From a risk factor perspective (freezing) you are low so I don't know what would be the compelling event that would drive you to closed cooling. My 280 had the single which was closed and in Oregon we do have lots of freezing weather - closed cooling on a year round cruiser is the only way to go. I suggest your cost to benefit ratio compels you to leave well enough alone. My 2 cents.

mb

 

Rigg.... are you referring to the benefits of closed versus raw water cooling in the salt water? It simply does not freeze in our areas of CA..... so I would not think that would be the reason.

I would think that given you will be on a trailer like I am it would be very easy to flush the motors, genset, and A/C, Heat systems. Using muffs for the engines, a plunger type inboard flushing attachment for the genset (which is closed cooling) and the A/C pickups.... is pretty easy to do. We do not pull from salt water like you would in Newport... but I always like to give everything a thourough flushing after I return home. :smt001

I hope that helps. I myself have never owned a closed cooled boat.... so maybe the folks more familiar with it can chime in with additional benefits.

 

The primary advantage of closed cooling is the protection from the corrosive effects of salt water. If you religiously flush after every trip to salt water, corrosion shouldn't be much of a problem. But flushing isn't always convenient and that's when the salt water becomes problematic. Our 1996 250 Sun Dancer is closed cooled and runs in salt water but is docked in fresh. We just had the risers pulled at 300 hours to check for problems and there were none. The other advantage to closed cooling I've been told is that your engine runs at a more consistent temperature (165-170)and that is supposed to be good for the long term health of the motor. Personally, I just feel better knowing our boat is running on fresh water and antifreeze instead of salt water.

chazaroo

 

I'm definitely not worried about freezing, it's just the piece of mind knowing that salt water isn't touching the internal parts of the engine. I realize that the longest it will be sitting in salt water would possibly be a week and then put back on it's trailer and flushed out.

I'm only interested in buying a fresh water 280. And then I think for each engine, the closed cooling kit is $900 and I figure I could do the install myself. $2k investment for piece of mind and possibly a higher resale value for a future owner that feels better about buying a fresh water cooled boat over a non-fresh water cooled for a boat that was run in the ocean.

Just some thoughts.

 

I think it's a wise investment. :thumbsup: I know I sleep better knowing the salt isn't destroying my engine. :smt015

chazaroo

 

I added a full closed cooling system to my 502. It's just basic engine plumbing, but it can be difficult if the access to the front of the motors is tight (shouldn't be on a 280). Even occassional running in salt with good flushing will still significantly shorten the life of your recirculating water pump and headers.

BTW Rigg315, I'd shop the price on the kits. You should be able to find them for V-6's for closer to 6 - 700 bucks.

 

I installed a closed system on my 7.4L engine in my 270. Really not much to it, except I did use some hoses from Napa that were a better fit than provided in the kit.

The engine warm up is now very much better than before. The engine never runs cold like it used to. I do boat in water that is sometimes less than 45 degrees, so that did tend to prevent the engine warming before, unless on plane. I also did it because I was going to spend a week in salt water.

I don't have any comment on cost-benefit. For me, that did not apply. For me, running the engine cold was just the wrong thing to do, and I felt the same about running salt water through it. Obviously many other people feel differently about it. But I just did it, and would to it again. It was only around $600-$700, as I recall, so not a big issue.

I would not claim that an add-on fresh water cooling system increases the value of the boat to a new owner. He has to believe that it improves the real operation of the boat, was properly designed and installed (as well as a factory unit maybe), and will not fail on the water and thus be a problem source instead of a solution. Manufacturers spend a lot of effort making sure all the parts of a product, be it car, boat, or whatever, work well together. Somehow I learned that over the years. Modify any part, and you may be defeating what they designed.

But it's my boat, and I changed mine anyway. That's my 2 cents worth.

 

Adding closed cooling isn't as simple as is obvious. (Which is why buyers may not think it was a good idea.) The questions:
1. Where will the raw water come from - through the sterndrive or a thru-hull. Is the sterndrive water supply sufficient.
2. Will you be adding a raw water pump? (The engine pump no longer will pump raw water). Is there also a pump in the sterndrive?
3. How much of the engine will be cooled by fresh water? Exhaust manifolds? What changes are needed there.
4. Do you need a thermostat change?
5. Do you need an engine computer change?

 

another factor: simple aftermarket kits will cool only the engine block with fresh water. a more complex system will also divert coolant/fresh water to the exhaust manifolds. this would require replacement of the manifolds (i think?). since it is the manifolds that are a weak link in the system (with regards to the ravages of salt water), i dont think the more simplex closed cooling system is worth it. if you plan on trailering the boat, i'd flush it out when you get home and brag about that at resale time.

 

You can use the same manifolds with a full closed cooling system. The sea pump with Bravo drives will pump the raw water side of a closed system. The Alpha's require the addition of a belt driven pump and preferably a thru-hull feed. Finally, the themostat does need to be changed.