Head Gasket Change

Pressure gauge in the cabin Teed into the heater valve to heater hose.

'Original' (copper) head gasket showing signs of blow-by towards the water passages (lower). I replaced it with Payen.

Pitting and erosion of the flat parts of the head that are inside the combustion chamber on cylinders 1 and 2 (shown), no trace on 3 (shown) and 4.

40 thou overbore

1 and 2 exhaust valves showing white indicating the front carb had been weak recently, also signs on the head surface of blow-by, like the gasket

Petrol slowly leaked out from No.2 combustion chamber

Markings on the faces of the valve and seat, however this is No.3 inlet which wasn't leaking. This was probably the 'worst' visibly, there was nothing obvious on No.2 exhaust.

A few minutes with grinding paste removed it.

All valves lapped in, and the head face cleaned up.