be so no further coolant/ water added)I have then either gone on a short run in the car or turned the engine on and let in run for a few minutes and on both occasions, the car has dumped it's coolant all over the driveway.

The car isn't overheating but it obviously doesn't like the cap being taken off for some reason- On the first occassion after the run- it lost what looked like pretty much all of the coolant and on the second occassion when the engine had been running at idle for about 5 mins I would say it lost about a litre or so.

Has anyone else experienced anything similar and/ or does anyone have any thoughts as to why the car might be doing this?

[Gray_101]

Mine did this the other day, while I was setting the throttle pots. The engine was not up to temp

As I've never known a thermostat to stick shut, I'm guessing it's head gasket related,,,,, Glup, or maybe just a case that I over filled the header tank when I topped it up the other day ? I'm not sure

[Pied Piper]

Is it dumping it from the expansion tank?

If so it might be as simple as a new cap needed, the rubber does perish/squash/get damaged over time. It was this on mine, it did it at Dover on the way to South of France.

[G20RG B]

Make sure the cap is done up tight, and maybe you are putting to much coolent in and it is finding it's level?

[Gray_101]

Just been out to the garage, my header tank is still about half full.

I gave the AJP a serious thrash yesterday, so I'm gonna top up the header tank to the full Mark again and see if it does it again.

Mine ejected it's coolant from the cap, may be it's had it, or I didn't tighten it enough.

[AllezWasps]

G20RG B said:

Make sure the cap is done up tight, and maybe you are putting to much coolent in and it is finding it's level?

Yes- cap was on tight enough and the coolant level was pretty much spot on, hence my not adding any additional liquid.

My thought was indeed the expansion tank but why would simply taking the cap off and then replacing it without adding anything else result in such (particularly on the first occasion) a heavy loss of coolant.
Interestingly, having lost the coolant on both occasions and then refilling there were no further instances.

Matt

[BCA]

Isn't there a valve underneath the tank that opens to stop/ lessen the likelihood of you being showered in scolding water, and pours it out underneath?? Or something like that?? I can remember something like that, not sure if that means its a knackered expansion tank or if it is just meant to work that way? It was a few years back when I last looked around it.

[Ireland]

Have you done anything else to the car recently that might be causing the problem?

I fitted a new stat to mine and had an issue with overheating and blowing water / steam out.

It turned out there was debris inside the new stat that was preventing it from opening.

Once I cleared it out everything was fine.

Could you possibly have some sort of a stat issue the won't be obvious with a cold engine?

[AllezWasps]

Ireland said:

Have you done anything else to the car recently that might be causing the problem?

I fitted a new stat to mine and had an issue with overheating and blowing water / steam out.

It turned out there was debris inside the new stat that was preventing it from opening.

Once I cleared it out everything was fine.

Could you possibly have some sort of a stat issue the won't be obvious with a cold engine?

Nothing has been done to the car recently that would result in the 'coolant issue'. It's due in to Str8six for it's service in a few weeks. I'll obviously put Jason in the picture and hopefully he'll be able to have a bit of a rummage around (expansion tank area) and see if there are any issues that need addressing...

Matt

[Mr Cerbera]

Sorry A-W,
This'll probably be of no use but I traced a cooling system leak problem on mine to the tiny 'Y' joint that lives between the header tank pipe and the two flexible pipes that supply/feed the exterior header pipes.
The original is plastic, like that fitted to garden hose distribution systems but one of the TVR parts' suppliers has one in Brass (Sorry, forgotten who !)

Good Luck

Also, if you've had a big leakage then I find it's best to bleed the system whilst on an upward incline to fully remove the air locks.
Sorry if I'm being re- re- repetitive

Edited by Mr Cerbera on Tuesday 3rd May 21:46

[scotty_d]

BCA said:

Isn't there a valve underneath the tank that opens to stop/ lessen the likelihood of you being showered in scolding water, and pours it out underneath?? Or something like that?? I can remember something like that, not sure if that means its a knackered expansion tank or if it is just meant to work that way? It was a few years back when I last looked around it.

Had mine out not too long ago think it's just the cap that blows off if the pressure builds.

Scott

[AllezWasps]

Thankyou Mr C,

No- you're not being repetitive at all. Thanks for your thoughts. I guess it's a case of 'it could be one of a number of things'! I still find it somewhat odd that the only times it has ever done it (touch wood) is just those two times I have unscrewed the cap. Other than that it has sat (as happily as a Cerb ever can sit) in traffic, the engine temperature has built up, fans have kicked in and despite the car getting very hot, it hasn't boiled over.

Matt

[AllezWasps]

Thankyou Mr C,

No- you're not being repetitive at all. Thanks for your thoughts. I guess it's a case of 'it could be one of a number of things'! I still find it somewhat odd that the only times it has ever done it (touch wood) is just those two times I have unscrewed the cap. Other than that it has sat (as happily as a Cerb ever can sit) in traffic, the engine temperature has built up, fans have kicked in and despite the car getting very hot, it hasn't boiled over.

Matt

[FarmyardPants]

Did you fill up the windscreen washer fluid at the same time, that certainly does piss out via an invisible overflow

[AllezWasps]

FarmyardPants said:

Did you fill up the windscreen washer fluid at the same time, that certainly does piss out via an invisible overflow

Absolutely not- not with Engine coolant or windscreen wash fluid

[Jimii]

I would say you have some air in the system, could be caused by a small leak somewhere.

[Mad Mark]

undo the bolt on the top and drivers side of the radiator check the level from there and also try the bleed valves on the two coolant bars under the air boxes.

[AllezWasps]

Mad Mark said:

undo the bolt on the top and drivers side of the radiator check the level from there and also try the bleed valves on the two coolant bars under the air boxes.

Thanks Mark. I'll have a look this weekend.