Was told that if my engines had any time in salt that converting to closed loop was no go, the salt in the iron would come out and turn the antifreeze/coolant into goo.

Anyone have experience with old iron and new conversion. Even with new block and intake, old heads would be too much salt iron I was told.

Sounds like BS.

I'd be sure to give the engine a good fresh water flush before adding the anti-freeze just to be safe though

Kinda sounded like BS also, but it was a supplier of High HP fresh water cooling systems that told me no go, wouldn't sell it for my application (550 HP 540 CI). So I went Raw Water Cooled.

If you have rust in the engines and you swap over what will often times happen is the rust will clog up the exchanger. It can require you to flush the exchanger out a number of times before it will start to run correctly

Jon