Closed cooling on fresh water with aluminum heads?
SubscribeAfter all this time waiting, my new 502 engine build is finally running.
New GM block
Promaxx aluminum heads
BMP aluminum intake manifold (brass lined marine version)
New oil cooler
CMI E top (fusion) exhaust
Boat will be run in only fresh water. And will need to be winterized yearly.
New block, so scale/rust is not an issue. Intake manifold is brass lined, so that's good. I'm wondering about the untreated heads and unlike metals.
Is it worth the cost and hassle to go closed cooling? And if so, would you do half or full?
https://www.cpperformance.com/p-7394...per-brass.aspx
https://www.cpperformance.com/p-7979...per-brass.aspx
To be honest, I really want the serpentine belt conversion (currently have V) and cost of closed cooling is nearly the same.
https://www.cpperformance.com/p-1266...ting-pump.aspx
New GM block
Promaxx aluminum heads
BMP aluminum intake manifold (brass lined marine version)
New oil cooler
CMI E top (fusion) exhaust
Boat will be run in only fresh water. And will need to be winterized yearly.
New block, so scale/rust is not an issue. Intake manifold is brass lined, so that's good. I'm wondering about the untreated heads and unlike metals.
Is it worth the cost and hassle to go closed cooling? And if so, would you do half or full?
https://www.cpperformance.com/p-7394...per-brass.aspx
https://www.cpperformance.com/p-7979...per-brass.aspx
To be honest, I really want the serpentine belt conversion (currently have V) and cost of closed cooling is nearly the same.
https://www.cpperformance.com/p-1266...ting-pump.aspx
I’m repetitive here, but CC and Daytona Sensor ignition system are the two best investments I’ve ever made to my boat……
The CP kit fits both std deck and tall deck. I just kept my V-Belt setup - it’s foolproof and easy and those belts last decades…….

The CP kit fits both std deck and tall deck. I just kept my V-Belt setup - it’s foolproof and easy and those belts last decades…….

JaniH
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Quote:
New GM block
Promaxx aluminum heads
BMP aluminum intake manifold (brass lined marine version)
New oil cooler
CMI E top (fusion) exhaust
Boat will be run in only fresh water. And will need to be winterized yearly.
New block, so scale/rust is not an issue. Intake manifold is brass lined, so that's good. I'm wondering about the untreated heads and unlike metals.
Is it worth the cost and hassle to go closed cooling? And if so, would you do half or full?
https://www.cpperformance.com/p-7394...per-brass.aspx
https://www.cpperformance.com/p-7979...per-brass.aspx
To be honest, I really want the serpentine belt conversion (currently have V) and cost of closed cooling is nearly the same.
https://www.cpperformance.com/p-1266...ting-pump.aspx
With your cmi stainless steel headers, i would buy the half system. I highly recomend the closed cooling where ever you are boating.Originally Posted by xlint89
After all this time waiting, my new 502 engine build is finally running.New GM block
Promaxx aluminum heads
BMP aluminum intake manifold (brass lined marine version)
New oil cooler
CMI E top (fusion) exhaust
Boat will be run in only fresh water. And will need to be winterized yearly.
New block, so scale/rust is not an issue. Intake manifold is brass lined, so that's good. I'm wondering about the untreated heads and unlike metals.
Is it worth the cost and hassle to go closed cooling? And if so, would you do half or full?
https://www.cpperformance.com/p-7394...per-brass.aspx
https://www.cpperformance.com/p-7979...per-brass.aspx
To be honest, I really want the serpentine belt conversion (currently have V) and cost of closed cooling is nearly the same.
https://www.cpperformance.com/p-1266...ting-pump.aspx
scippy
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I run EFI (as&m) tall deck chevy 572's w/alum manifolds and haven't learned yet to convert to closed cool ....salt alone has ruined 2 pairs of Imco "power flow plus:" manifolds & risers ...been talkin
for years but no action sorry to say!
for years but no action sorry to say!
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for years but no action sorry to say!
cmon Scippy - you would seriously sleep so much better. It honestly feels so good. I’m not exaggerating - I just felt this complete sense of relief once installed. Originally Posted by scippy
I run EFI (as&m) tall deck chevy 572's w/alum manifolds and haven't learned yet to convert to closed cool ....salt alone has ruined 2 pairs of Imco "power flow plus:" manifolds & risers ...been talkinfor years but no action sorry to say!
Probably already winter in NY - pull the trigger and get started….
Tartilla
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The full systems are more complex. They need coolant flow though the exh manifolds before thermostat opening.Originally Posted by JaniH
With your cmi stainless steel headers, i would buy the half system. I highly recomend the closed cooling where ever you are boating.
+extra plumbing.
Fresh water cooling half system would be my go-to for fresh water boating.
F-2 Speedy
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Salt water for sure....fresh water spend the coin somewhere else.
scippy
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Probably already winter in NY - pull the trigger and get started….
if I would've have put aside half the $$$ I spent on beefing up my tow truck which pulls my boat CC would have been done a long time ago...my priorities really suck!...but, this winter or bust!!Originally Posted by seafordguy
cmon Scippy - you would seriously sleep so much better. It honestly feels so good. I’m not exaggerating - I just felt this complete sense of relief once installed.Probably already winter in NY - pull the trigger and get started….
Quote:
The CP kit fits both std deck and tall deck. I just kept my V-Belt setup - it’s foolproof and easy and those belts last decades…….
I've seen your recommendation for both and have been thinking about them. Did not realize your polished pullies were still Vee belt. I just assumed it was serpentine.Originally Posted by seafordguy
I’m repetitive here, but CC and Daytona Sensor ignition system are the two best investments I’ve ever made to my boat……The CP kit fits both std deck and tall deck. I just kept my V-Belt setup - it’s foolproof and easy and those belts last decades…….
Part of my reason for wanting the serpentine conversion was for the ability to spin a higher output alternator. They recommend a serpentine or a dual vee for 150 amp alternator.



