Many thanks for your suggestions, all of which I have tried. Geoff Pinch suggest that it could a sticking exhaust valve, which I thought made sense. I have both heads off and the valves are fine. New gaskets have just arrived and will be fitted tomorrow, then more head scratching. I have obtain all of my parts from O'Neil's Vintage Ford, whom I have found to be excellent.
#6782

Many thanks for your suggestions, all of which I have tried. Geoff Pinch suggest that it could a sticking exhaust valve, which I thought made sense. I have both heads off and the valves are fine.

New gaskets have just arrived and will be fitted tomorrow, then more head scratching.

I have obtain all of my parts from O’Neil’s Vintage Ford, whom I have found to be excellent.