Electric fan electrical hookup ?

[ke6dcj]

What would be the best way to electrically hookup an electric puller radiator fan (replacing the viscous fan) to a M104 engine with HFM?

I'll hookup the power with a 25A fuse to an unused fuse terminal, and a relay, but where should I get the signal from?

I can't "tap" into the "blue" A/C aux. fan temp. sensor because I measured 5V to ground.

Any ideas?

Thanks in advance,
:-) neil

[Benzmac]

I would use the fan off of a new C or E. They seem to be very efficient. Mercedes even did away with the auxillary fans because this ONE is sooooo good.

I would get a variable controller from Pep Boys and wire it in...Put the probe in the radiator fin. I have one on the 16v and it works great.

[ke6dcj]

I too would like to use the current C or E class fan, but the fan motor is too THICK between the pullys and the radiator.

I found a SPAAL (sp?) fan that's 16-inch in diameter that pulls 2500 CFM at 25A 12VDC, but it will have to be off-center. Any problems with off center?

Yes, I've seen the probes that goes into the radiator fins, but IMHO they are hokey.

Any other ideas?

Someone mentioned just running the aux.fans at say 90-C?

:-) neil

[ke6dcj]

I'm replacing the viscous fan for three reasons:
1) more HP while tracking the car;
2) better airflow while idling either in traffic or at the track waiting for my session;
3) better airflow for air conditioning, esp. since I changed from R12 to R134a.

The Spaal (sp?) fan I'm using is rated at a whopping 2500 CFM. However, I do like the Derale temp. sensor module. I hope I can find it fairly local.

Thanks,
:-) neil