engine cooling

If anyone out there would be able to offer me some advice for the cooling system on my boat. At this stage i have a heat exchanger from engine coolant to sea water and oil cooler separate coolers. Is this the best way to go as it is a trailer boat 25feet and has a 454 mercruiser fitted. I do realise the corrosion issue, with running salt water through the engine block, but at most is would sit in the water for 3 days at a time, engine is alwaysed flushed after use. Any advice would be greatly appreciated.
thanks arnold.

 

"I do realise the corrosion issue, with running salt water through the engine block, but at most is would sit in the water for 3 days at a time,

Perhaps not,

The problem is salts come out of solution and plug the inside passages of the engine at only 140F or so.

The concept of the heat exchanger systems is to have the engine cooling water at 180F , and the heat exchanger large enough to not operate over 140F. The condensed salts do NOT flush away.

If course heat exchangers don't work "perfectly" so there easy to disassemble and clean.

Far easier to purchase a couple of gaskets than a new block.

Advice, Fresh water cooling is worth the effort.

FF

 

And a heat exchanger might not cost that mutch. You could probartly get one for free at a junkyard. They are wildly used in industry and marine so it should not be a huge problem finding one.