Raw\Fresh cooling system

[SanJuanDreamer]

As some of you know, a mechanic sank my boat in June, still working the courts.
I plan to get another Carver Mariner 350, but they are few and far between on the west side.
I’m considering purchasing from land locks states the middle.
Problem I’m seeing is most are raw-water cooled, which means I would need to add a fresh-water cooling system. So as I’m on the same page…
Raw = pumping external water through engine. Fresh = pumping antifreeze through engine

Any thing I should consider\watch out for?

[mjk1040]

I don't know about that terminology! Open or Closed cooling is what I would want to see. I think it would be expensive to convert and open cooling system to a closed one. Keep looking you'll find one maybe one even in fresh water too!

[bud37]

Source of the post Any thing I should consider\watch out for?

Good luck on your search, do you mean to watch out for just the cooling design or the boats overall .

My understanding is there are a few conversions out there some better than others, the only thing that would concern me would be putting antifreeze in a system that has just had water in it, anti freeze cleans things.Would it be possible to just go with the raw until you cant any more, considering a used boat already I am sure with a flush system the longevity may be the same.......obviously something to consider I guess.

What you really need out there is a single small diesel with dry stack exhaust and keel cooling.. ...

[Viper]

Source of the post.... So as I’m on the same page…...Raw = pumping external water through engine. Fresh = pumping antifreeze through engine

Correct but technically you're not pumping coolant through the engine, you're circulating the coolant within the engine. The coolant goes through a heat exchanger where raw water draws heat from the coolant in separate chambers.

There are two common types of fresh water or closed cooling systems; block only, and block and exhaust manifolds. Considering raw salt water manifolds should be replaced after 5 years to be proactive, consider finding a vessel that has a fully closed cooling system that includes the manifolds.

There are conversion kits out there to move to closed cooling or you can simply buy all the necessary OEM parts needed to do the job. It's pricey. The caution is that you don't know the internal condition of the block's cooling passages. Even raw water cooled blocks in fresh water lakes rust. The rust scales that break away eventually make their way through the system and out the exhaust. A block that was previously raw water run then converted may eventually pose a problem to the heat exchanger. Having said that, I've seen conversions operate just fine for years. If you go that route, make sure you replace the t-stat with a hotter one if the kit doesn't already come with it. Your engine/s will be happier.

[390Express]

It's not so much closed cooling advice, but:

If you haven't settled with your insurance company/the mechanic, or mechanic's insurance company, you may be able to pull all or most of your current setup off of your boat, and still get full recovery from the ins. co or mechanic's insurance co.

If you still have possession of your boat, and you're working with an insurance co on a settlement, you can likely remove pieces of your cooling system and even your motor without effecting your settlement.

Tell them you're checking for damage to see what it would cost to repair, and when you realize that it would cost too much, (which sounds like it has already been decided) demand full recovery. They won't care that certain parts are missing from an already totaled boat. Or if it's just a manner of removing of parts, add a couple hoses, convert it to a raw water setup, and keep the closed cooling parts.

[SanJuanDreamer]

Bud, Viper, I heard the same thing.
390, The boat is gone and I wouldn't want any parts off of it anyway...it was a mess of battery acid, fuel, oil and salt water soaked...it sank up to the steering wheel