Direction of Coolant Thru Stock "Oil Cooler"
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From: PDX
Direction of Coolant Thru Stock "Oil Cooler"
Recently, I replaced the center cartridge of my turbo with one that has fittings for running coolant through the housing of the cartridge. Initially, I used the same coolant line that fed the stock oil cooler (before I removed the stock oil cooler and installed a remote oil filter and integrated heat exchanger in the upgraded C&R radiator).
That coolant line has two points of entry/exit from the block. One is a nipple fitting located on the passenger side of the block just above and aft of the oil cooler. It is labeled the "oil cooler bypass hose". The other is a tube that runs across the front of the block. It is labeled the "water bypass tube". Both are shown on page 10-3 of the Helm's manual.
The former fitting comes out of the side of the block and there is no way of telling how the coolant flows to (or from) it inside the block. The second fitting (the tube) runs across the face of the block and eventually leads to a fitting that sits near the thermostat (i.e., near where the lower radiator hose returns cooled coolant to the engine).
My question is this: which direction does the coolant flow through this line? Does it go from the side of the block, through the oil cooler bypass hose, through the oil cooler, through the water bypass tube, and into the block near the thermostat? Or does it go in the reverse direction?
I need to know this because it's clear that the heat being pulled off my center cartridge is NOT getting extracted by the radiator but is, instead, being recycled through the engine. Otherwise, there's just no explanation for why I'm running so hot (225-230 degrees) under hard throttle on the track when I've got a massive aftermarket radiator with a 2300 cfm fan. My ECTs now track my EGTs almost exactly.
Looking at the Helm's manual makes it clear that regardless of the direction of coolant flow, the heated coolant is not immediately finding its way back to the radiator. Once I know the direction of the coolant flow, I can fix the problem by routing the return line from the turbo (i.e, the one that contains heated coolant) directly back to the upper radiator hose, thereby avoiding running that hot coolant back through the engine. I
That coolant line has two points of entry/exit from the block. One is a nipple fitting located on the passenger side of the block just above and aft of the oil cooler. It is labeled the "oil cooler bypass hose". The other is a tube that runs across the front of the block. It is labeled the "water bypass tube". Both are shown on page 10-3 of the Helm's manual.
The former fitting comes out of the side of the block and there is no way of telling how the coolant flows to (or from) it inside the block. The second fitting (the tube) runs across the face of the block and eventually leads to a fitting that sits near the thermostat (i.e., near where the lower radiator hose returns cooled coolant to the engine).
My question is this: which direction does the coolant flow through this line? Does it go from the side of the block, through the oil cooler bypass hose, through the oil cooler, through the water bypass tube, and into the block near the thermostat? Or does it go in the reverse direction?
I need to know this because it's clear that the heat being pulled off my center cartridge is NOT getting extracted by the radiator but is, instead, being recycled through the engine. Otherwise, there's just no explanation for why I'm running so hot (225-230 degrees) under hard throttle on the track when I've got a massive aftermarket radiator with a 2300 cfm fan. My ECTs now track my EGTs almost exactly.
Looking at the Helm's manual makes it clear that regardless of the direction of coolant flow, the heated coolant is not immediately finding its way back to the radiator. Once I know the direction of the coolant flow, I can fix the problem by routing the return line from the turbo (i.e, the one that contains heated coolant) directly back to the upper radiator hose, thereby avoiding running that hot coolant back through the engine. I
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From: PDX
Thanks for the post, Alex.
If you look at the Helm's manual, it's clear that the problem will exist in some form regardless of which direction the coolant flows (although it might be worse in one direction than another). Thus, swapping the lines probably won't tell me much about which direction the coolant actually flows.
The issue *IS* relevent for rerouting the return line from the turbo, however. If I don't pull coolant from the pressurized size of the system, there won't be any flow into the turbo housing (but I'll have no way, really, of knowing that, as there's no temperature sensor inside the center cartridge of the turbo). The coolant just won't flow.
As for the diagnosis, I've spent the past month pondering this, with a lot of help from the guys at C&R Radiators, GilbertG, HeCash, TwoHoos, Titanium Dave, and some other folks, and we've pretty much eliminated all the other explanations. I'll spare you the list, but I've done pretty much everything one can do (changed the coolant mix, used the Mugen thermostat, changed my EMS fan settings, etc., etc., etc.). In short, I'm highly confident, but not entirely sure. I won't know until I try it...
CB
If you look at the Helm's manual, it's clear that the problem will exist in some form regardless of which direction the coolant flows (although it might be worse in one direction than another). Thus, swapping the lines probably won't tell me much about which direction the coolant actually flows.
The issue *IS* relevent for rerouting the return line from the turbo, however. If I don't pull coolant from the pressurized size of the system, there won't be any flow into the turbo housing (but I'll have no way, really, of knowing that, as there's no temperature sensor inside the center cartridge of the turbo). The coolant just won't flow.
As for the diagnosis, I've spent the past month pondering this, with a lot of help from the guys at C&R Radiators, GilbertG, HeCash, TwoHoos, Titanium Dave, and some other folks, and we've pretty much eliminated all the other explanations. I'll spare you the list, but I've done pretty much everything one can do (changed the coolant mix, used the Mugen thermostat, changed my EMS fan settings, etc., etc., etc.). In short, I'm highly confident, but not entirely sure. I won't know until I try it...
CB
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From: PDX
Alex,
I've been walking this path for a LONG time. The turbo already has an oil line for lubrication. There's also a water line to cool the housing...
That's the one I'm concerned about now. The oil line works just fine.
CB
I've been walking this path for a LONG time. The turbo already has an oil line for lubrication. There's also a water line to cool the housing...
That's the one I'm concerned about now. The oil line works just fine.CB
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From: Washington State
CB, I've got the same question. I'm running a water cooled turbo and C&R radiator, and think the temps are too high giving the amount of cooling capacity. Since I'm getting ready to pull the engine to replace with a built low compression block, I'll disconnect those two lines and see which one pumps when I crank the engine. It will be a few days before I get around to it though.
