Fitting the crankshaft

I remember quite clearly my anxiousness when it finally came round to fitting the crankshaft back into my Vespa PX 200 engine.  And despite that previous experience going pretty smoothly, I didn't feel any less anxious this time round either.
I use the tried and trusted method of heating one part of the assembly to expand it, and freezing the other part of the assembly to contract it - then if you are quick enough to maintain the temperature differences, the two closely fitting parts slide together relatively easily - the key phrase here being "if you are quick enough" - it is all a bit of a 5 minute rush and panic.

I think much of the success in fitting bearings and crankshafts is in the preparation - having pullers and blocks ready to hand to help the quick process of fitting fully home.  I made up a whole bunch of plates to spread loads, and tubes to pull down on and laid them all out neatly ready for action.
So with the two bearings just out of the freezer, and a blow-torch on the engine casings (hot enough so you cant touch, but not so hot that things are glowing) the bearings went home beautifully.
For those who are interested - I made great effort to ensure I didn't forget to put back the "compensating washer" before dropping the main bearing in.  I am not sure how I should have determined if this washer was still doing the right amount of 'compensating' (or indeed what it is compensating for) but I decided to simply put back the washer that I took out when I unassembled the engine - it was 0.5mm thick.

Next step - fitting the crankshaft into the new bearings - this of course requires the closing of the two halves of the engine case, so fitting the new gasket all takes a little more preparation and time

The crankshaft only needed a couple of hours in the freezer to chill.  With the larger engine-case half suitably warmed by blow-torch, and the bearing heavily lubed up with grease it was a relatively quick and easy fitting, though it did need my prepared puller to draw it home properly.
To fit the other side bearing, the engine cases have to be closed, so while I was Red-Hermatiting the gasket the crankshaft was slowly warming back to ambient temperature which would mean that I wasnt going to have the same expansion/contraction advantage as I did on the first bearing.  However, I still heated up the smaller engine-case side and bearing and sure enough, it went home without too much fuss or bother.

I have to say, it was a great relief as I tightened down the engine case bolts to feel the crankshaft spinning silently and freely.