How important is closed cooling in salt??

[s1120]

OK, so to give you a little background...

I have a moring that I keep my boat on in a bay on Cape Cod. I dont use the boat a lot, but it spends a fair amount of time sitting on the water. My last boat, I fear is due for the scrap yard. It had a 3.7L with the closed cooling system, and I have had no issues with that setup at all. Well most non 3.7l boats I am looking at dont have that setup. How important is it to have it in salt water? Should I add it to whatever boat I get, or are there ways to work around it?

Thanks for any help!

 

[mkast]

Re: How important is closed cooling in salt??

Most boats used in salt water are flushed after use.
The more you flush, the better off the boat is, right up to the point you realize, I should get closed system cooling.

 

[mthieme]

Re: How important is closed cooling in salt??

Most boats are not flushed after use in salt water but should be.
A closed cooling system will extend the life of your motor tremendously, paying for itself self times over. I'm on the Chesapeake which only has half the salinity. My setup is fresh water cooled and extends through the manifolds. I'm afraid to check the risers!!!. It's 20 years old and still ticking perfectly. Personally, I would not have a boat in salt water without this. I certainly wouldn't buy one that was in salt water w/o it either.

 

[s1120]

Re: How important is closed cooling in salt??

How big of a job is it to add it?? Any good links or threds on adding it? I am pretty skilled mechanicly, and I am not afread to get my hands dirty.

 

[mthieme]

Re: How important is closed cooling in salt??

There are add-on kits. By the time you get done, they run close to a grand.
They are not hard to install. The heat exchanger gets bolted on the front somewhere and you have to replumb. So a couple of bolts and scores of hose clamps is what you're up against (basically).

 

[Lou C]

Re: How important is closed cooling in salt??

Well, you can run an IO in salt without closed cooling but sooner or later the engine will rust through....manifolds need checking/replacement at 5-7 years...so in a perfect world you'd have a full (engine+manifolds) closed system. My '88 FW with a 4.3 is raw water cooled and it has never been apart, at least the last 8-9 years run in salt. Manifolds changed 3 seasons ago. If I got a new engine, FOR SURE I'd put in closed cooling. If you try to add it to a boat run in salt for more than 100 hrs the rust already there can clog the heat exchanger. If the boat came from a freshwater region you might be able to add FWC after the fact. For me I'll run this one as long as I can and the new motor will be FWC before it leaves the driveway.

I have winterized mine by draining it and then backfilling with the best -100 antifreeze with corrosion inhitors, I think this does help because it keeps out air, and of course rust is really iron oxide (iron needs the oxygen in water and air...to rust....keep out both and you have less rust). In fact I replace the thermo housing in 2003 and I pull it off every year to change the thermo and there is hardly any rust in it, compared to the old one that had a lot of flaking rust....

 

[WizeOne]

Re: How important is closed cooling in salt??

No personal experience here but many will tell you not to add a cooling system to a used salt motor. They say, and it makes sense, that you will constantly plug up the heat exchanger with rust coming out of the block.