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Mark IV to Gen V Crusader

F

fibersport

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I have a Mark IV Chevy 454 in a 1984 Century with a cracked block. I have a line on a Gen V 454 that is in a truck as a replacement. I know most of the differences between the engines: oiling system, heads, crank etc. The question I have is regarding the cooling system. Since the Gen V system is different, can I simply use the original cooling system or will I have to look at upgrading it to match the newer style?
 
The Gen V was only installed in trucks and it is not a tall block, the Mark IV came in a tall block and I think the Gen VI did as well. I'm not looking for an upgrade, just a block with no cracks in it. I know the flow direction was changed but what I don't know is how that might affect the Crusader cooling system from the older engine.
 
I think most of the bolt ons would support the conversion except for the thermostat housing and heat exchanger....for those, I'd be incline to think you have to get the GenV/VI versions.....

There may be a way to reroute the flow to make use of the old heat exchanger but it sure isn't obvious to me....
 
My Mark IV is raw water cooled so no heat exchanger, it does have the engine oil and trans fluid coolers though. I still need to find out the differences of the flow.
 
RWC may be easier....the u cooler is ok as is.

The big difference is the coolant flow is internal to the engine....some of what I remember was the GenV/VI flow is 'parallel' vs Mark IV's 'serial' flow.

The coolant inlet to the block is still via the circulating pump....the outlet is where the uncertainty occurs.....

looking at the RWC diagram, it looks like there is no difference between the Mark IV and the GenV - so I'd say shouldn't be a problem.
 
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Thanks, I was going to start looking at part numbers and other diagrams I could dig up. I have a book at work that covers the engine differences, I'll have to check into it and see if they cover anything.
 
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