http://www.youtube.com/watch?v=qAGz4i2_Iuk

the turbo was found at a salvage yard on a 1L diesel industrial engine. His lawnmower broke and his mum was going to buy a new one, this was his attempt at fixing it. Engine was a 5hp Briggs and Stratton Single 4stroker.

Enjoy.

first off its important to point out that the reason the lawnmower was broken is because its rings were worn and it lacked compression.

Its a 4stroke single B&S ~250cc engine. The lubrication system in these consists of a sump and a little "water wheel" of sorts that runs off the crank. this water wheel when spinning essetially splashes oil everywhere in the crankcase lubircating the crank etc. This particular has a OHC setup with is lubricated by having the oil be picked up by the worm gears and propogated to the cam mechanisim. the cylinder is also laying on its side.

As far as I understand, the lubrication system relies on the extra pressure of the turbo creating a positive pressure in the crank case which forces the oily-air misture up the yellow tube into the turbo, where it leaks out of the seals into the exhaust housing. Its not very effective, but it works somewhat and it wasn't really designed to be reliable.