This is a problem that can occur on any
engine, not just the D2-55. If the sea
water pump has any wear on the impeller, cover or wear plate it can be difficult to get the prime going again. Especially with a long convoluted system.
The
pump on the D2-55 is made by Johnson
Pump, and they offer two different impellers for the pump..... the standard one and one that is .015" thicker to accomidate wear in the pump.
Part numbers are:
Standard impeller# 09-1027B-01
Oversize impeller#. 09-1027B-10
Hope this helps..
DougR