[Farmall] Gear puller

[Karl Olmstead]

Thanks to all of you who had suggestions on how to pull that stubborn 
steering gear on my F-12, I got it done.  Actually, I pulled two of them, 
just for practice.

John Wilkens told me about an American-made gear puller called "Posi Lock". 
I looked them up online and on ebay, where there are normally a few of them 
being offered.  Since I believe that "bigger's better", I bought the 30-ton 
unit, which appears to be one step down from their biggest puller.  Weighs 
44 pounds, and will grab a 17" diameter gear.  I used a 3/4" drive ratchet 
to crank on the drive screw, with a handle about 30" long.  After applying 
most of my weight to the ratchet handle, I warmed the gear up using a MAPP 
torch, since my O-A system is loaned out right now.  Then I whacked the 
puller drive screw with a 4-pound sledge, and the steering gear popped right 
off.  I pulled a second gear a few minutes later just using the ratchet, no 
heat or hammering.  The first gear had been exposed to the elements for 
several years, which might explain why it was harder to pull.

The gear fits onto a tapered shaft, just as you fellows told me it should. 
Two keys cut in the gear, only one in the shaft, for a big woodruff key.  I 
guess the second key slot is so that you can turn the gear around when it 
gets worn.  To my surprise, the bottom bearing on the front bolster on the 
F-12 is simply a bevelled surface on the steel shaft riding on a mating 
surface in the front bolster casting.  No anti-friction bearings whatsoever. 
The top bearing, just below that gear I pulled, is a bronze bushing.

I was so impressed with the Posi Lock puller that I ordered a couple of 
smaller pullers to round out my collection.  Definitely a step or two above 
the old Harbor Fright unit that I broke.

I'm having a tough time with foreign-made tools.  I've been using a (Grizzly 
Industrial) Taiwanese copy of a Bridgeport vertical mill for boring out old 
axle pin holes and for making new bushings.  The power quill feed refused to 
work a couple of weeks ago.. the device that feeds the boring bar (or drill 
bit) into the work.  I tore down the mill this past weekend and found that 
the brass power takeoff gear had gotten munched.  Looks like it got hot, 
siezed up in its bearings, and was destroyed by the steel worm gear driving 
it.  According to Grizzly, new parts are available, which is a major relief. 
Think I'll order a few spares.  Other than this problem, I do like the mill. 
I probably only have about twenty hours of use on it.  It's tight, quiet and 
accurate.

Thanks for helping me through the gear pulling project!  If anyone wants 
pictures of the steering knuckle or front axle re-bushing projects, let me 
know.  I took plenty of pictures.  I'm stopped on the front axle bracket for 
now; I need the mill to finish boring out the new bushings.

Eventually I want to develop a procedure for inserting a bronze bushing in 
F-12 front bolsters to make the hand start crank easier to turn.  That cast 
iron hole in which the crank turns gets really worn and sloppy after 70 
years of use.  That's another tricky project, because it is difficult to 
figure out where the original hole used to be now that it is not round or 
straight.  And the hole is at an angle on a piece that isn't straight or 
square.  Setup is always tough on things like that.  If I set it up 
incorrectly, the new bushing winds up pointed the wrong way.  Hopefully the 
U-joint in the crank start mechanism will forgive small errors on my part.

-Karl