V6 coolant weirdness!

[f85gtron]

While tearing down a 2.8, I drained coolant from the pipes and it was red (because of the every-compatible fluid I filled up with last) and the coolant in the block after pulling the heads is green!  That tells me that the coolant doesn't flow properly through the system. Now, I've never had any overheating issues and am surprised at this finding. I never liked the way the coolant gets pulled into the block on the same end that it gets pushed out on the v6. My hypothesis is that to flip the lower intake around and push coolant out the other end (transmission side) and use a 4cyl hose to facilitate the change. Other than the obvious issues that would arise (idle bypass tube, thermostat housing interference, minor wiring rerouting), what would be the problem with this that I'm not seeing?  In other words, there must be some fault with this thinking because the engineers would have solved this issue before or during production, right?!
Ron

[Raydar]

Is your engine all original?
I noticed that, when I was building my 3.4, the holes in the head gaskets were very small. Seems like they would not provide optimum flow, but they may be designed to better distribute the coolant.
Aside from that, most of the heat is generated in the heads and the upper part of the block. anyway.

But that IS strange. Not what I would have expected, either.

[Fierofool]

All v engines are set up that way.  In at the bottom of the engine and out at the top of the same end.  There might be some internal design that makes it cool equally. 

[f85gtron]

Apparently, it's a non-issue, or less my car would've overheated a long time ago....but for arguments' sake? 
That makes sense that the heads take on most the heat because of the compression and combustion that happens up there. I'm confident that they're getting proper flow because they're not warped and both the ecm and the coolant guage are in agreement.  It just seems contrary to expectations that all the engine would not have consistent coolant flow through the block too.  My mind just got blown.

[Fierofool]

The water being heated around the cylinders does come up through the heads and out the filler neck.  It would take a bit of re-plumbing for fuel and vacuum lines, but because the manifolds are symmetrical to the heads, it could probably be done.  The 4-cylinders do have a flow-thru design with the pump being on the passenger end and the outlet on the driver's end.  I don't know if the Duke was set up that way in the front engine, rear wheel drive cars, or not.  Both V6 and 4's use the same temp sensor and run at the same temp range, so there really may not be much gain.  If it did run cooler, the ECM would need to be re-programmed, too, I would think, to keep the air/fuel mixture correct.

[f85gtron]

I'm thinking the t stat would keep the temp up in the correct range.

[Fierofool]

You're right.  It would.  It would still run at the same temp and still flow through the same plumbing.  I just replaced the rad on my truck and the first coolant out of the drain was rust colored, like it wasn't circulating through the bottom tank.  My trans cooler is located inside the bottom tank.

The only thing eliminated would be the v6 crossover pipe.  Might improve flow.  Was the only color variant just in the heads with everything else being red?

[f85gtron]

The variant was the cooling system was red (orange) heads, pipes, radiator, hoses, and only the coolant remaining in the block water jackets was green.

[Fierofool]

In my best Foghorn Leghorn imitation---Boy!  I say Boy!  Sumpin' ain't right.   

[pgackerman]

I am neither a chemist or Sherlock Holmes.  However, I can sometimes follow clues.

Clue 1, f85gtron's engine did not turn into molten metal driving from the CSRA to Toccoa and back.
Conclusion: his cooling system works.
Clue 2, oil and water don't mix.  Neither does salt and fresh water.  Why should two different kinds of coolant?
Clue 3, His car has been sitting since his clutch problems started about a month ago.

Conclusion, the two coolants separated. 

This theory can be tested by placing both coolants in the same clear plastic bottle.  Shake it up and see if they separate.  Better yet, find some old vision-ware, bring the contents to a low simmer, turn off the heat, and see if they divide.  Don't forget to stir while simmering to simulate track conditions. 

[TopNotch]

Clue 2, oil and water don't mix.  Neither does salt and fresh water.  Why should two different kinds of coolant?

And neither does red and green antifreeze, if the red is what I think it is. Danger, Will Robinson!

[Fierofool]

The DexCool is supposed to be a long life antifreeze, but there have been some reports that it tends to gel if it isn't drained and replaced every year or so.  Our Grand Prix had to have the heater core power flushed when it stopped putting out much heat.  After that, it got good old green Prestone.  I run that stuff year after year after year without draining.  As long as it tests to below zero, I only replenish it as needed. 

[GTRS Fiero]

What was the red coolant?

[scottb]

Dexcool..... another wonderful idea brought to you by General Motors

[GTRS Fiero]

I thought it was something that is compatible with all coolants.