Oil Cooler - Cold to touch? (long)

[Adam]

Well, I've had my 2.7 back on the road for a couple of days and the weather has been pretty cold (last night was 54ºF overnight), so I've had to go on long drives to test out my new Carrera Oil Cooler.

I took my car up into the mountains to really work some heat into it and spent about an hour and a half giving her a workout. When I stopped for fuel, I reached up into the guard (fender) to feel for the cooler. I expected to sear off a few fingertips, but the cooler itself was stone cold. The temp gauge showed approx 85ºC (185ºF) after giving it a hiding in the hills. Just normally driving around, the temps dropped to around 80-82ºC (176-180ºF).

When I got home, I again checked the cooler. It was stone cold, yet the lines leading up to it were pretty damned hot. The stone shield/cover is aluminium and I know that aluminium dissipates heat nicely, but I expected there to be at least a little warmth on the shield or at least the cooler. It was freezing cold.

Is it because the cooler is new and clean, that it's working like this? The cooler in the '89 Cab gets hot. The 2.7 doesn't. Maybe after a few thousand miles worth of road dirt gets stuck in the fins etc, it'll heat up. Tomorrow it's going to be 26ºC/79ºF, so hopefully getting stuck in some traffic or something will get it hot.

I'm not worried, just wondering why it's functioning so well. Does anyone have any ideas about what's going on?

[Adam]

Sorry, I should also clarify...

The (oil line) thermostat was open, because the lines were hot all the way upto where they meet with the cooler. Perhaps, in the cold weather, with an efficient cooler, the thermostat closed itself?

The car is running in an aggressive state of tune (plenty of advance), so I'm at a loss to understand this. I guess I just expected to feel radiated heat from the unit.

[Chuck Moreland]

Try feeling the 36mm tube nuts that thread onto the cooler. The stone guard may be throwing you a curve.

[Adam]

Hi Chuck,

The nuts were hot to touch. I reached up toward the front of the cooler (not easy on a lowered 911 with a chin!) and the front of the cooler was chillin' too. I'm not complaining (far from it ), just perplexed!

[pwd72s]

I'd think if the nuts were hot, oil should be going into the cooler???