Capri 26 - Winterizing the Inboard

[Evan Williams]

From my reading, the inboard Universal has a closed internal cooling system with a heat exchanger using lake water to cool the internal coolant. But, there's a thermostat in that system somewhere?? Anyone know where it is and how it's being used? Does it limit lake water going into the heat exchanger? When winterizing and sucking antifreeze into the cooling input, if I see antifreeze coming out the exhaust, does that mean the thermostat is open and antifreeze has infiltrated the heat exchanger?? Am I totally off base?? TIA

 

[kappykaplan]

You should have a radiator cap, and the thermostat is under the neck - just like on an automobile. The thermostat controls the flow of antifreeze/coolant to the engine. The raw water flow through the heat exchanger is not thermostatically controlled. Welcome to the forum!

 

[Davidasailor26]

What Kappy said. From a winterization standpoint you just need to run antifreeze through the raw water circuit. Suck it in from a bucket with the hose usually attached to the seacock. The antifreeze will go through the heat exchanger and muffler and then out the exhaust.

 

[Stu Jackson]

It would help if you told us what engine you have.

Otherwise, look here:

Engines 101 - The BIGGEST & BEST collection of M25 Series Universal Engine Information on the Internet, plus some M35, too This includes a link to the Critical Upgrades topic which has more engine information please read it too.

Diesel Engine - c34.org

 

[Evan Williams]

Ah...so the thermostat controls the internal cooling system flow to the engine side of the heat exchanger. To winterize, all I need to do is handle the hoses to & from and the lake-water side of the heat exchanger. I don't need to warm the engine (M2-12) to open the thermostat. Much thanks!!