Oil on Tapered Fit

Oil is applied to metal to metal contact surfaces for lubrication and to prevent actual metal to metal contact where 2 surfaces slide over each other as in bearings, pistons, pins and bushes etc. When the lubrication breaks down the two metal surfaces touch and cause heat through friction. This can result in minute friction welds that break off and start the crazing seen on failed sliding components or the ultimate disaster of seized components that friction weld themselves together.

On a taper fit coupling movement is the last thing required. The two taper surfaces are forced together by the clamping nut to prevent movement. I know the lubrication may help future disassembly but I have seen expensive crankshaft and flywheel damage on large slow revving diesel engines caused by flywheel chatter attributed to the shock torque load of compression ignition on these components when an engine is working hard. Minute black particles, typical of burnt oil, were often seen in the damage area.

OK, other comments please I am not too old to learn.

Senlim

Senlim