Do i *Need* a switch for a cooler fan?
 

Ok, got my Carerra oil cooler installed in my 1980 911 SC, but i haven't wired up the fan yet. Even without the fan running, my car runs fairly cool, though admittedly it hasn't been too warm here.

My question is thus... do I *need* to wire up a switch for the fan? Why not just wire it via the thermostat, or better yet always on?

Besides the "added switch" coolness factor, whats the utility of the switch, esp vs. wireing it always on?

Input/ opinions appreciated!

Thanks!

Chuck

Actually the thermostat setup would be better.
You don't want to run it when the temps are too low, you'll just be cooling cold oil, which can be bad.
Just make sure that you have a correct size fuse in the circut-

I have a manual switch and the only time I power on the fan is sitting in line at an Auto-X.

I have a manual switch on my Mocal setup and I probably would opt for an adjustable thermostat next time. I have been guilty of not paying attention to oil temps (my temps will rise to about 200F and level off without the fan on) and forgetting to turn the fan on. The factory's thermostat setting was something like 245F? That's way too high. I'd set it much lower.

Mike

I can't imagine having a problem of "cooling cold oil".

The oil won't flow to the front of the car until the thermostat in the right-rear fender opens up at something like 182-190 degF. Once it does...you can prevent further upward temperature creep by manually starting the fan.

The stock front fan thermostat opens at 244 degF..too warm, although you can opt for a BMW or C2 piece that opens at lower temps. Having some judgmental control of sub-systems is not necessarily a bad thing.

---Wil

I have rigged up a manual switch for my 88 but have a question about the BMW/C2 thermostat. What, exactly, is replaced in the front oil cooler. Is this just a drop in replacement that causes the fan to come on at a lower temp?
TIA

Buck:
Ahh...yep..the thermostat itself is changed out....both have the same 14mm connections...this is for the later oil coolers that have a threaded bung for this...my 85 oil cooler ( same radiator style)...doesn't have a bung.
--Wil

i have the switch. i put it in, thinking i would need it. i dont think my car has even gotten hot enough to turn the fan on automatically. but i have it just in case.

I wired mine directly to the fuse panel, it turns on with the ignition. I didn't feel like fighting with a relay and a thermostat, seems to work ok. I also made a nice fan shroud from raw fiberglass for it, its pretty much badass.