Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

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Don S

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

No you can't.
First, there isn't enough air flow to cool the radiator, second, the exhaust is way too hot for inside an enclosed engine compartment.
 

haulnazz15

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

You cannot use an automotive radiator in a boat because there is no airflow to make it function. If you want closed cooling, get a closed cooling system with a marine heat exchanger. Why do you need the closed cooling system?
 

cr2k

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

Even if you did manage to make it work you still need water to cool the exhaust or burn out your manifolds and hoses.
 

Don S

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

On that old of an engine, you don't even want to try to convert over to fresh water cooling. Chances are the tubes would clog up with all the rust built up by years of use. The manufactures recommend you install the fresh water cooling system within 125 hours or one year. That 888 is a long way past that.
Just stick with the raw water cooling.
 
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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

actually might already have one... Smells like antifreeze in the cap..

06052012160.jpg

06052012161.jpg
 

haulnazz15

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

Yes, you already have one. That is one rough-looking rig you got there!
 

Don S

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

actually might already have one... Smells like antifreeze in the cap..
Just remember, you need all those hoses, and the thermostat housing, and block off gaskets under the risers.
 

sethjon

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

has anybody done this? I want to do a 100% closed cooling system on my boat.

Nobody in their right mind. Is this a trick question?
 
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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

i'm new... I know hot rods, not boats.. So no its not a trick question... It's called learning.
 
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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

its a project for sure.. 800$ for boat n trailer. Guy needed it gone off his fathers land and had no where for it.
 
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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

06032012155.jpg

here she is.. 22' sangster craft
 

QC

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

Cool looking ride, Ace. Ask questions as you are, but definitely leave the automotive stuff behind. Many things are different, and little is the same except most of the long block, and not all of that. Good luck. Check out our restoration section as well. Looks like you'll need to spend some time there. Same advice, not all is the same ;)
 

spdracr39

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Re: Can I? automotive radiator cooling system on my 188hp 302 mercruiser?

Looks to have good potential. Could be a nice rig.
 

NORDICRAIDER91

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has anybody done this? I want to do a 100% closed cooling system on my boat.
absolutely 100% can. I done it on both my 1979 cobia sportster and my 1978 glastron 178ssv. all you have to do is cap off your exhaust to the outdrive, get rid of the engine cover, use a regular car exhaust manifold or headers and run your exhaust over the transom. lot easier if its a v8 or v6 but 4 & 6 cyl is doable I done my glasstron through the transom. rest is just building brackets to support the radiator and building a screen over the front of the radiator. i used expanded metal and also built a expanded metal deck over the engine compartment it gets plenty of airflow. all you need is a 2 row 19x 21 radiator for a racecar and whatever electric or mechanical fan you choose.
if you want a through hull exhaust get 2 3 inch header collectors black or chrome your choice with a 2 inch outlet. drill a 3 inch hole at the top of the transom. bolt your collectors together with gaskets one inside the hull and one outside the hull. measure the distance from where each collector starts to taper. cut a piece of 3" exhaust tubing to that length and weld to the inside of the first collector. make sure it bottoms out in the collector. next take a piece of 2" OD exhaust tubing and cut it to where it sticks out about 2" on each side of the collectors. before you bolt the other half on pack as much loose strand fiberglass as you can in between the two walls of the collectors. essentially you're building a double wall to keep heat out of the transom. bolt together the collectors and weld the 2" sections and your done. if you want to dress up the outside you can get a stainless steel 3" collector and slip it over the collector on the outside of the transom. inside the boat just run 2" flexible exhaust tubing and your muffler of choice.
 

Bondo

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absolutely 100% can. I done it on both my 1979 cobia sportster and my 1978 glastron 178ssv. all you have to do is cap off your exhaust to the outdrive, get rid of the engine cover, use a regular car exhaust manifold or headers and run your exhaust over the transom. lot easier if its a v8 or v6 but 4 & 6 cyl is doable I done my glasstron through the transom. rest is just building brackets to support the radiator and building a screen over the front of the radiator. i used expanded metal and also built a expanded metal deck over the engine compartment it gets plenty of airflow. all you need is a 2 row 19x 21 radiator for a racecar and whatever electric or mechanical fan you choose.
if you want a through hull exhaust get 2 3 inch header collectors black or chrome your choice with a 2 inch outlet. drill a 3 inch hole at the top of the transom. bolt your collectors together with gaskets one inside the hull and one outside the hull. measure the distance from where each collector starts to taper. cut a piece of 3" exhaust tubing to that length and weld to the inside of the first collector. make sure it bottoms out in the collector. next take a piece of 2" OD exhaust tubing and cut it to where it sticks out about 2" on each side of the collectors. before you bolt the other half on pack as much loose strand fiberglass as you can in between the two walls of the collectors. essentially you're building a double wall to keep heat out of the transom. bolt together the collectors and weld the 2" sections and your done. if you want to dress up the outside you can get a stainless steel 3" collector and slip it over the collector on the outside of the transom. inside the boat just run 2" flexible exhaust tubing and your muffler of choice.
Ayuh,.... Welcome Aboard,.... Please read, 'n follow our posting rules, 'n guidelines,.....
That includes not postin' in threads older than 90 days, unless it's yer own thread,....

This, ^^^^^, should Not be attempted, by Anybody, as it can, 'n will lead to a massive nasty on-board fire, with the potential to Kill people,......
 
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