closed verses partial closed cooling system

[inlet]

I am thinking about converting to a fully closed cooling system on a pair of mercruiser 350's through velvet drives.<br /> http://www.marinemechanic.com/New-Folder2/v8-cool-flow-clsd.htm <br />Is there a downside. I have read some concerns about the heat exchanger possibly being unable to take the extra heat load. Any thoughts?<br />Why aren't all salt water boats plumbed this way?

 

[bob58]

Re: closed verses partial closed cooling system

I have twin 350 mercruisers with velvet drive transmissions and fresh water cooling. Overheating has never been an issue.<br />The only problem is after several years the exhaust risers get a little caked up but can be cleaned and are easily removed.<br />Zincs should be maintenanced regularly to avoid failure of the engine and transmission coolers from electrolysis.<br />Some other advantages are:<br />not having to drain the block for winter<br />protecting the engine from raw water corrosion.<br />the cooling system remains as clean as your cars does.<br />can install red dot heaters for warming cabin area without condensation from fuel oils or NG heaters steaming up the windows.<br />and on and on .......

 

[Walt T]

Re: closed verses partial closed cooling system

If this is a saltwater boat that has been in salt water more than a year, it's kind of like closing the barn door after the horses got out to install a closed system. If you only boat in freshwater, you probably should save your money for gas. Otherwise there is certainly no harm in installing other than to your wallet. A closed system will enhance your boats resale value.

 

[rodbolt]

Re: closed verses partial closed cooling system

hello<br /> I service many mercruisers both stern drive and inboards with full closed cooling. the only advice I will give you is make sure the package you buy is intended for closed cooling and rebuild the water pump yearly. if this is done correctly the full cooling is far superior but does add some stress to the<br /> heat exchanger.<br /> good luck and keep posting

 

[navigator336]

Re: closed verses partial closed cooling system

Being on the west coast of Canada, the ocean temp on a summer day will be what, 60 degrees F? If you were in Florida, the exchanger might be challenged a little. I'm in So. California, have fully closed cooled engines (350 Indmar's), and they run nice all the time. Our water temp ranges from 52 to maybe 72 during an El Nino year. Indmar uses Orca fresh water cooling systems from Seattle. It kind of sounds like you already have partial closed systems though and just want to add the manifolds to the loop.

 

[inlet]

Re: closed verses partial closed cooling system

navigator336 <br /><br />That is correct. Looks simple enough. But don't want to solve one headache and create two more. Manifolds are good, plan on changing risers, install blocking gasket and replumb. It's only in the thinking about it stage at the moment, waiting for someone to tell me why its not as easy and as sensible as it seems.

 

[Lark40]

Re: closed verses partial closed cooling system

Point of Clarification, please.<br /><br />I'm confused about the difference between partial and fully closed cooling. Don't all of these systems pump raw water into the risers? Wouldn't they therefore all be "partial"?<br /><br />Can someone tell me precisely what the difference is?

 

[Bondo]

Re: closed verses partial closed cooling system

A Partial System Dumps the Raw Water into the Manifolds.......<br />A Full System Dumps the Raw Water into the Risers.....

 

[Lark40]

Re: closed verses partial closed cooling system

Excellent. Thanks, Bondo.