The engine in the 250 LM comeswith loads of internal components which could very well be left out, because no one would ever notice. However after some deliberation I decided to assemble as spelled out, and document the heck out of it.
The pistons are cast in one piece, meaning the crank has to be built up. This leads implies lots and lots of bits, including wrist pins made from brass wire.
Once assembled, the crank, rods and pistons flap around a bit. Also part of the build-up is 5 of the 7 main bearing blocks which are sadly not split.
The engine block being made in two halves, it is impossible to insert the assembled crankshaft with 12 rods and pistons into the assembled block all in one go. Rather it is necessary to insert 6 pistons into one half of the block, carefully gluing the main bearing blocks to the block but not the crank, then carefully slip the other half block over the remaining 6 pistons and glue it all in.
Of course I tried to turn the crank to see how well I assembled the whole thing, but it went a quarter turn before jamming, and applying a bit of torque caused the crank to break. So the last journal, carrying the rods for the last two cylinders, is now independent of the forward five journals carrying the remaining ten rods and pistons. You have now been warned: don't ask me to assemble your crankshaft if you expect it to turn.
The lower crankcase and oil pan are now in place and the crankshaft is forever sealed in there where no one will ever see it again.
Next the valves and valve springs (made of white metal, sadly) went into the cylinder heads, and assembled heads were attached to the block with the appropriate gaskets.
The next step involved adding the camshaft drive gears in their front cover (also now hidden forever), the flywheel housing and the intake manifolds before painting the whole thing with a mix of 1/3 dark aluminum (ZP-M1004) and 2/3 light aluminum (ZP-M1001) from Zero Paints.
Next were the camshafts, one per bank, and the rockers, each on its own rocker shaft mounted between two camshaft bearing blocks. For some unfathomable reason, the cam bearing blocks are not fitted to the head with a precast dowel and socket approach, but with 48 bits of 0.5 mm diameter wire, each 5 mm long.
Finally the cylinder head internals were covered with Tamiya's brown panel line accent colour to mimic oil residues; I wiped the worst off the rollers on the rocker ends to mimic the machined finish here.
This will never be seen again once the cam covers are on. However, it is now documented that I actually did it.
And that's it for now.
