Retrofitting Mercruiser Closed cooling V8s

tpenfield

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I got the stainless steel elbows on my 1996 engines :thumb:
 

achris

More fish than mountain goat
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I got the stainless steel elbows on my 1996 engines :thumb:

Interestingly, SS elbows were never an option for my 1994 4.3, but due to me being a sneaky bas...d I know they came out on the Magnum 5.7s and the big block engines (hence you have them ;)), and I also knew the standard 5.7 ran the same manifolds as the Magnum, and the SS elbows bolted straight on those. I also knew that the iron elbows on the standard 5.7 were the same as the ones on the 4.3. By simple 'because this...that', I concluded that the SS elbows would fit on my 4.3.... Happy me. :D.... But no SS for my dry-joint MPI. :(

Chris......
 

HT32BSX115

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Dec 8, 2005
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Yeah, Mine is a 97 and a magnet sticks to the risers. They're in good condition however, but having closed cooling, I would really like to have SS risers.........

I guess my other choice would be these from CPPerformance.... and other suppliers....
620-32410.jpg


Bolted to my cast (closed cooled) extensions, they would work good I guess.....problem is, they cost about $1000 :eek:
And they do not eliminate the leak points on the manifolds and extensions.

Dryjoints are the obvious solution to leaks............. Sure wish I could use 496 manifolds and risers......
 
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tank1949

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Apr 4, 2013
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Howdy,

I bought my 1997 Mercruiser 454/Bravo in 2006 to replace the 1987 460 King Kobra in my FourWinns 211 LIberator............... It had 122 NON-salt water hours on it when I installed it........before I put the engine in the boat, I installed a San Juan Engr full system I bought from http://www.oceaneastmarine.com/freshwater.html I still have it. It works fine.

Cheers,

Rick

I went to web site and didn't see kit with additional pump to bolt onto V8 which would pull water from thru-hull fitting. Most here indicate that Alphas need more water if I cool exhaust manifolds too. We have 88 degree water in July-August.
 

HT32BSX115

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Dec 8, 2005
Messages
10,083
I went to web site and didn't see kit with additional pump to bolt onto V8 which would pull water from thru-hull fitting. Most here indicate that Alphas need more water if I cool exhaust manifolds too. We have 88 degree water in July-August.

88 degrees! I want to boat where you boat!

Most of those kit providers do not provide the pump since Mercruiser has an OEM pump available. You didn't indicate what engine you have but since it's an Alpha, I'll assume you have a 350 (or similar) cu-in engine. You would absolutely need to get the Bravo mount and pump for your engine. There's also after market pumps available....... I have a Hardin Marine stainless steel "Bravo" pump on mine.

You would need to install a through-hull water pickup too. And if you're going to replace the engine you would likely replace the manifolds too. If you do, be sure to switch to "Dry-Joint" manifolds. It eliminates the possibility of a riser gasket leak. (since there's NO riser gaskets)
Regards,

Rick
 
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