The 24 Hours of Lemons Forums → Lemons Tech → Oil Cooler question: What about using radiator ATF feature?
The answer is probably simple. but thought I'd ask:
Radiators for automatic application have a section used for transmission fluid to flow through it and shed some heat. What if such a radiator is used in a manual transmission car and instead of leaving the trans cooler portion unused, why not plumb the engine oil through the trans fluid routing?
It probably has something to do with pressure and temperature...
Just curious.
Neither pressure or temp are of issue, inadequate flow volume is the going to be the problem.
Yea, I thought the issue I'd seen previously is that it's too restrictive and you'd be losing a lot of pressure.
General rule of thumb that I've seen is that you want oil cooler lines to be equivalent to -10 AN line or larger in order to get proper flow. The A/T cooling lines I've seen are significantly smaller.
Any value in trying to make a manual transmission cooler out of it?
Hmmm. Looking at this
https://wiki.anton-paar.com/en/engine-oil/
https://wiki.anton-paar.com/en/automati … fluid-atf/
shows that, yea, ATF has significantly less kinematic viscosity (whatever THAT is) than engine oil at 100 C. I'm going to guess that equates to how well it would move through passages
I'd do it, but have a bypass line in parallel so the oil going through the cooler doesn't become a pressure drop.
You could have a line from the oil pan, a small external pump, and a line back to the oil pan, and then you're just cooling oil in the reservoir of the pan.
I'd do it, but have a bypass line in parallel so the oil going through the cooler doesn't become a pressure drop.
You could have a line from the oil pan, a small external pump, and a line back to the oil pan, and then you're just cooling oil in the reservoir of the pan.
This should work but it does add extra parts that can fail and won't do that much for cooling as it only cools "some" oil, not all.
A stacked plate oil cooler with either -10 or -12 fittings and lines is the way to go and plumb it so that all the oil goes through the cooler either before or after the oil filter. With stock oil pumps you won't see much of a pressure drop.
I've been racing cars for over 30 years and all of my cars have had oil coolers and I've had no issues with restriction or oil pressure loss using this size oil lines and coolers.
There are "oil to water" oil coolers, some come stock and there are a few aftermarket units as well but unless you have a "big" radiator all you're doing is adding heat to the coolant that still has to be gotten rid of.
Any value in trying to make a manual transmission cooler out of it?
Absolutely ! With a suitable pump and gauge to monitor.
Also can be used to cool power steering fluid.
Just remember that anything you plumb through there will likely wind up the same temp as your coolant. If you're trying to cool certain fluids below that point, better to just get a dedicated cooler for that fluid.
FWIW, I just wrapped my lips around the port for the ATF and blew and, well, lots of restriction in there. Not sure I'd use it for engine oil. At least not this particular radiator.
FWIW, I just wrapped my lips around the port for the ATF and blew and, well, lots of restriction in there. Not sure I'd use it for engine oil. At least not this particular radiator.
Pretty sure this is exactly how NASCAR engineers test oil cooler flow rates.
If you REALLY want to get all lemonsy with this...
Dumpster-dive yourself a fuel lift pump from a 90s'ish diesel pickup truck and use that as an independent re-circulation pump with pickup and return ports directly welded into the oil pan. You can now use any type of cooler you want; ATF cooler, power steering cooler, AC condenser cooler, etc...This will obviously put zero strain on your existing oiling system. Additionally, you can very easily modulate the oil temperature by manually switching the pump on / off based on oil temps.
chaase wrote:Any value in trying to make a manual transmission cooler out of it?
Absolutely ! With a suitable pump and gauge to monitor.
Also can be used to cool power steering fluid.
What is this power steering you speak of?
What is this power steering you speak of?
That empty reservoir towards the front of the engine with a pulley with no belt on it and a couple of stubby pieces of cut-off rubber hose sticking out of it is called "power steering". Not sure what it does or why they call it that, but that's what I heard.
chaase wrote:What is this power steering you speak of?
That empty reservoir towards the front of the engine with a pulley with no belt on it and a couple of stubby pieces of cut-off rubber hose sticking out of it is called "power steering". Not sure what it does or why they call it that, but that's what I heard.
This quote needs to go somewhere and be immortalized.
Just remember that anything you plumb through there will likely wind up the same temp as your coolant. If you're trying to cool certain fluids below that point, better to just get a dedicated cooler for that fluid.
Not only will the coolant keep the oil temperature up but the oil will raise the temperature of the coolant making it warmer also. Separating it allows each to cool as efficiently as possible.
TheEngineer wrote:Just remember that anything you plumb through there will likely wind up the same temp as your coolant. If you're trying to cool certain fluids below that point, better to just get a dedicated cooler for that fluid.
Not only will the coolant keep the oil temperature up .
This is a thing? Living where it is hot all the time it seems oil is ALWAYS 30deg over coolant (no matter the car or if it is even a racecar)
BoB wrote:TheEngineer wrote:Just remember that anything you plumb through there will likely wind up the same temp as your coolant. If you're trying to cool certain fluids below that point, better to just get a dedicated cooler for that fluid.
Not only will the coolant keep the oil temperature up .
This is a thing? Living where it is hot all the time it seems oil is ALWAYS 30deg over coolant (no matter the car or if it is even a racecar)
Yes, it's a thing. Often times coolant/oil exchangers are used to help bring the oil up to temp faster when the car is turned on. Then once everything is at temp, they take some of the heat out of the oil. They aren't sized to take all of it out, but some is removed and added to the coolant system load. But bringing the oil up to temp is important in regions where it actually gets cold.
Team Infinniti wrote:BoB wrote:Not only will the coolant keep the oil temperature up .
This is a thing? Living where it is hot all the time it seems oil is ALWAYS 30deg over coolant (no matter the car or if it is even a racecar)
Yes, it's a thing. Often times coolant/oil exchangers are used to help bring the oil up to temp faster when the car is turned on. Then once everything is at temp, they take some of the heat out of the oil. They aren't sized to take all of it out, but some is removed and added to the coolant system load. But bringing the oil up to temp is important in regions where it actually gets cold.
Thanks!
But I would love to add, WARMING the oil should be of no concern past getting the car to grid and letting it idle or taking it easy during the first laps, I couldn't see over cooling the oil during a race where WOT is frequent.
I may be wrong...
Thanks!
But I would love to add, WARMING the oil should be of no concern past getting the car to grid and letting it idle or taking it easy during the first laps, I couldn't see over cooling the oil during a race where WOT is frequent.
I may be wrong...
Yeah its more of a thing for street use in a cold climate, can't see it ever being needed for Lemons.
Thanks!
But I would love to add, WARMING the oil should be of no concern past getting the car to grid and letting it idle or taking it easy during the first laps, I couldn't see over cooling the oil during a race where WOT is frequent.
I may be wrong...
You are not wrong. The oil being too cold is really not an issue for Lemons races.
FWIW, years ago we did dyno testing with dry sump sprint car engines. Was kind of surprised to see about a 10% HP loss when the oil was merely warm vs at operating temp
FWIW, years ago we did dyno testing with dry sump sprint car engines. Was kind of surprised to see about a 10% HP loss when the oil was merely warm vs at operating temp
Absolutely, when I was drag racing regularly, I had to make sure I warmed the car up sufficiently before the run.
The 24 Hours of Lemons Forums → Lemons Tech → Oil Cooler question: What about using radiator ATF feature?