Cooling systems

[immortality]

This makes for interesting reading.

http://www.pirate4x4.com/tech/billavista/Cooling/

[psyolent]

my 4AGE also ran the same type of setup. tstat in the lower hose.
not a fan of the cheaper pressed steel water pumps. rather search for the older style types with the cast impellors. when i was chasing the overheating issues with the 304 in the hilux one of the things mentioned over on aussiev8 was shying away from the pressed steel type and sticking with cast.
seen too many of the pressed steel ones rotting away ; agree with what commonut said though ; if good coolant changes etc it shouldn't rust out though.

[MAGP]

I've been thinking about this a bit since you started this thread so I'll post what I'm thinking and see what everyone thinks.

Holden V8 and reverse flow cooling? The Gen 2 Chev redesigned the cooling system to force the coolant to flow through the heads first then down through the block. At the very least GM redesigned the block and the water pump. The water pump had, for each bank, an inlet and outlet port. Cooled water flowed through the top port and hot water through the bottom port.

My thoughts are would it make a difference if an EWP was fitted in the bottom hose but facing in the opposite direction pulling water from the block into the bottom of the radiator so it flows up the radiator out the top hose into the thermostat housing through the heads down the cylinders and out the now empty water pump housing. Doing this would, in theory, completely reverse coolant flow. My question is would it work as it, in theory, should and would it help with things like detonation?

[Charlescrown]

I have replaced lots of water pumps over the years and these days you never see any problem with the impeller or even the pump if the correct coolant and ratio has been used. I think the cast impeller is really an old idea where it will probably last longer if coolant isn't used. I had a Chrysler that was overheating and after a bit of diagnosis we pulled off the pump. Cast impeller. The impeller had almost completely gone having been eaten away by corrosion and cavitation. You could see big scallops cut out of the housing from cavitation. I kept it for 30 years showing students.

[psyolent]

interesting CC
so material of the pump becomes largely irrelevant then. its all in the coolant changes/keep up...

MAGP......you can also get reverse flow water pumps too...

[immortality]

I've been thinking about this a bit since you started this thread so I'll post what I'm thinking and see what everyone thinks.

Holden V8 and reverse flow cooling? The Gen 2 Chev redesigned the cooling system to force the coolant to flow through the heads first then down through the block. At the very least GM redesigned the block and the water pump. The water pump had, for each bank, an inlet and outlet port. Cooled water flowed through the top port and hot water through the bottom port.

My thoughts are would it make a difference if an EWP was fitted in the bottom hose but facing in the opposite direction pulling water from the block into the bottom of the radiator so it flows up the radiator out the top hose into the thermostat housing through the heads down the cylinders and out the now empty water pump housing. Doing this would, in theory, completely reverse coolant flow. My question is would it work as it, in theory, should and would it help with things like detonation?

I think the whole point of having the thermostat in the lower hose is to better regulate the engine temps. basically the thermostat controls how much cold coolant from the radiator mixes with the hot coolant circulating withing the engine to regulate the temps rather then just having cold coolant entering the block slowly flowing through the engine and then exiting the top.

[immortality]

I have replaced lots of water pumps over the years and these days you never see any problem with the impeller or even the pump if the correct coolant and ratio has been used. I think the cast impeller is really an old idea where it will probably last longer if coolant isn't used. I had a Chrysler that was overheating and after a bit of diagnosis we pulled off the pump. Cast impeller. The impeller had almost completely gone having been eaten away by corrosion and cavitation. You could see big scallops cut out of the housing from cavitation. I kept it for 30 years showing students.

Yes corrosion been one issue but how about flow?

I've seen a few large industrial pumps and fairly sure they still have large cast impellers.

From a total design point of view a well shaped impeller will move the fluid better than a poorly shaped one. Most now WP's have small flat steel blades where the older cast impellers have a much longer, curved blade which in my opinion will move fluid better.

IF what I'm been told elsewhere, flow is king and primary concern to getting the coolant system to perform better.

[MAGP]

MAGP......you can also get reverse flow water pumps too...

I didn't know that, who sells them? Are they for marine applications or something like that?

I think the whole point of having the thermostat in the lower hose is to better regulate the engine temps. basically the thermostat controls how much cold coolant from the radiator mixes with the hot coolant circulating withing the engine to regulate the temps rather then just having cold coolant entering the block slowly flowing through the engine and then exiting the top.

I know the point of the thermostat however GM went reverse flow cooling with the early 90s LT1 and then the LS. I was wondering if there would be any benefit to the venerable Holden V8 if it was reverse flow cooled. The thermostat (EWP in this case) would still function as a thermostat so it would still control the temp but the cooler water would enter the heads first instead of the block.

[MAGP]

IF what I'm been told elsewhere, flow is king and primary concern to getting the coolant system to perform better.

Flow is king but the flow has to be controlled so heat can be removed, you can have to much flow.

[immortality]

IF what I'm been told elsewhere, flow is king and primary concern to getting the coolant system to perform better.

Flow is king but the flow has to be controlled so heat can be removed, you can have to much flow.

Apparently not or so I'm told.