Ok, so, I'm new here as a registered user although I have used the threads here for many years as an education to particular problems I've had. Here is a issue that has me stumped.
The set up: 1976 Tartan Tock with Ford Lehman
80 aux eng. 7500 hrs to the best of my knowledge. Engine
I have hanged nothing about my raw water cooling
system to have started this issue.
The issue: Occasionally The raw water
system will lose prime and the pump will not clear it. Yes I have checked and changed the impeller twice now. The air lock occurs at the raw water
strainer which is below the water
line. The supply hose to the RWP is below the water line. If, on these instances, I crack open the strainer the air burps out water flows in and I'm back in business. It does seem that there is a vacuum on the strainer when I open it.
No water is leaking from the strainer, thruhull, seacock, or any hoses before or after the pump.
What in the world is happening?
Thanks in advance and I'm sure glad there is a world of folks out there smarter than me.