Greetings,
If I might add that you make sure that you
thoroughly clean all around the outer casing before removing the old oil seal cover (30) and two bolts (31).Attachment:
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The new oil seal should be fitted so that it is flush with the casing and as Richard says apply grease to help it slide into position. I use plumbers silicon grease around the case housing and the outer of the seal to help it slide into place. Put normal LM type grease inside the inner lips of the seal before inserting the collar. Inspect the collar for wear, a slight polishing effect is ok but if you can feel a lip then replace the collar too. A new cover plate is not always necessary but do apply a small drop of thread sealer on to the thread of the two retaining bolts.
TTFN
Hugh.