Conversion from raw to fresh water cooling?

[Boat bums]

Greetings all,

Long time former Hatteras owner looking to own 38-40 Carver. In my search I have found at bunch with raw water cooling. That won't work for me as I am going to spend 50% of my time in salt water and be there for 4-6 months. Does Carver or any of the engine folks sell a conversion kit?

TIA
Russ Appleton
Manning, SC

[buster53]

I don’t have the specifics, but yes, you can convert those engines. I’m sure a quick google search will come up with whatever pieces/parts you will need and there are probably a couple dozen videos on YouTube showing the process. Just punch in, convert RWC to FWC.
From what I have read, for a number of years, do not convert RWC engines that are used in salt water as the salt has literally engrained itself into the engine cooling passageways and will cause problems when mixed with anti freeze.

[Cooler]

Yes, make sure you are starting with a freshwater boat. Carver is no longer in business. You may want to contact engine manufacturer also. Good luck, I know conversions have been done to boats located up here and moved to salt water. er

[dlldxb]

What engine manufacturer? I used the Crusader part catalog to identify replacement parts on my 5.7MPI It was a conversion when i moved from lake to south florida. Converted before it went into salt. Just make sure you know if full or half, manifolds are fresh or salt. This will come into play when you replace risers later and will or won't need block off plates.

[buster53]

dlldxb has a point. If you’re going to the trouble and expense to convert engines into fresh water cooling, make sure you go with a full system as opposed to a half system. With a full system, chances are real good you will never have to replace your manifolds.

[MyPleasure]

I just converted the Volvo 740b gas engines in our 1992 Carver 36 aft cabin to fresh water cooled. Not an easy task with Volvo marinized engines, as with everything Volvo, nothing is easy or cheap. I can only get the 1/2 system on the Volvo’s because Volvo used a very unusual thermostat housing that they had for a full closed cooling system, is no longer available. The hoses to the exhaust manifolds go to and from the thermostat housing.
Looking at the heat exchangers that I purchased, there may be heat exchangers that have extra hose connections that run from the fresh water side of the heat exchanger to and from the exhaust manifolds similar to the Mercruiser setup, but I’m not positive that it would work.
I really don’t want to buy another set of heat exchangers, but I may have to go that route to make it a complete closed cooling.