Has anyone successfully replaced the viscous fan with an electric one?
If so, any caveats, and what size, brand, and from what other vehicles
would work in a W124?

During track use at Willow Springs, the viscous fan at lock-up seems to
be drawing 10-15HP.

TIA,
:-) neil
1988 360TE AMG

I have seen some kits that you can purchase to controll an electric fan. It slides into the fins of the radiator and turns on and off the fan at the temperature you set.

I would find a fan that would mount inside of the factory shroud.

Neil,
Flex-A-Lite makes a fan that should fit the bill. It is the Electra-Fan II , #30 that comes with an adjustable thermostat.

I shopped a couple parts houses in San Antonio and came up with a price near $200. Let me know if you find a better deal. --tom

I converted mine with good results. The electric fan was the same diameter as the old viscous fan. The problems I encountered were finding a low profile model; most don'e give you enough room to clear the engine block. I ended up with about 2 cm clearance; it was no problem. I got mine through Jeg's aftermarket parts; order their catalog. I THINK the web site is JEGS.com. Also, prefit the fan guard in place BEFORE you zip tie the fan to the radiator. I had to drill a small whole to route the wires which you may not be able to do if you cut the wires too early. I wired mine directly to the battery so the fan would run after the motor was turned off. (I got tired of parking the car for 5 minutes in the summer to start up the car and find the temp redlined. I NEVER had a problem with the battery running down.)

In hind sight, I would rather gone with a two-fan set up, each with their own temp guage. One to come on at 90 degrees C and the other at 100 degrees to "stage" the cooling. But, this would require you to fabricate a thin shield to route the air flow since you probably wouldn't be able to use the old fan shroud.

Good luck,

Intruder

My wife's Peugeot 604 Turbodiesel had a 12 blade fan that worked off a magnetic clutch. This was the primary fan. The secondary fan is a 25 amp electic (13 blades). The primary fan and clutch self destructed and I removed all signs of its existance. I wired the the secondary electric fan into the primary thermostat and I've never had a cooling problem using the secondary fan as the primary.

Robby