Air in Raw Water System?

[NYSail]

Make sure no air in strainer...... then rev engine a bit to pull

Good luck
Greg

[Pearson Stu]

Originally Posted by BozSail

Well... problem has been solved. The solution is embarrassing, but I'm posting it in the hope that someone else may avoid my dumb mistake. When I installed the new water pump">raw water pump over the winter, I installed it in the position that seemed to be appropriate. The inlet and outlet fittings were at the top of the pump, as was the cam on the inside cylinder of the pump. It did not pump raw water properly in this position (hence my reason for the original post). So... I decided to try mounting the pump upside down so that the inlet and outlet fittings were on the bottom of the pump. I then started the engine and had a healthy flow of raw water coming out the exhaust. I let the engine run for 20 minutes to bring it up to operating temp. All is good. I'll certainly remember that if I ever have to replace the whole pump again. [emoji5]
Thank you to everyone who offered their suggestions. Sometimes, I guess I learn things the hard way.

A hard won victory is still a victory -Congrats BozSail. I'm sure we could all contribute to a new thread on embarrassing repairs.

[redneckrob]

Originally Posted by sailah

I run with large intake hose up to cockpit. The year it happened to me I was pumping antifreeze thru during winterization. I shut down too early and it siphoned out the rest of bucket which then backs up through exhaust elbow and into any open valves, down into cylinder. Vs normal operation it needs to suck it up through the strainer.

At least that's how I *think* it happened. Because I was questioning myself if I did it right all winter since I know better. So in the spring I made a note to myself to pull dipstick and sure enough it was chocolate milk and smelled like antifreeze. Then I decided to be real careful and pull all glow plugs before cranking engine. Had a couple blast of antifreeze come flying out so it was sitting in at least 1 cylinder all winter.

I had to run 4-5 oil changes back to back to get it running clear oil again.

Same way it happens if you try to start the engine too much, the pump pumps water but it doesn't have combustion exhaust to expel it.

So that's why I always let pump run dry for 5-10 seconds after the last bit of antifreeze is in engine. I replace my impeller every year anyways. Running it dry is probably overkill but that's my system to know for sure I won't have any head pressure.

At end of season I finally dealt with my bad head gasket and there were no signs of cylinder wear so I assume it was fine.

My uncle was not so lucky and cranked him Yanmar over with water in cylinders, bent some con rods. Said he could hear water sloshing around when turning over by hand

Always take safe route before cranking a diesel is my plan.

I get it. The answer to that is pretty simple, just put the bucket at basically the same level as the intake was initially and it will be impossible for it to siphon. Seems like a much simpler solution?

[sailah]

Originally Posted by redneckrob

I get it. The answer to that is pretty simple, just put the bucket at basically the same level as the intake was initially and it will be impossible for it to siphon. Seems like a much simpler solution?

Life is never that simple. The only way to get a bucket to that level is by putting it down in cockpit locker. Or on cabin sole. Either of which means a wet boat.

When I winterize my boat I have garden hose feeding water into bucket continuously so the bucket overfloweth for 30 mins to allow the fuel polisher to circulate the over winter mix and the get rid of any salt water. My cockpit drains make an easy chore of the excess water.

Since I'm doing it solo it's also handy to have engine stop right there at helm.