I shamelessly steal Lars posting to trigger what I hope might be an interesting thread.
In the late 40s.I worked in a G.M. garage in Australia,another mechanic had a 39 chev.which started to use a lot of oil.Having pulled the engine down he found a loose gudgeon which had worn a wide groove in the cylinder.He could not afford to recond.the engine,so he filled the groove with solder.Everybody told him it would never vork.I worked in that place for another 8 months,he drove the car to and from work every working day and it didn't use any more oil than before the gudgeon came loose.I still find it hard to believe!
My dad was born in 1901and was in his forties when I came along . Her worked in a garage in Brighton in his teens and early twenties and this was one of his favourite tales. One of his first jobs was to take a pre-first war Douglas apart and find out why it only ran on the front cylinder. Simple, the rear piston had overheated and the rings were well and truly jammed in their grooves.
It was a cheap bike and - to dad's amazement - the boss found a nice bit of oak and turned up a new piston on the lathe. He wound asbestos string coated in graphite into the broad grooves he'd turned into it and drove the blind bored cylinder back into place with a wooden mallet.
Reassembled, it started and ran just fine and was sold within a few days. Some weeks later, the owner reappeared having driven the bike all over the south of England on holiday. Although the compression ratio was only about four to one and combustion temperature correspondingly low, eventually sufficient of the oak had burned away to bring the compression ratio to the point where it would not run on tickover. So the owner had removed the barrel to find out why.
Apparently they all stood dumbstruck in a line and roundly condemned the previous owner .......