Harry Ferguson, right got it (i think), thats before they merged with Massey. Thanks i wont forget that from now on.
I couldnt resist and ive taken the head off. A couple of tips for anyone doing this in the future including myself. Remove the bonnet and undo the fan belt and water pump and govenor clip, its all very easy just a few bolts. The push-rods can come out before or after lifting the head. Ive just left mine in. It looks as though they work by sitting in a cup that rides up and down from the crankshaft.
I lifted the head off by myself, heavy but not excessively- approximately 40kg i would guess.
Seems like you folks suspected diagnosis could be right. The headgasket looks fine, no cracking in the liners, the bores look fine with no scratches and all the piston domes have hard carbon on them, not excessive and not that soft stuff which indicates issues.
There is a tiny graze on top of the number one piston, maybe something went through the air intake, i cant even feel it with my fingers and its only piston number 2 with low compression and that looks fine. Im suspecting it will be something to do with the cylinder two valves now as well. Ive filled the cylinders up with diesel so i can give them a polish and all of them are holding the diesel levels constant so if piston 2 had bad rings i would expect that cylinders level to drop.
The engine is very dirty so im going to do my best to clean that all up, gunk in lots of places.
The way to tell which cylinder is what in those photos of the block is to look at the alternator which is near the front.
The head is now on the table at home and when i get back early next week i will update on what i find. Any tips about how to inspect a cylinder head, valves would be appreciated as this is my first one (as ive clearly displayed!)