Strange coolant problem

[ChasNott]

Hi

I have a MK II 1997 Stag with

New 3 row rad

New thermostat Genuine Land Rover RTC3692

New Pressure Cap 20lb GRC222

But after going for a good run the expansion bottle is full (but it is half full before I set off). If I remove the hex on the radiator (after it has cooled down!!) it is low. If I remove the expansion bottle and put it above the radiator then the levels sort themselves out.

Strange...

I shall run it and see what happens but any thoughts are appreciated..

Charlie

[Danny]

Hi Charlie,

The liquid level in the expansion bottle should increase when the engine is hot and then as it cools again the water should be drawn back into the system. It sounds to me like you have air ingress into the cooling system somewhere. I had the same problem with my car. what you need to do is check the tightness off all the jubilee clips and connections.

Danny

[marshman]

As Danny says for all the coolant to return to the engine/radiator the system must be totally airtight. If it is not then as the engine cools air is drawn in rather than the coolant from the expansion bottle. Common leakage points are any of the hose connections but also the hex plug on the radiator and also brass neck on expansion bottle or the radiator cap. If you have replaced the thermostat then the joint could also be the source. One way of testing the system is to disconnect the expansion bottle and attach a tyre pump to the pipe into the rad. You can then pressurise the system and listen for any leaks.

Are you sure their are no airlocks? Did you fit the thermostat with ghe air bleed hole at the top?

Roger

[flying farmer]

Definitely an air leak problem, if tightening all the hose clips doesn't cure it then it may well be the water pump seal. These suck in air even easier than they lose water.

Fitting a header tank fixes this sort of problem.

Neil

[Danny]

Neil,

Thats what I did - fitted a header tank but I did not want to be the first to mention it.

Danny

[Guest]

Hi

I have a MK II 1997 Stag with

New 3 row rad

New thermostat Genuine Land Rover RTC3692

New Pressure Cap 20lb GRC222

But after going for a good run the expansion bottle is full (but it is half full before I set off). If I remove the hex on the radiator (after it has cooled down!!) it is low. If I remove the expansion bottle and put it above the radiator then the levels sort themselves out.

Strange...

I shall run it and see what happens but any thoughts are appreciated..

Charlie

That was hanging around a show room for a very long time

Does sound like an air leak, worm screw clips or brass neck on the expansion tank?

Jason

[Staggard]

Neil,

Thats what I did - fitted a header tank but I did not want to be the first to mention it.

Danny

I really really hope nobody mentioned a H/T smiley-shocked003[1].gif

[flying farmer]

I really really hope nobody mentioned a H/T [ATTACH=CONFIG]33487[/ATTACH]

Nothing quite like poking the hornets nest!

[GDPR]

I mentioned the war once but think I got away with it.....

[38rover]

I really really hope nobody mentioned a H/T [ATTACH=CONFIG]33487[/ATTACH]

Graham I doubt it was the H.T. leads

[ChasNott]

Thanks for your replies. It was the top hose to rad jubilee clip.