My mate bought a very cheap Mini. He spent a long time getting it back on the road, mainly due to rust and loose running gear. The motor wasn't brilliant, but it didn't smoke too much, and with a 3.65:1 diff, it was very quick off the blocks.

Exactly two weeks after he got the car re-registered the engine blew up. He let out the clutch after going into second gear and there was an enormous bang, clunk clunk clunk. He shut down the engine. Then he restarted it and even drove a few metres uphill. After he shut it down again, the flywheel, which was only held by one bearing on the crank, jammed against the starter motor, and the engine would not start again.

This is what we found after a night of drinking beer and taking apart an engine: