Screw Plug Oil Pressure Relief Piston

Screw plug for the oil pressure relief piston.
Type 1 engines.
Type 3 engines.

The oil pressure piston is held under tension by a spring and sits behind this locking screw in the bottom of the crankcase. On engines up to July 1969 there is only one piston (diagonally below the oil pump); after that two pistons were fitted, with the second on the flywheel side.

At the time Volkswagen chose a slotted screw, for which you need a very large screwdriver. Good tools are half the job, and this of course also applies to removing this slotted screw. Removing it with too small a screwdriver can damage the screw.

If your screws are damaged, do not refit them, but fit new ones!