Closed Cooling System Question

[Weist_7469]

Im new to the boating world and just had a few questions about a Closed Cooling System. I like to run my boat in the bay / ocean and was considering installing a closed cooling system. Does the closed cooling system basically run antifreeze / colant through the block instead of the sea water? Will it still work if I had a captains call system on my boat?

Thanks
Drew

 

[Bondo]

Re: Closed Cooling System Question

Im new to the boating world and just had a few questions about a Closed Cooling System. I like to run my boat in the bay / ocean and was considering installing a closed cooling system. Does the closed cooling system basically run antifreeze / colant through the block instead of the sea water? Will it still work if I had a captains call system on my boat?

Thanks
Drew

Ayuh,... Welcome Aboard,.... That would be a Yes, 'n sure why not,...

What's yer motor, 'n drive,..??

How old,..?? always in the brine,..??

 

[Weist_7469]

Re: Closed Cooling System Question

2005 Chaparral 256 SSI
8.1GXi Volvo Penta Duo Prop

Does the raw water still come into the exhaust manifolds and risers?

 

[Bondo]

Re: Closed Cooling System Question

2005 Chaparral 256 SSI
8.1GXi Volvo Penta Duo Prop

Does the raw water still come into the exhaust manifolds and risers?

Ayuh,... It can be done with, or without the manifolds, the risers are Always the raw water outlet,....

Yer motor is t old to convert Now,....

Wait til it needs a long block replacement,...

 

[alldodge]

Re: Closed Cooling System Question

For salt water closed cooling is the way to go. Raw water will still be pumped through the exhaust currently. It will also go through the heat exchanger you would install. Captains call will work as before, no difference as Bond-o previously mentioned

 

[tpenfield]

Re: Closed Cooling System Question

You can install either the 'half' system or the 'full' system. The difference being the 'Full' includes the exhaust manifolds (but not the riser/elbows). So, one less thing to replace periodically.

SeaKamp and SJE (San Juan Engineering) are the popular brands of aftermarket systems.

I put the 'full' systems on my Mercruiser 7.4 MPI engines last fall, as my 'new' boat was going from fresh water to salt water.. So far, so good.

 

[Scott Danforth]

Re: Closed Cooling System Question

I installed a HX large enough for a full system, although only plumbed as a half system. Motor was fresh water only prior. However yours has been in salt water for a bit, the damage is already Don. Wait until you change the long block and manifolds

 

[Volphin]

Re: Closed Cooling System Question

I went with a SeaKamp. Nice little system. But you have been running in salt so long, rust has built up in your engine, and it will dislodge... then the antifreeze will carry it to the heat exchanger where it will plug up the tubes causing an overheating issue. Merc says if you are going to do a freshwater system for a boat used in salt or brackish water it has to be within the first 125 hours of use or the first year, whichever comes first. The only other option is to wait until winter, pull the engine, strip it, have the block, heads & manis tanked and cleaned and reassemble. And that's a lot of work for a motor that is just fine now. So go boating and have fun! One day your engine will let you know it's time for a rebuild and then go with the freshwater system.