cooling system help

[almost perfect 2]

I have a westerbeke 10-2, diesel inboard. It is cooled with both fresh water and sea water.
the intake for sea water (thru hull) has a sea cock that can be shut off and another valve above it in the boat with a hose attached that should suck water . when I ran motor with the hose in bucket it did was not pumping water out of the exhaust. Last year while in the water it worked fine with the thru hull suction?
I closed the thru hull valve and opened the one with the hose attached.
did not want to run it for long with no water running out of the back.
can anyone offer any suggestions or help?
Thanks

 

[31seahorse]

Hello almost perfect 2,

Is this the first time you are doing work on your Westerbeke 10-2?

If it is a new experience...... you need to learn how to check/replace the impeller in the sea water pump, and you need to realize that the pump may be airlocked in some way even if the impeller is OK. Put water into the intake hose before you dunk it into the bucket of water. Time to buy/read a repair manual or get a boater friend who is more experienced to help you with this "not too uncommon" problem. Personally, I learned a good deal from friends who were more experienced than I was. Best Wishes

 

[Ron20324]

My first thought would be was the hose in the bucket sitting on the bottom- and stopped up?

 

[Skipper]

was it sucking water out of the bucket? You said not coming out the back but didn't say if it was entering from the bucket.

If no, then might be an air lock. Either make sure the hose is full of water IE: start the siphon 1st, or just put the bucket up higher than the pump, with the hose directly shooting down to the engine's plumbing. I do this by putting the bucket in the cockpit, with the bucket-hose running to the connector on the raw-intake hose.

 

[dparilla]

When was the impeller last changed?

it could be as simple as insufficient water pressure by only have a bucket full of water (it will take longer to prime without that head of pressure.) But, I would check the impeller before going much further. They can freeze up in the off season and break apart when you try to run the engine in the spring.