MD 2030 Penta Cooling System

Coolant is forced out of overf

Coolant is forced out of overflow but is constantly replaced by sea water. Heat exchanger pressure tested OK. End caps replaced and thoroughly tightened. What can cause this?

"The only place You have them

"The only place You have them 'close' is the heat exchanger. Drain the engine for coolant, put a water hoose on the raw water innlet at the heat exchanger, another at the outlet with a ball valve on, open the valve, apply pressure from the water hose, partly close the ball valve so You have an over pressure. Does Your engine get filled up?"

"Have exactly same program as

"Have exactly same program as described by Andy McCarter.

Morten - if one performs your suggested test and the engine fills up, does that mean there is an abnormal (should not exist) connection between the raw sea water flow pathway and the freshwater/coolant pathway within the heat exchanger itself? or does it mean something else?
If the engine does not fill up, then what does one conclude?
If you have such an abnormal connection the two water flows, what's the solution...new heat exchanger?

Med vanlig hälsning,

Jerry DiBona, gift med en svensk från Göteborg...och kan lite norsk (bodde i Oslo 1979-80, sabbatsår på Ullevaal Sykehus)"

"Jerry:
Fy deg, du har rappet

"Jerry:
Fy deg, du har rappet en annens post!
(Sorry all for the Norwegian)
The leak may be in the exhanger element itself or the seals, very difficult to tell. Sometimes it leaks only one way which makes it a bit difficult to find the exact point of leakage. One way is to 'test' the element separately and have that part eliminated, but be carfull with how much pressure You apply, and do not use air. Another thing is that the element should be heated up to 'operating' temperature which will be close to 85C in case it is a 'thermic' crack."

I tested the heat exchanger us

I tested the heat exchanger using mains water pressure. Then I put in back in the engine and did a stupid thing. I connected the raw water inlet side to a hose and thought to pressure test again in situ. Next thing water is coming out of my air inlet filter. I had to remove injectors and blow water out of the cylinders as a result. Coming back to the primary problem...I think the leak was due to not having the rubber end caps exactly fitted over the ends of the heat exchanger. It's easy to miss and even 1/4 inch out of place will mean you don't have a good seal. It's all back together again now and seems to be working as it should. thanks for the comments and assistance.

That was the reason I wantet t

That was the reason I wantet the valve at the outlet: To prevent You from filling the exhaust system and then the engine through any open exhaust intake valve! Sorry I did not give that extra warning!