UPDATE.......

About 5 degrees c here today....

Local mechanic offered to spray a little Easy Start into the intake while I cranked engine. Engine started ok. Turned it off straight away, cranked it over again and wouldn't start. Sprayed another minimal amount of Easy start in and engine started ok. This time I drove it and let it warm up properly before turning off. Engine started straight away on it's own, and started ok again after 20 minutes cooling down, and again after an hour. Also after 2 hours it started, and even 5 hours later it started, although each time needing more cranks to get going.

My basic thoughts are as engine was warm enough it didn't need the glow plugs to start. I will check tomorrow morning but guessing it won't start as almost freezing here over night.

Any thoughts or conclusions from today's tests?

(as an aside I don't like using Easy start and 2 squirts is maximum and I plan not to use it any more.)

My plan is to replace glow plugs once I can get that damn intake manifold off - got it 99% off but can't release the metal clamp intake at the front!