I need to replcae the Fan Clutch Assembly on a 1985 F150 with a 4.9L 300 CID I6 engine. I remember that there is a simple way to do this but I don't remember what it is. The fan bolts to the fan clutch assembly and the assembly has a shaft on it that has a large nut on the end of it that screws onto the water pump.

Can anyone give me a simple procedure for replacing this? Maybe the trick to breaking the nut off the water pump shaft?

Someone told me they think the bolt and shaft may be reverse threaded.

If I am standing at the front of the truck with a wrench on the nut, do I pull to my right or left to loosen?

 

Most parts stores have the correct wrench for Ford fan clutches as loaners or for sale. Yes it is left hand thread. Move wrench to right to loosen.

 

Thanks for the info. Based on reading since my post, This would be a "flexable" wrench that wraps around the water pump pulley and standing at the front of the truck with wrench in place, I would hold the wrench and place another on the nut and turn it to my right or clockwise. If any of this is wrong, please let me know.

Thanks again for the info!

 

I may be wrong but, I've never known one to be left-hand thread. They used a "reverse-rotation" waterpump but, the nut was always a right-hand thread (normal) The "wrench" should be like a big spanner(?) that goes over the bolts (on the waterpump) and you hold with a ratchet or breaker bar, then there should be a long flat wrench to use on the nut.

 

Thanks for the info, I guess I will figure it out when I rent the wrench, I have found that a 1 3/4" wrench works on the nut but if they have one included in what I rent I will use it especially if it has nothing on the other end making it easier to put a breaker bar on.

Thanks again!

 

If the fan clutch is loose the fan will come off when the engine is shut down, therefore any clutch nut should come off in the direction of fan rotation, regardless of right or left threads.

 

If you don't have access to the wrench, you can take a long metal rod and hammer, and give the big nut a whack on the correct side to break it loose, then simply spin it off by hand.

 

I think it's left handed, but I can't remember for sure. I used a pair of water pump pliars to change it.

 

yes it was left hand thread. mine is the same way on my 85.....i wouldn't suggest hitting the water pump or anything connected to it with a hammer, it can easily trash the seal. nOw after saying that i have successfuly removed it with a punch and a hammer on that larger nut driving i the proper way, so far so good, no screwed up water pumps.