When a heat exchanger goes bad

[matta0413]

My neighbor at the marina has 8.1 Crusaders and the expansion bottle on his port engine has been filling up and pressure has been pushing the coolant out. He is thinking he may have a bad heat exchanger and is taking in sea water. Is that common? When my heat exchanger went bad I was loosing coolant out the exhaust. Can it work the other way?

 

[diver_dave]

Trying to remember what happened when mine leaked. I believe both happen, but at different times. Simply a function of relative pressures. Before the engine builds coolant pressure, the salt will enter coolant. If/when the coolant pressure builds, coolant will escape. And, at shutdown, coolant will be lost.

On my VD xmission, ATF went away, no salt in the tranny.

 

[RicardoMarine]

He can pick up hydrocarbon test strips from the auto parts store. These can be dipped into the E/G coolant (E/G = ethylene glycol) .
The test strips will indicate if there are hydrocarbons leaking into the E/G. (i.e., combustion by-products leaking from a cylinder)

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