Brother and I are now reaching the end of our tether with the old girl. Sorted the transfer box, and XYZ switch. With the recent hot weather decided to sort out the air con that needed re-gassing. Found a major leak on the top corner of the condenser - how it got punctured there I do not know but such is life. Replaced that and now re-booked in for regassing.

NOW the old girl has decide to play up on coolant.. After a six mile run found water rushing out of the expansion tank overflow. The coolant temperature gauge shows normal temp, The coolant is clean in the tank - no sign of oil or any other muck. The old girl was leaking some coolant with no obvious leaks but O-rings in the cap were looking dodgy so replaced them with new ones and the cap is looking past its best. So the first plan is to put the old ones back in and see if that improves it.

Don't think its the head gasket as there no sign of over-heating or contaminants in the water. Mayne the tank top needs replacing?? Any other suggestions would be appreciated. Cheers Mike

Could just be overfilled. My car expansion tank level settles down around the joining crack where the plastic is moulded.
If there is no sign of overheating, the cooling system is just not holding the pressure in. Are the hoses hard after a run?
Caps wear out as do the threads on the expansion tank.
I would fit a new oem cap. Put silicone grease on the tank threads to help get it good and tight.
You can get a pump and gauge to pressure test the system if you get desperate.
Aircon condenser will be corrosion from the outside. Some are sold that are just bare aluminium that will corrode in no time with salt on the roads.

Thanks for the response.. We were thinking on the same lines. Just to test the system brother took the old lady on a 30-40 mile round trip picking up some shopping along the way and everything behaved as it should. no overheating gauge showing all the right readings - low on motorway running - just over normal in traffic. AND NO MORE leaking from the expansion tank. Ordered a new cap as a precaution.

The condenser leak is an odd one. There was a hole in the vey top on the left side - it was a clear hole as if someone had put a screw in it. As soon as we pressurised the system the leak "almost blew me wig off". It is odd because it is under the rubber foam padding of the top slam panel. We reckon it may have been there for ages even years but was sealed by the rubber foam., only showing now as the rubber has aged..

Thanks again for the quick response, Cheers Mike

That's where they always leak. A combination of the rubber foam holding moisture so it can rot through the thin aluminium and vibration chafing though.