Author Topic: Is the AUX fan really needed? (Read 3350 times)

Rosales · « **on:** April 12, 2010, 11:16:27 PM »

I recently installed a volvo electric fan to my car and Ive noticed that it pulls a lot harder than the mech fan. As it sits right now its wired into the AUX fan plug since I had a junk one laying around. So living in AZ, do you think I need the aux fan in addition to the new stronger electric fan?

Romrog318is · « **Reply #1 on:** April 12, 2010, 11:36:17 PM »

do u still have the condensor in the car?

Rosales · « **Reply #2 on:** April 13, 2010, 09:16:23 AM »

Yes I do.
The original AUX fan that was on the vehicle was inop but the AC still worked well.

Romrog318is · « **Reply #3 on:** April 13, 2010, 01:19:14 PM »

if its on high then it will cool plenty i have it on my M52

monty23psk · « **Reply #4 on:** April 13, 2010, 07:19:13 PM »

If you car is standing still for longer periods of time and its hot, the AC can run warm with out the AUX fan. That is the only reason you would need the AUX fan as the engine temp will be fine with the Volvo fan. I replaced my aux fan with a SPAL and it removed the fan clutch. This way with AC on, it cools the condensor and the engine. And if using the car with no AC, and engine temps rises, then new aux fan kicks in to cool engine.

wannam42 · « **Reply #5 on:** April 14, 2010, 11:22:42 AM »

The aux fan is critical and it's name is ironic. Once it comes on, it cools down your engine rapidly especially if you're idling in traffic. When the engine temp has come down to the normal level, it switches off.

Why did you wire the Volvo fan into the aux fan plug? That would mean intermittent operation - unless your engine is running hot all the time due to having no full-time fan (mechanical or electrical) or some other problem.

I submit that main electric fans (not aux fans) aren't as good as the visco ones: http://www.aaroncake.net/rx-7/efanmyth.htm

Rosales · « **Reply #6 on:** April 14, 2010, 12:25:06 PM »

I actually just wired it to the aux plug to see if the fan worked and to check if the wires were in order since the original aux fan was inop anyways. Since I removed the mech fan i thought id have a cleaner set up through the unused plug.

doitover · « **Reply #7 on:** April 14, 2010, 09:10:00 PM »

I'd hate to cause anyone harm by giving bad advice but I have been running with no fan since last July or so with no problems. I believe there are many others doing the same. On one 100ish day I saw the gauge creeping up while sitting at a light.

Shortly I'll finish installing an inexpensive electric fan to handle that. I haven't been running the AC due to a bad clutch on the compressor. Once fixed that load might be enough to cause a problem.

dwtaylorpdx · « **Reply #8 on:** April 14, 2010, 10:20:45 PM »

My 1995 318ti with M42 came only with an electric fan...

Dave