raw to closed cooling system conversion

F

fibersport

Petty Officer 3rd Class
Joined
Jul 18, 2010
Messages
94
Has anyone converted their Mercruiser raw water cooled system to a closed or fresh water system? In looking at some coolant flow diagrams, it looks like some different hoses and a heat exchager/expansion tank are all that's needed.
 
H

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: raw to closed cooling system conversion

Howdy,

It's absolutely "possible". I did it with my 1997 454 in 2005 before I installed it when it had about 120 hours of fresh water use (no salt).

Most people will advise against it if the engine has been used in salt water for more than a year or about 100 hrs.

I bought the San Juan Engr "kit" from http://www.oceaneastmarine.com/

Regards,


Rick
 
S

Speakrdude

Ensign
Joined
Feb 25, 2004
Messages
942
Re: raw to closed cooling system conversion

Do it to just about every boat I restore/resell. Either half cooled or full. Ask away. Easy kits available.
 
achris

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: raw to closed cooling system conversion

I did it on my in-line 6 (MCM165) many years ago. And later on my new 1994 engine straight out of the box.... Quite simple, yes a few different hoses, and other bits and pieces, and a hotter thermostat.... Didn't do it on 2006 engine because Merc Australia charge $4,000 for the kit and another few hundred for the belt driven pump!

Chris......
 
S

scoflaw

Ensign
Joined
Jun 2, 2010
Messages
962
Re: raw to closed cooling system conversion

Later fuel injected motors with ECM.s need a different ECM, that's why the $4000 quote.
 
achris

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: raw to closed cooling system conversion

scoflaw said:
Later fuel injected motors with ECM.s need a different ECM, that's why the $4000 quote.
Click to expand...

That $4K included the return of the old ECM! THAT is why I think it's a rip-off.

JMHO.... (and why I buy my parts from the US now.)
 
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