Front oil cooler on late 80's Carrera's; How do you know if it functioning properly?
 

I have been noticing over the last few days that my oil temps are hovering around 210 in light traffic. The weather here has been in the mid 80's and dry. The car is not moving for long at high speeds, so I believe there isn't much air flow over the front cooler. I have generally never seen the temps go over 200 at the track. This has me thinking; how do you test if you front cooler is functioning properly? Should you here a fan noise kick in (I don't)? What temps does the front oil cooler become functional? Does this rely on a relay or a fuse and perhaps this is not working? The car is an 89 with the radiator type cooler and I think a fan housing at the front of it (can't see it). Tips on checking if it is working properly appreciated.

As soon as temp reaches 180+ oil should be flowing to the front cooler, gently touch the oil lines in the fender to feel if they are hot. You also have a fan attached to the front of the cooler but it may not kick on till oil temp reaches 240 (I think) so you may never get to the point where your fan turns on. As long as you are cruising along, air flow should be hitting the cooler allowing it to do its job.

Drive the car around hard on a hot day for a hour or two.

Get out, and grab the cooler oil tubes real hard and don't let go. If you scream and curse me as you smell the odor of burning flesh then it is working fine.

KNS has it right, even with the temps. You can replace the 244 degF activated thermostat on the cooler with a BMW part that activates lower..around 210 or so...IIRC.

- Wil