Sunrocket24

iTrader: (1)

So I want a crossover (to clean up the front of my engine) but should I have closed cooling? I moved down to salt water this summer. Right now boat has standard Merc open cooling. I live 3 miles from the boat ramp and flush for 15min on the hose when I get home. The only time the boat might sit in the water overnight is for Poker Run For A Cure next year. Is it a big deal if the boat sits in salt water overnight and not flushed? Should I get the closed cooling?
Thanks

mike tkach

iTrader: (3)

if the maority of the time you are boating in salt water i would go with the closed cooling,your engines will thank you.

Sunrocket24

iTrader: (1)

Thank you Mike! I can't wait to move back up north to the fresh water! this salt water stuff sucks a$$!

Vinny P

Forget about the cross over. In salt, it is more important to run closed cooling. Take a look at this picture. It is of a intake manifold from a 575 SCI that I am rebuiulding this winter. It has about 200 hrs of use in salt water, flushed after every use. Both starboard and port intakes look the same. This rebuild, I will be putting closed cooling on both engines.

Sunrocket24

iTrader: (1)

Vinny, My current intake looks like that. I bought it used and it was like that when I got it and I'm replacing it this winter. I thought it was from the salt, the guy I got it from must have run in salt. So now to find a closed cooling set up!

ezstriper

can't run a crossover with a closed system...need the pump to circulate the engine coolant, like Vinny said, salt kills any aluminum parts quick, iron takes longer but does that in in time...

Vinny P

sunrocket,
Dont be too hasty to throw away an expensive intake manifold. The ones from the 575 SCI's I am doing are being repaired. The trick for me will be to fabricate every thing I need to get closed cooling on these engines. There are no pre-made kits for them. If you are interested in taking on this project, I suggest using Monitor Products heat exchangers. They may even have a kit you can use for your engine.

http://www.monitorpro.com/

Sunrocket24

iTrader: (1)

Vinny, I think I will pull the manifold off when I get home and see how bad it is, I was worried about it sealing 3 years ago but I have not had a problem with it yet. Never thought about having it repaired. Thanks for the link! I was also looking at Mr. Cools website, they both make kits for my engine. So i'm thinking it would be best and spend the extra money and get the full kit that does the manifolds also?

tpabayflyer

Another vote here for monitor products.... I live in the Tampa area and went up to brooksville and picked up my kit locally...... Talked to some of the guys there and they said they make 1000 units a month for yanmar diesels..... Among many other OEM applications...... I had to modify my kit a bit as my intake manifold is much taller than stock and had to fab up taller brackets. I rebuilt the 7.4 in my Wellcraft cruiser last year and replaced all the exhaust and heads. Original stuff was 7 years old and corrosion was horrible....... Raw water cooled setup of course but now After I flush I use salt away religiously..... The stuff really works well and after about 75 hours use the manifolds look excellent. It should be mandatory for Any boater using raw water cooling in the ocean to use salt away........ TBF

tpabayflyer

I should clarify that my wellcraft is raw water cooled and my Donzi project wit aluminum heads, intake, and exhaust manifolds has the monitor closed cooling setup......