MYFord Super 7 quick change gearbox questions – bushings

[Sub WooerParticipant @subwooer63862]

I'm in the process of replacing the bushings for the gear axles in the QC gearbox. Its going pretty well so far, tapped out the tapered pin, removed the two axles with gearing, removed the upper bushing and replaced it, as well as the lower silver colored outer bushing on the bottom axles. BUT, the oilite that rides inside the silver colored out bushing is very tight to go in. When I was taking the gearbox apart, this bushing was very loose and rotated freely out by itself. I am sure it will tap in, but isn't this bushing supposed to rotate on the silver bushing? Its very tight to enter. I am a little worried that it wont want to spin later, or is this just a part that goes in tough and wears TO the outer bushing after the first few hours of run in? I'm 99.9% sure it is the correct part that I am trying to use..

I was getting a lot of oil leaking from this bushing before teardown (when filling the nipples, not the gearbox oil) so I assume that it was well worn (previous owner used grease instead of oil in the nipples so it would make a lot of sense that it ran dry and wore out.

I'm also curious about the reinstallation of the shaft that has the keyway and tapered pin in it. What is the reinstall process? I took it apart in a convoluted way, but once it was apart, and after I felt how tight that bushing is to re-enter, I realized that perhaps the best way is this:

-slide axle into position from the right, threading gears on as I go.

-install tapered pin in gear #1 (check orientation carefully with caliper to find the big taper ends of the gear and axle).

-install the keyway from the right and align gears as it gets inserted. tap it lightly till it bottoms out on the #2 gear.

-tap in oil light inner bushing over the axle and inside the silver bushing

-screw in end cap and washer

Thanks for any advice!

[Sub WooerParticipant @subwooer63862]

[Dave HalfordParticipant @davehalford22513]

Not familiar with this gearbox, but Oilite bushes normally fit firmly on the outside and run smoothly to shaft size on the inside.

[Philip RoweParticipant @philiprowe13116]

One thing that a lot of folks seem to be unaware of is that oilite bearings are deliberately made oversize and the action of pressing them into the housing will reduce the bore down to the correct size. Phil

[Sub WooerParticipant @subwooer63862]

Phil, thats interesting.. so just push away and go for it?

The difference in diameter is about +.15mm

[Dave HalfordParticipant @davehalford22513]

I hope the outer bushing isn't loose.

[Sub WooerParticipant @subwooer63862]

I used a custom press to push it in. I think its tight enough that it wont be the first to spin.. its also a harder material (steel?), so I suppose all things equal, the brass will yield before it would.

I suppose a worst case is that I press the inner one on, it wont let the axle spin, and I press it out and turn it down .1mm.

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