Stuck Cooler on Yanmar 3JH4

[Maxs]

Hi, one of the o rings that goes on the manifold/ heat exchanger caps failed. This o ring separates fresh from saltwater. Short story, saltwater got into the freshwater system, and now, the heat exchanger is stuck an won't come out of the manifold.
Has anyone experienced this before?? I've been spraying WD40, but nothing.
I'm really close to take out the manifold and bring it to a shop. Any thoughts??????

[SeaKing]

did you take both end caps off and try to tap it out from "behind"

[Maxs]

Seaking, I did tapped it very gentile, of course. Don't want to damage it, but didn't move. I did wanted to do it harder, but since that cooler is kind of sealed, if I screw it, it will be impossible to repair and is expensive to replace. I have been advised to use Kroll to dissolve salt deposits, but is not available here in Costa Rica .....

[SailorHarry]

Try to dissolve the corrosion with vinegar--it works wonders on aluminum. soak some cloths with vinegar and keep the area saturated for a day or two then take a soft wooden block or rubber mallet and persuade the tube bundle to come out. Good luck.

[Maxs]

Harry, I took the manifold off the engine a few days ago, so I'm going to give it a try with white vinegar for a few days. I can be able to plug the inlet and outlet and fill it up completely....

[Maxs]

Just wanted to let you know that lots of heat and a hydraulic press was needed in order to take out the cooler. Filled it with white vinegar and left it in there for a few days, but nothing...the salt deposits holding it in place were too much. We needed torch in order to heat up the assembly... There was a broken oring in one of the caps and let salt water made it's way to the fresh water system, and caused the dissimilar metals to seize. Fresh water pump was also removed for rebuilt. Fortunately, cooler came out with no harm!