Thursday, March 8, 2012

Engine rebuild: part 1.

The engine has been rebuilt! Here is part 1.

here we see the crankshaft, apparently all ready to go, yet hiding a sneaky surprise ready to bite us in the ass before long.

A new roller bearing on the drive side... standard size big end shells, wrapped in wonderful oily parchment.

Testing the oil passage on the connecting rod.

But what's this? just as he started tightening the second connecting rod onto the crankshaft, Peppe noticed it wasn't turning freely.
Off comes the connecting rod, the new big end shells are inspected and we see a hairline scoring that wasn't there before. Magnifying glass at hand, Peppe discovers a small nick on the main journal, which definitely wasn't there before we handed the parts to the machine shop. Who knows what happened, but you'd expect better from a machine shop, right?
The imperfection is gently massaged away with a small file and some very fine sandpaper...

...the torque wrench is set carefully to 22 ft lbs
and both connecting rods are in place correctly.

The new timing-side bush.

ALL this scattered ground zero of parts will soon be a compact, purposeful engine.

The back of the cylinder head. Peppe did some serious cleaning on the inlet manifold, which I had forgotten about when I cleaned the crankcases. You'll see it in part 2 of the rebuild.

The camshaft is back with a new thrust washer.

I cleaned the cylinder barrel and found the paint to be in better condition than I remembered.
Peppe scraped away some surface rust here and there with an exacto knife and I gave it a couple of coats of heat-resistant paint. So far it looks pretty good!

Just as we were getting ready to put the two halves back together and of course *after* applying the gasket cement, we noticed this other surprise, again courtesy of the ham-fisted, dim-witted twit at the machine shop:
I know for a fact that this used to be intact. This is a pretty major inconvenience and it did cost us quite a bit of time. Luckily the man is handy with a lathe...
...and a set of dies.
Going mano a mano with a piece of round stock to turn it into a new stud.

Pressure testing the sump scavenge passage.

Grabbing the bunny by the ears.

Here we go:
Great stuff.

Timing gears back in place.

Ready to dish out some road-burning mayhem, watch out!

Here's a new paper gasket for the oil pump. It's from a complete NOS set I bought years ago.
Oil pump and worm drive back in place.

This is the oil pressure release valve:
doesn't it look like some sort of apparatus from a Jules Verne novel?
Back in place.

Now for the gearbox.


Post a Comment