Coolant level keeps dropping on the verge of giving up
As the title suggests I am regularly topping up the coolant as the level keeps dropping - its a 2003 Mini Cooper S.
So far I have changed the following on the coolant system:
- new expansion tank cap
- new thermostat & housing inc gasket
- new heater matrix
- new radiator
- new water pump (as this leaked when I pressure tested the system at 4 bar)
The expansion tank isn't showing any signs of leaks. I haven't done a further pressure test, a bit concerned I may break something else if I take it up to 4 bar again - at 2bar nothing happened last time.
I have also refurbished the cylinder head, and fitted a new head gasket and also replaced the oil heat exchanger with a replacement from ebay. I do get a bit of moisture in the rocker cover but I believe this is condensation, as I usually only use 1-2 times per week for a 6 mile run into work, or taking the kids into town - and also you can see water droplets on the oil cap, not the mix you would expect if the leak was at the head gasket still.
I have done so much work on the car and spent a fair amount of cash I really don't want to give up on it, but want to cure the leak so I can take in on another 2-3 trackdays this year.
Struggling to find any more answers, but wondered if anyone else had found a miracle cure, or if the problem could be something deeper in the engine and might need a engine swap to cure. Anything people, any ideas welcome!