I have a question on a volvo penta 7.4 engine

[llewis01]

I have question on a 1994 albemarle 265 with a 7.4 engine. My problem is that can not keep antifreeze in the heat exchanger. I have had it tested and passed. Pulled the heads had them redone and shaved and magnafluxed. New exhaust manifold and risers. There is no water in the oil. Just can not figure out where it’s going.
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[alldodge]

Has to be the HE, was it tested fully drained and at least 15 psi?

 

[Lou C]

agreed you need to do a cooling system pressure test and also make sure that combustion gas isn't getting into the antifreeze, this can over-pressurize the system and cause it to lose antifreeze. Cause is usually a leaky head gasket hope it's not that in your case.
in addition to testing the system, make sure that the cap holds pressure and the flanges on the H/E for the cap are holding it tight.
example, leaky head gaskets were common on older Subarus, what would happen is the combustion gas would get into the antifreeze, and cause bubbling and overflow in the coolant recovery tank. the tank would then eventually overflow. We had one that did this twice and we never had AF in the oil.

 

[llewis01]

the HE was tested at a radiator shop. new head gaskets were installed along magnafluxed the heads

 

[Lou C]

I would do 2 tests:
pressure test with HE installed, you can have leaks from other places, hoses, front water pump, core plugs, etc
combustion gas test, to see if combustion gas is getting into the AF. even though the HGs were replaced, unless the cyl head bolt holes were carefully cleaned out, head bolts were either cleaned or replaced, and torque specs carefully followed, HGs can still leak.
No AF in the motor oil? does it run at normal temp?

 

[llewis01]

hrad bolts replaced and torqued to specs. I will get a pressure tester when it gets a little warmer.

 

[Scott Danforth]

You have a leak somewhere

So, oil cooler, HX, or a leak in the exhaust as VP only does half systems