Oil Cooler = BAD? My results say so!
10-05-2004, 01:35 PM
#1
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Oil Cooler = BAD? My results say so!
Last week my car developed tic tic tic noise that increases proportionally with RPM. I took the car out to Moss to have the noise checked out as well as swap my FMIC for AWE intercoolers. Moss thought the noise sounded like a hydraulic lifter tic. So we changed the oil. When we drained the bucket that the oil was drained into you could see the oil seperating from the other contaminants in the bucket. Most likely fuel and condensation from cold starts. We had a local dealer tech come take a look at the car.
The diagnosis was a bad lifter or possibly a cam chain tensioner caused by contaminated oil.
He saw my oil cooler and asked what my normal operating oil temps were. I told him that since installing the oil cooler I had not seen over 200. The only times my oil would get to 200 is sitting in traffic on 100+ degree days and then on highway trips I never saw over 175. It was determined that my low oil temps were the cause of oil contamination becuase my oil never receached a high enough temp to burn off the contaminants in the oil.
Optimal oil temps under normal driving conditions are 220+ish. You want you oil to get to 220 to burn off the condensation and fuel from cold starts. Normally this is not a problem because the oil gets hot enough to burn the contaminants off through crank case ventalation system and goes out the exhaust. But with the my oil cooler this is not possible as the oil does not reach 220 resulting in nothing be burned off.
BTW: My car is currently being fixed and I had the oil cooler that is available from DUH Engineering on my car which is identical to the one from ACHtuning.
This brings up some questions.
1. What are factory RS4 oil temps with factory RS4 oil cooler?
2. Is the thermostat different or set higher than the one available from ACHtuning and DUH Engineering?
3. If the thermostat is the same. Is the core size to big? Or is the mounting location recieving too much air flow?
4. Is the oil cooler even a good idea at all if your car is anything other than a dedicated track car?
Here is the pic of my oil cooler and location. The little cooler in front is the power steering cooler.
<img src="http://pictureposter.audiworld.com/71856/img_2207.jpg">
The diagnosis was a bad lifter or possibly a cam chain tensioner caused by contaminated oil.
He saw my oil cooler and asked what my normal operating oil temps were. I told him that since installing the oil cooler I had not seen over 200. The only times my oil would get to 200 is sitting in traffic on 100+ degree days and then on highway trips I never saw over 175. It was determined that my low oil temps were the cause of oil contamination becuase my oil never receached a high enough temp to burn off the contaminants in the oil.
Optimal oil temps under normal driving conditions are 220+ish. You want you oil to get to 220 to burn off the condensation and fuel from cold starts. Normally this is not a problem because the oil gets hot enough to burn the contaminants off through crank case ventalation system and goes out the exhaust. But with the my oil cooler this is not possible as the oil does not reach 220 resulting in nothing be burned off.
BTW: My car is currently being fixed and I had the oil cooler that is available from DUH Engineering on my car which is identical to the one from ACHtuning.
This brings up some questions.
1. What are factory RS4 oil temps with factory RS4 oil cooler?
2. Is the thermostat different or set higher than the one available from ACHtuning and DUH Engineering?
3. If the thermostat is the same. Is the core size to big? Or is the mounting location recieving too much air flow?
4. Is the oil cooler even a good idea at all if your car is anything other than a dedicated track car?
Here is the pic of my oil cooler and location. The little cooler in front is the power steering cooler.
<img src="http://pictureposter.audiworld.com/71856/img_2207.jpg">
10-05-2004, 01:49 PM
#7
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Bad idea unless you track the car very often for the reasons you mentioned
and if you run synthetics, you can safely run up to about 275 degrees.
Here's a tip for you all track-goers. Try running without your belly pan, it lowers your oil temp dramatically.
Here's a tip for you all track-goers. Try running without your belly pan, it lowers your oil temp dramatically.
