Remove the two bolts securing the crankshaft rear oil seal retainer to the oil pan.
Remove the holder and press the gland out of it.
Check the main oil line plug for leaks and replace if necessary. A new plug must be put on a sealant such as Loctite N 270.
Press a new crankshaft rear oil seal into the holder using drift 11 1 260 with handle 00 5 500.
Fill the sealing lips of the crankshaft rear oil seal with grease.
Apply sealant such as Atmosit or Curil K 2 to the mating surfaces of the oil seal holder and oil sump.
Install drift 11 2 213 on the crankshaft and fit the oil seal retainer onto the drift.