Perkins Loses Prime

[timmfive]

for possible solution, see here:
Solved! Overheating Yanmar 3GM30 due to Johnson raw water pump not priming. - Yachting and Boating World Forums

[Chief Engineer]

Most strainers will function with a little air in them as the air is above the fluid inlets and outlets.

If you are consistently losing prime you have an air leak in the inlet side or and obstruction on the inlet side and the air is sucking in thru the seals/fittings....or the seal in the pump.

[PaulvR]

If it happens in rough seas, the intake might be too far outboard, and it sucks air in a chop, or a swell, depending on the size of vessel?? Should be self-priming though..

[Lepke]

You realize this is a 9 year old thread? I hope he fixed it by now.