The MD shop manual goes into great detail on how to install those shaft
seals. If the seals are purchased from Volvo (about $7 each) they should be
of the correct type of rubber for salt water and the garter spring should be
of stainless.

I always seem to end up changing any Volvo OEM pumps over to the Johnson
pumps but, if I remember correctly, the seals are the same size. The new
MD2B that I just installed in my boat came with a Johnson pump.

The biggest mistake a MD (or other) owners might make, is to allow or
intentionally blocking the weep hole in the pump mount housing.. This is
suppose to be a drain for any water that gets by the water side seal and
keep it from passing the oil side seal. The lip of the oil side seal faces
inward, towards the crank case and if water pressure builds up in the mount
housing, the water will leak right by a the oil side seal.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions