fresh water/closed cooling system

Commissionpoint · Post by **Commissionpoint** » Wed Feb 15, 2012 5:22 pm

Well if you think about a car with a radiator its up front where fresh air from moving down the road can pass through it and cool off the fluid inside. This effect is enhanced by fans like when you are in traffic or moving slow.

In your bilge, there really is no source of a large volume of moving air to pass through the radiator. Even with a fan you are just pushing hot engine compartment air through the fins. The water you have the boat in is a much better source for cooling the hot fluid in your closed cooling system which is why we have these setups and not the radiator system you see on cars.

jefflaw35 · Post by **jefflaw35** » Wed Feb 15, 2012 5:50 pm

Wow I can't be leave after 20 years of being an auto collison tech I just had to be told that,,,, um I don't know what I was thinking

Stripermann2 · Post by **Stripermann2** » Wed Feb 15, 2012 6:23 pm

jefflaw35 wrote:so all this leads me to wander why i cant drop an old ford radiator with and electric fan down there, think its possible?

You can...

jefflaw35 · Post by **jefflaw35** » Wed Feb 15, 2012 6:48 pm

I'm thinking if I ran extra duck vents off the side I could get some heat relief but like it was said already thats a lot of hot stale air down there and the fans just are not gonna be enuf

Big D · Post by **Big D** » Wed Feb 15, 2012 8:13 pm

Jeff, it's likely that your engine is seized due to water getting into the cylinders from bad exhaust manifolds or elbows. Unless you have closed cooled exhaust logs, there will be raw water running through them then overboard with the exhaust. When these fail, water will enter the exhaust side in the log and enter the cylinders through the exhaust ports. It is suggested not to expect more than a 5 year life span from exhaust manifolds running with salt water. If you're getting a long block, I would consider new manifolds and elbows because of this to prevent killing your new block.

prowlersfish · Post by **prowlersfish** » Wed Feb 15, 2012 8:21 pm

jefflaw35 wrote:so all this leads me to wander why i cant drop an old ford radiator with and electric fan down there, think its possible?

To put it simple no . the heat has to go somewhere . no where near the air flow needed in engine room .

You need the raw water to cool the exhaust anyway

jefflaw35 · Post by **jefflaw35** » Wed Feb 15, 2012 9:00 pm

Big D wrote:Jeff, it's likely that your engine is seized due to water getting into the cylinders from bad exhaust manifolds or elbows. Unless you have closed cooled exhaust logs, there will be raw water running through them then overboard with the exhaust. When these fail, water will enter the exhaust side in the log and enter the cylinders through the exhaust ports. It is suggested not to expect more than a 5 year life span from exhaust manifolds running with salt water. If you're getting a long block, I would consider new manifolds and elbows because of this to prevent killing your new block.

I agree.

foofer b · Post by **foofer b** » Thu Feb 16, 2012 9:01 pm