BMW 5251 Service Manual page 326

Lubrication System
To test switch, connect an ohmmeter between terminal in
switch body (arrow) and ground. With engine off, there
should be continuity. With engine running, oil pressure
should open switch and there should be no continuity. Re-
place a faulty switch.
CAUTION-
Keep in mind that low oil pressure may be preventing the
switch from turning the light out If the light remains on while
the engine is running, check the oil pressure as described
earlier. Do not drive the car until the problem is corrected. The
engine may be severely damaged.
Crankshaft rear main seal replacement requires removal of
the transmission and flywheel.
Crankshaft rear main seal, replacing
(&cylinder)
-
Remove transmission. See 230 Manual Transmission or
240 Automatic Transmission.
-
Manual transmission vehicles: Remove clutch pressure plate
and disc. See 210 Clutch.
-
Remove flywheel. See 210 Clutch or 240 Automatic Trans-
mission.
-
Drain engine oil.
4
Remove seal carrier bolts from oil pan (arrows). Loosen all
oil pan bolts.