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How does the oil cooler system work?

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ecbsykes
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Joined: Sun Mar 08, 2009 3:43 pm
Year and Model: 2000 V70XC
Location: Charleston, SC
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How does the oil cooler system work?

Post by ecbsykes » Tue Jun 21, 2011 9:47 am

I've had this question burning in my mind for a long time, and a recent thread has pushed me to figure it out. Can someone explain the entire system for me (and rest of the forum)?

What I know is this:

-There is the unit that is attached the the oil pan, and the two small hoses that go to it have coolant in them.
-Inside the oil pan are some tubes (not main pickup) that go somewhere containing what? coolant?
-Oil is pumped through two hoses to the radiator to be cooled, these contain oil, not coolant. Is this related to the oil cooler unit (with coolant) on the back of the pan?

Thanks!
Ed Sykes
2000 V70XC - Emerald Green - 249,000 miles

mrscullini
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Year and Model: 05 XC70, 08 XC70
Location: Truckee, CA USA
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Re: How does the oil cooler system work?

Post by mrscullini » Tue Jun 21, 2011 10:25 am

it appears the unit is a small heat exchanger. from what i can tell, oil is pumped through ports that are on the mating surface with the oil pan. see this link,

http://www.partsgeek.com/catalog/2001/v ... ooler.html

i'm hoping this is my problem. sure seems a lot easier to replace this than a head gasket. also, this seems like a more servicable design than the oil cooler integrated into the rad.

jimmy57
Posts: 5384
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Year and Model: 2004 V70R GT, et al
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Re: How does the oil cooler system work?

Post by jimmy57 » Tue Jun 21, 2011 10:58 am

it is a parallel plate cooler. It is configured as though you took a radiator and sealed the finned area where air normally passes and pushed oil through the radiator. Of course, now the radiator coolant absorbs heat instead of giving up heat. The oil from oil pump passes through filter and then goes through oil cooler before returning to go to crank, cams, turbo.
The coolers integrated in tank of radiator work this way too with a little modification. Those have the oil going through a mini radiator that sits in the hot end of radiator. Auto trans cooler gets the cold end.

jblackburn
MVS Moderator
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Year and Model: 1998 S70 T5
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Re: How does the oil cooler system work?

Post by jblackburn » Tue Jun 21, 2011 11:04 am

Do these also have some sort of oil thermostat to control when oil does/doesn't go through the cooler like the 1998-earlier models do?
'98 S70 T5
2012 Chevy Cruze LT 6MT


A learning experience is one of those things that says, "You know that thing you just did? Don't do that."

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fields 100
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Joined: Sat Mar 19, 2011 6:33 am
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Location: illinois

Re: How does the oil cooler system work?

Post by fields 100 » Mon Oct 31, 2011 7:28 pm

jimmy57 wrote:it is a parallel plate cooler. It is configured as though you took a radiator and sealed the finned area where air normally passes and pushed oil through the radiator. Of course, now the radiator coolant absorbs heat instead of giving up heat. The oil from oil pump passes through filter and then goes through oil cooler before returning to go to crank, cams, turbo.
The coolers integrated in tank of radiator work this way too with a little modification. Those have the oil going through a mini radiator that sits in the hot end of radiator. Auto trans cooler gets the cold end.
So, if this is closed, no fins exchanger, the oil, in the beginning of the engine operation, is being warmed up (not cooled) by the coolant which heats up much faster than the engine oil. The thermostat, I believe, is just a plunger and a spring, that allows the oil circulate through the heat exchanger while it is cold and thick, and then, when the oil loses some viscosity during warm up, the plunger closes and there is no more circulation through that heat exchanger in the radiator. I think it makes sense as it keeps condensation from the intercooler down to the minimum during short urban trips in the cool weather.Just my theory.Any opinions?

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