FWC or closed cooling?

johndoe

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I read most of the previous posts about fwc and closed cooling systems... When a dealer states that the boat (engine) is FWC, does this mean it is a closed system... (I am looking at 2005, 2006 boats)<br /> How can I tell the difference and what is the cost to insure that it is a closed water cooling system?<br /><br />thanks
 

Don S

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Re: FWC or closed cooling?

Yes, it's the same thing.<br />If it has a heat exchanger with antifreeze in it, then it's a closed system.<br />There are several types, are you looking at Volvo or Mercruiser. OEM or aftermarket system.
 

johndoe

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Re: FWC or closed cooling?

Mercruiser... Searay, Regal... 350's<br />Will be using in Saltwater and want to add heat is its not already on it...<br /><br />Also, where can I find info on all the abbreviations listed with engines... <br /><br />I see this:<br />350 MPI Bravo III MCM<br />350 Magnum MPI Horizon Bravo III MCM<br />350 Magnum MPI Bravo III MCM<br /><br />I know that MPI=Multi Port Injection..?<br /><br />Thanks Don.
 

rodbolt

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Re: FWC or closed cooling?

if you decide then ask for full closed cooling and stainless steel risers, the risers are very expensive up front but dont go bad wich may add reliability and resale at the back.<br />the MCM indicates its a strn drive MIE is inboard, the bravo indicates what model 1,2 or 3. and the rest are various HP models and options.<br /> I cant remember the option package difference but I think all of the magnum and horizons are MPI now. the options are mostly bolt ons.
 

Don S

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Re: FWC or closed cooling?

Do SS risers even exist on the new "Dry Joint" type exhaust system?
 

johndoe

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Re: FWC or closed cooling?

SS risers... wow! never even thought about that.<br />What kind of dollars are we talkin for that?
 

rodbolt

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Re: FWC or closed cooling?

last set I bought were about 500 each and were made by predator I think. I am not sure of the SS riser selections from mercrusier but I understand they have a few.<br /> I have a cousin I set up with a 454 MIE in the mid 90's with full closed cooling and cast stainless risers and its gone over 12,000 hours but the rest of the maint is intense but he is anal about doing it so it lasts.<br />but the return has been limited down time and its still fishing and crabbing 7 days a week for 9-10 months of the year. it goes down for maint a day or two periodically and once or twice due to bolt on issues but so far no mechanical issues.<br /> I have other realatives that leave at 7:30 and are back by 11 with the first beer opened by 11:10 and do absolutly no maint until it quits, they repower every 3 years or so.<br />and usually fight a week or so down time every year waiting for parts and repairs.
 

johndoe

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Re: FWC or closed cooling?

I've seen both. I am anal about keeping things clean, tight, and dry... I do my own maint, but with newer computerized engines and control modules it becomes more expensive to own the tools and testers... still cheaper than a mecahanic over the long haul. My father built large custom yachts for 42 years, and I kinda grew up in the shop and around these things. They are a whole different level of maintenance than a 24 foot cruiser. Seems there was always something being done to certain boats. Mostly, these were anal owners with too much money... but the upkeep on a large yacht is substantial.<br /><br />My goal is to properly maintain my boat and make it last as long as I do... <br /><br />If I were to weigh the cost of stainless risers on a mercruiser 350, vs flushing standard risers (steel?) every time and doing everything you can to preserve the life of your engine (both engines)... in salt water, I guess stainless is worth it... 1k + or - ...
 

johndoe

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Re: FWC or closed cooling?

So, how is a 350 engine converted to have closed cooling? is there no impeller in the outdrive, or is it just a matter of running the engine water hoses through a radiator/exchanger..? I see heater kits, but I have never seen a closed cooling kit...?
 

rodbolt

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Re: FWC or closed cooling?

the heatexcanger is a liquid to liquid version, some are a double pass setup, yes there is still a seawater pump system to provide cooling water to the heat exchanger then the waste seawater is passed through the risers for exhaust cooling.<br /> the dry stack has eliminated a lot of leakage issues and I dont know if anyone is making SS risers for them yet.<br />most folks here that can afford a large boat dont care if it lasts 5 years because they dont intend to keep it over 3, by the 3rd year its tax write off is negligable so its on to the next one.<br /><br /> I gotta agree with ya on the yachts, I quit working on most anything over 35'. but I had one customer that when he took delivery of a yacht would place the order for the next as most have a 2 year lead time.
 

Olds Eddie

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Re: FWC or closed cooling?

I have the IMCO risers for Merc manifolds on my new re-power and I love them. I don't have to flush after saltwater and with the 6" rise I don't worry about reversion or static line problems. I had a bung welded on so I could drain them so they don't freeze up. Good quality stuff.
 

johndoe

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Re: FWC or closed cooling?

What exactly is a dry stack...and how does this help or hurt?
 

Don S

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Re: FWC or closed cooling?

It's not "Dry Stack", it's called "Dry Joint" . It's a new concept by Merc to eliminate the problem of the thin wall between the water and the exhaust that goes bad in older manifolds and risers. They also have gaskets designed to prevent a lot of the low rpm water injestion common in the newer Vortec engines. From my experience, there are VERY FEW here that even knows what they are and how they work, or even knew there was a difference.<br />From what little I have seen of them, it seems like a great idea, and will probably save a lot of engines from hydroloc and water on the pistons.
 
D

DJ

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Re: FWC or closed cooling?

There is no replacement for closed cooling. <br /><br />It is the closest thing to an automotive application that the engine was designed to run in. Marine engines (modern-automotive based) were never designed to run at 160-180 degrees. 200+ is far more forgiving, on the engine-believe or not.<br /><br />It's no different than putting a 160 degree thermostat in your 2005 Chevy/Ford/Dodge pickup. Doing so, in your truck, sends your engine managemnent system into constant state of confusion. Thus it reverts back to its programmed "limp mode". That reverts to lots of fuel used with NO performance boost. The OEM engineers are smarter than the hacks selling so called "performance" parts. Again, believe it, or not.<br /><br />A dry stack is just that. Dry exhaust, NOT water cooled. Dry stacks/exhaust REQUIRE lots of open area, for cooling, with NOTHING flamable in close proximaty.
 
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