FWC 350 manifold question

O

offbase

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Was wondering why it is necessary to run the coolant hoses through the manifold on a FWC engine? Any thoughts?
 
Bondo

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Re: FWC 350 manifold question

offbase said:
Was wondering why it is necessary to run the coolant hoses through the manifold on a FWC engine? Any thoughts?
Click to expand...

Ayuh,.... Welcome Aboard,...

Whether included in the freshwater side, or cooled by the raw water side,...
The manifolds are still Water Cooled....

which hoses ya talkin' about, 'n is yer system a full system or not,..??
 
O

offbase

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Re: FWC 350 manifold question

Hi and thanks for the welcome. I have Marine Power 350 blocks that are closed system with heat exchanger and raw water cooled. I guess my question is why does the closed system run into and out of the manifolds? Car motors do not use the coolant to run through manifolds.
 
Bondo

Bondo

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Re: FWC 350 manifold question

offbase said:
Hi and thanks for the welcome. I have Marine Power 350 blocks that are closed system with heat exchanger and raw water cooled. I guess my question is why does the closed system run into and out of the manifolds? Car motors do not use the coolant to run through manifolds.
Click to expand...

Ayuh,... Car manifolds have millions of cfms of air flowing through the motor box...

Boat motors run in a somewhat sealed box...
in close quarters to extremely flammable stuff...
 
O

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Re: FWC 350 manifold question

So, the closed system goes through the manifold and cools the manifold down?
 
J

John_S

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Re: FWC 350 manifold question

If your kit says to install one, best to do so. I recently looked at mercruisers closed cooling and saw that they run a hose from water circ pump to intake manifold. In the context of why I was looking at, it was for another discussion on coolant flow prior to thermostat opening.
See: http://forums.iboats.com/showthread.php?t=520775 post #12. Not sure it is the info you want or if that is the actual reason it is installed.
 
Lou C

Lou C

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Re: FWC 350 manifold question

The manifolds get hot enough, that you need the antifreeze that flows through them, to flow to the heat exchanger, to release the heat it picks up flowing through the manifold. The heat of the exhaust flowing out the exhaust ports heats up that cast iron pretty fast. Yes car manifolds are not water cooled but a boat application is totally different, closed engine box with no to little air flow around it...
 
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