Fan pulley replacement

Tue Mar 26, 2013 6:11 pm

My handcrank won't work, and I'm pretty sure it is because the fan pulley is stripped. I can get a replacement pulley. How do I remove and replace the pulley? The manual refers to tools (FES 33-1), which I don't have, nor do I know where to get them.

Re: Fan pulley replacement

Tue Mar 26, 2013 6:36 pm

Unless you have a front seal leaking and needing replaced at the same time I'd forget it and leave it alone.
The front boltster will need removed and a puller applied to the pulley to remove it.
I'm sure someone will post a link showing the process.

Re: Fan pulley replacement

Tue Mar 26, 2013 6:57 pm

Suspect the problem is with the hand crank rather than the pulley. The crankshaft pulley is cast iron. The ramped lugs inside the pulley that match the hand crank are rather substantial - to the point of being massive. The lugs seldom break without damaging the entire pulley.

Re: Fan pulley replacement

Tue Mar 26, 2013 7:29 pm

I am with what Eugene said, what does the pin end of your hand crank look like? Are you sure it is completely engaging into the pulley?

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Re: Fan pulley replacement

Tue Mar 26, 2013 8:10 pm

I suspected the crank, since it was worn and have replace it with a new one. I have the front end off and the pulley is obviously damaged.

Re: Fan pulley replacement

Tue Mar 26, 2013 8:19 pm


Re: Fan pulley replacement

Wed Mar 27, 2013 6:37 am

Follow the threads that Bob attached to his post, if you want to build a puller set-up. You might also check to see if someone nearby has one you can use. If you purchase an aftermarket pulley, be aware that some of them do not have a timing notch on them. You would do well to determine the proper location for the notch and cut it with a file, before installing the pulley.

Re: Fan pulley replacement

Wed Apr 17, 2013 6:10 pm

Well, I got it off, thanks for the assistance. Now the task is getting the replacement on. I started to draw it on using a half inch bolt, but the key is getting pushed out the back. Any advice?
Also, I wanted to chase the threads with a tap, but all I could find was a 14 TPI tap. I believe the correct thread for the crankshaft is 1/2 - 13 TPI. Is that correct?

Re: Fan pulley replacement

Wed Apr 17, 2013 6:58 pm

1/2" - 13 is the correct thread. If you are pushing the woodruff key out the back, are you sure you have the right size key? Sometimes they become a little deformed when removing from the shaft and they don't fit properly in the keyway anymore. You may need to replace it with a new one. Also, you could try putting the key in the freezer and then driving it into the keyway with a rubber mallet or dead blow hammer. I also put the pulley in an oven and let it get hot enough to make the installation go a little easier.

Re: Fan pulley replacement

Wed Apr 17, 2013 9:26 pm

Thanks, What is the correct way to install the key? I just left on the shaft after I removed the old pulley.

Re: Fan pulley replacement

Thu Apr 18, 2013 6:32 am

You might try lightly tapping the front end of the key to seat it a little lower. It should level out as the pulley is pressed on the shaft.

Re: Fan pulley replacement

Thu Apr 18, 2013 7:35 am

The pulley needs to be heated and it needs to be installed quickly. 250 degrees is fine- too hot and you will cook the front seal. I use a length of HARDENED threaded rod and an impact wrench to drive the pulley on. You need to be very careful at the end as once the pulley bottoms out you can snap the rod. No matter how you do it you should measure and mark the pulley so you know how far you have to go as there is no other way of telling.

Gary Dotson wrote:On installing the front pulley: First, take a depth measurement inside the seal and transfer the measurement to the pulley snout and make a mark (sharpie works good). That will give you a visual reference for when the pulley is fully seated. Then, warm the pulley (a yard sale toaster oven works great) to about 250deg. Have your installer tools are laid out & ready, so you can install the pulley as quickly as possible. It won't stay hot as long as you'd like and will start to warm & expand the crankshaft, so work quickly.