OK. I have a definitive answer to the problem now, so here goes, its fucking obscure, but I take full blame.. keep the paragraph below in mind, it becomes important later. This engine was a military motor out of a WW11 tracked vehicle called a Bren Gun Carrier. the engine was mounted amidships and difficult to get to, and as is typical with military stuff, they improved upon the civilian stuff, in this case adding a FULL flow oil filtering system. Now '39 mercs on the other hand, had NO filtration. As i pulled it down it was obvious there was no oil at all reaching the front two main bearings, and consequently also the front six conrods bearings, so at this point Im convinced something has blocked the main gallery.The rear main is fine as it is fed by its own direct drilling from the oil pump gallery. Now the frustrating thing about the design of this engine is that the main gallery tube ends at the fuel pump pushrod bush, wraps around it ,and then carries on to the rear of the block where there is a plug, so you cant actually see straight thru it without somehow removing the fuel pump pushrod bush(which is close to impossible) SO my thoughts were ,'something has blocked the area around the pushrod bush' so i worked out how to block all the other passages and blow carb cleaner thru with air, and that worked fine, nothing but clean fluid came out. Damn. thats not it. then I thought about the supply to the end of this tube and traced all the passages back, thinking there must be a direct passage back to the oil pump cavity, but no, there isnt! the main oil supply goes up thru the little hump above the bellhousing, where you screw in an oil pressure gauge,then travels back to the centre of the engine, and down the main gallery. Deep inside this little hump is another gallery plug, that is placed there on Military engines to direct all the oil out thru the filter and then it re-enters on the other side of the plug. This plug is in place on my engine. I put it back in, assuming it was part of the way the oiling system worked, but of course with no external filter to bypass this blockage, no oil reached the front of the engine. Lack of understanding of the differences between '39 military and civilian engines killed my motor, Making it one of the last casualties of the second world war!! The damage is as follows.. Main bearings-toast conrod bearings-toast bore and piston Cyl 1 are fucked.I think this is due to bearing material being thrown into the bore from no1 main..its pretty ugly. the rest of the pistons show some wear, which has me puzzled, i will post pics of these on a new thread.. lifter faces scored, can resurface.cam looks ok. rods are all fine.that moly assembly lube is good stuff! its all that saved them. the crank should be fine with a polish. if it wasnt for the piston and bore i could have this thing back together in a week. Im halfway contemplating a set of Ross forgeds and going out to 0.060 whats another fucking thousand dollars right?? Im angry at myself for missing this, but it at least proves i didnt make any obvoius cock ups, just a pretty fucking obscure one.