Jay Gratton

I agree with changing the oil before you put it at the proper time and then change the filter from time to time just to be safe. I like to change the filter when the car is cold and the oil has drained out of the filter. It makes a lot less mess! - Jay

der Mond

I drove in winter conditions down to -10 a couple winters, if you have further questions. My throttle was sticky when it got cold and I believe it was the cruise control cable, which I would recommend disconnecting for winter. I used Mobil1 0W-40 oil in good faith. I could hear a grunt when the engine caught which I took to be the oil pressure bypass doing its job. Upon reading later posts on Pelican by a shop owner who had measured wear on valve guides on various engines using the same oil consistently over time, I reached the conclusion that it is unsafe in the generation 3.2 that we have to use anything but an oil with "50" in its viscosity specs, not even Mobil1 0W-40. I would recommend Mobil1 15W-50 for your winter driving. You will become expert in the various combinations of HVAC settings in short order. Sometimes only "all on" (fresh air, heat, auxilary blowers, A/C all on full blast) is the only thing that will clear all the windows. Handling wise, we have already had a tire discussion; the main thing is never, never "lift" throttle in a curve, keep it exactly steady if possible, take it out of gear to brake if there is any question how slippery the road is. Easy on the throttle, finesse, finesse. Otherwise the car absolutely loves to go straight and rear-wheel traction is pretty good, especially if you have limited-slip

Mike Murphy

The reason why I initially asked is because my engine warms up to about the middle between the 1st and 2nd line. This equates to about 167 degrees. Tech expert Steve said that this is not uncommon with air-cooled engines: "The engine temperature seems to reflect the outside temperature a lot more than the water-cooled engines." Just wondering what your oil temperature is when it's below 30 degrees outside...

gunlover05

I don't have a numbered temp gauge, but I drove my 85 to work today and it was @ 28 degrees F....my oil temp needle barely gets out of the bottom thick solid indication mark while driving...

Mike Murphy

I don't have a numbered gauge either, but if you take a flashlight, you can probably see to the far left of the gauge the numbers printed in Celsius. See attachment (which was modified to include Fahrenheit). Good to know that when cold, these engines, well, run cold!

theiceman

I definitely think the cold normal and too hot are open to interpretation. Here in Canada my car has maybe once gone into the 194 range. My car runs in the 160 -180 range and I consider that "normal " for my car and climate.

der Mond

Normal "warmed up" winter operation was fairly consistent...the orange needle was just slightly above the thick white block at the bottom, so, say, 160 degress or so as iceman sayeth.

Mike Murphy

The internal thermostat open the valve to the oil cooler at 80C (176F), so it makes sense that the engine doesn't get above that temperature in cold temperatures. I wonder why the thermostats don't open close to 190, especially the fan on the external cooler at 244F. Much to wide a range I think.

ron mcatee

murphy, that's why i put the lower temp thermoswitch in my 88 Carrera. It now comes on automatically at 210 F.

Mike Murphy

That's what I'll do come summer. Thanks

der Mond

Spider, tell me about the lower temp thermoswitch..

ron mcatee

Der mond, here is what I did on my 88 Carrera.

1988 Carrera oil cooler 244 F thermo-switch replacement with a lower temp one

The factory thermo-switch mounted on the Carrera oil cooler on my 88 Carrera was rated at 244 F. I obtained the info on putting a lower temp unit in from another Rennlister a year or so ago. It was about using a BMW radiator auxiliary fan switch that worked very well for him. I bought one from Pelican and put it in the car. The factory wiring harness has a single wire with a round spade type connector going to the single pole thermo-switch. I had two options (1) cut the factory wiring and solder in a flat spade connector, or (2) make a small 3-inch wire coupler with a round spade on one end and a flat spade connector on the other end. I chose option 2 so I didn’t mess up the factory wiring. I put a double layer of shrink wrap over the connection to make it rigid so I wouldn’t have to go back in there for a while. The BMW auxiliary fan switch is a two prong, Red Top, 99 degree Celsius switch (equates to 210.8 F) made by FAE, P/N 61-31-1-364-273-M323 and costs $13.75 from Pelican. Your local BMW dealer may have one, but cost may be higher. It is from a 3 series E30 1983-1991.

You have to remove the flex lines attached to the oil cooler and the hard lines. Be careful when loosening the mounting bolts on the oil cooler. There is a lot of oil in there and any movement will cause it to spill on you. Once you have enough oil out of the cooler to remove it, carefully lower the cooler to the ground and dump the rest of the oil out of the cooler into a drain pan. Then remove the factory switch from the cooler. You may opt to cut the factory wire and install a flat spade female connector because the BMW part has two male connectors on it (see below). Install the BMW switch with a new gasket and tighten. It doesn’t matter which male connector you plug the wire onto. You then need to make a ground wire that will connect to the other male spade on the switch. I used brown wire just like the factory so there is no doubt as to what it is for. I made my ground wire about 8” long and put a female connector on one end and a connector with an eyelet on the other end. How long you make the ground wire is up to you. Make sure the eyelet is big enough to have a 10mm head bolt go through it, because on top of the oil cooler beside the new switch there is a 10mm head bolt you can use to mount the ground wire. Once all the electrical is done, remount the cooler, reinstall the flex lines, and start the car and let it come up to operating temperature. Once the hard lines get hot, check for any leaks at the flex and hard lines. If you need to change the flex lines, now’s the time to do it. If no leaks are detected, let the engine run and monitor the heat gauge in the car. Make note of the temperature when the oil cooler fan motor comes on. Depending on gauge calibrations, it should come on at about 210-215 F. I wanted my hook-up to be automatic so that’s why I did mine this way. Hope this helps explain what I did. Let me know if you need more.

der Mond

Spider,
Wow, thanks!!!
I looked up all the parts and got photos and see what you're talking about. I would have to decide if I would need that mod. In Fairbanks in the summer it doesn't get that hot, but I could see that it would be a great mod for San Antonio. My wife and I tentatively plan one road trip to the Grand Canyon and back, but that would be in spring or fall so we wouldn't run into that much heat on the highway. I only had the auxiliary oil cooler come on a few times, when idling in city traffic while driving the car back from Chicago in July 2004. Otherwise my engine runs within primary oil cooler limits. But thanks anyway, your directions are easy to follow and I hope someone needs this info now. Is 244 degrees F. occasionally that much of a problem?

Mike Murphy

230 is warm, 240 is hot, 250 is too damn hot. Occasionally, no, but I don't want my car running that hot. The warmest my car ever got was about 235(stuck in traffic), so I plan on doing the mod.

ron mcatee

der mond, it has been suggested for a long time that keeping temps below 220-230 F provides longevity for an engine. When I found out how high that theroswitch went (244 F), that was my decider to put in the lower temp one. A fellow Rennlister provided the basic info I passed to you and murphy. Whether operated automatically or via a switch under the dash, you need this fix if you live in the lower 48 states.

40 years in PCA and counting.