Had another failure - getting valve and valve seat sorted locally but the glowplug also failed and I'm after some advice.
This is the condition of the glowplug in the side that just overheated and failed (again). Its an air cooled 1974 German V twin diesel engine.
During the last hour of operation I can say there was a leaky valve (bent) so low compression and it was maybe sucking in a bit of sump oil through an oil leak in the rocker cover that was dripping onto the air filter.
Does it show classic signs of something being set up wrong.

Glow plug failure diagnostics...

Glow plug failure diagnostics...

Glow plug failure diagnostics...
A replacement is slim as its a 0.9Volt 40Amp beastie thats not fitted to anything I can find ad there was only one cross reference part I found but it was 10 mm to long. I can see me finding a modern slim glow plug the right length and hollowing out and threading the body of this one to take it