Farmall A Crank pulley won,t come off

On a 1946 Farmall A, having trouble getting crank pulley off to replace front oil seal. There was no bolt holding pulley on and the center is threaded, threaded abolt onto it but won"t budge.

It is a very tight press fit. A bearing splitter is needed behind the pulley or it will break. The puller must have serious capacity (3/4" threads on the push bar.)
Several have been made and can be found in the archives.
Heating the pulley with propane is OK, with Oxy torch risky. Heat will toast the seal, so cleaning up the shaft and hole before putting it together is a good idea. It needs to be a press fit, but not excessive. Be sure it goes in all the way to its limit. Jim

Thank you I will give it a try

You need a $100+ puller with 2 prongs, the bearing separator will not handle a 3 prong puller. When it lets loose you will hear a loud bang and think you broke something -- the rest is easy. If you have an O'Reilly's Auto Parts nearby you can rent a good puller for well under $100. If you don't return it within a specific time, you have bought it, for less than you could otherwise. I have done that on two tools I needed.

Joe, here's a picture of what I used, as Mr. Nicholson and CNKS described. The threads you are describing are internal, in the crankshaft, but have nothing to do with the pulley, except that you can use those threads to pull the pulley back on.
As CNKS describes, I had a big-*ss bearing separator, and tightened it good behind the pulley. You want it to press against the thickened
'shoulder' on the back of the pulley that is only maybe 3/4 of the width of the pulley itself. [u:59de37552e]Don't[/u:59de37552e] pull on the perimeter of the pulley, or it will break.
In my picture, the upper and lower arrows point to the jaws of the puller overhanging the bearing separator. The question is then where to put the 'point' of the puller, since you don't want to bung up the internal threads. I screwed a bolt into those threads (I think they're 7/16's), and then drilled a 'divot' onto the center of the head of the bolt, as a 'seat' for the point of the puller, because otherwise it wanted to 'walk' around the head of the bolt.



I heated it with a propane torch for maybe 15 minutes (or it seemed like that long) until it was too hot to touch, and then cranked on the puller, even WAY harder than I thought was prudent, and as CNKS said, I heard a LOUD *bang* and thought I broke something, but it was just the pulley starting to slip. It had to *bang* one more time before it started to come off easier.
Don't forget to inspect the part where the middle arrow points, where the seal rubbed. I put on a speedi-sleeve. Don't want this worn area to muck up your new seal.

Thank You all for the help especially the picture its worth a thousand words. Thanks again.

Here's what Bigdog made for his Cub. You could make one to fit your A or have a local metal shop make one and use 3/4 allthread with a hydraulic jack or ram. Hal