W124 fantom cooling problems

[bennkishh]

So here's the deal, I might as well introduce myself in this post too. My name is Ben, I'm 18, and I have a black over grey with grey leather 1991 W124. 3 liter non-overdrive autotragic. I've been enjoying it since I've been driving it but the cooling system is less than stellar.

Brief history of the system during my ownership:

- bought needing a waterpump. Installed and works great, but kept overheating and leaking coolant
-found leak: heated washer fluid elements were cracked, leaking all coolant in to washer reservoir and out through the cracked bottle. Bypassed that and it worked like a charm.
Noticed the radiator was stopping the clutch fan from spinning, addressed that as well.

Now the car runs cool as a cucumber while driving, but slowly overheats in stand still situations, leading me to believe that the electric fan may be in-op. I've been in the fuse box and it makes contact with the fuse and the fan, but the fan doesn't always see to come on when the temp rises, shooting all of my coolant all over the floor during an overheat.

So I guess my real question is simple, could it be realistic that my electric fan is busted, and how difficult is it to replace it?

Thanks a lot guys! I've had wonderful experience on the Porsche side of this site,so I'm hoping for the same experience over here