Originally Posted by doug86
He is wrong.
"Just an added note: The engine technician told me that a heat exchanger leak would cause salt water in the coolant since the pressure on the salt water side is higher than the fresh water side."
I know from personal experience that raw water can enter the heat exchanger system through a leak, but if it did it would over flow the expansion tank...not the problem this owner has experienced.
On our Pathfinder engine there is one special hard rubber boot caps on each end of the heat exchanger (each boot cap takes two hose clamps), designed to separate the raw water side from the engine coolant side. Once my engine over flowed at the expansion tank, and it wasn't from over heating
. I flushed the coolant, installed another refurbished tube stack in the heat exchanger (a back up), installed new boot caps and hose clamps, and refilled with new coolant mixture...I had no more over filling of the expansion tank. I took the replaced tube stack along with an extra head
exchanger I have to a radiator shop I use for testing, and the replaced tube stack checked out good with no leaks
. The problem was with the hose clamps not clamping around the boot caps good enough, letting raw water enter into the coolant side of the system. So it is possible for raw water to enter the coolant side, and I check the hose clamps periodically for tightness.