Blue is the colour...

[Stocky]

...of a very happy chap.

I mentioned in a previous thread that I thought the cooling system was pressurised and I may have a head gasket failure. I invested in a Block Tester and this is the result*. Phew!

IMG_0445 (Small).JPG

*Blue is normal. Yellow is HGF.

[new to this]

not seen a block tester before,have you found your fault yet,hopefully will be easier to find

dave

[Stocky]

I have no idea really. I can only think that it was an airlock. The heater valve was stuck closed when I bought the car, so I removed it, cleaned it etc and perhaps an airlock ensued once I refilled the system. Maybe this "released" suddenly giving all the frothing I noticed. Still not sure why this would have pressurised the coolant though. My next door neighbour owns a garage and has offered to pressure test the system.
I've now fitted a header tank (thanks Vmad/Chris!); one loss of coolant and an overheat is enough!

[martin]

I can hear the sigh of relief from here ! Good news indeed.