7060 Jack Bolts

Well here I am again folks. To remove the castings from the rear axles on my 7060, I need to make the jack bolts that loosen the wedges which clamp the castings to the axle. I tried a 7/8" fine thread cap screw but the threads per inch are not the same as in the wedge. A 7/8 fine thread is 14 TPI and a thread gauge indicates the interior thread in the wedges is 13 TPI. As such it looks like those jack bolts are a special thread.

A tractor salvage yard might have some.

Four bolts, absolutely for the double bushings style.

Been there and dun that too many times. Two bolts does work some of the time BUT, there are times that FOUR pusher bolts are needed !! After you break off an ear on the one bushings you are jacking on, you will soon discover FOUR pushers are the solution to not breaking an ear off.

Well, Allis-Chalmers sure could have saved a lot of $$$$ by NOT providing four pusher bolts then. You do it whatever way you want. And I'll do it the way I want.  I've apparently had some wheel axle bushings much tighter than anything you've ever experienced.  By telling others they will never ever need to use four pusher bolts is just foolish. Have a great day!!      And by the way, I have seen a broken bushing. I was the one who did it by trying to use only two pusher bolts.

Edited by DrAllis - 11 Nov 2018 at 3:44pm

I think I know what your talking about but in case not could you explain what your talking about, have any pictures. If allis. Supplied them is there part numbers. Thanks

Edited by Mikez - 11 Nov 2018 at 8:24pm

as a side note,didn't someone say they C/IH used a jack bolt with same demensions? 7120 maybe

Dave,

You can borrow those bolts from Pentagon.   You don't have to make them.

Don't know if they are the same,but I looked up bolts for the XT;part #70235674- takes 3 bolts in this application. I googled that # and found an outlet for them for $83 ,I would hope that is for all 3?? I suppose that might be less expensive in the end vrs. labor setting up and machining from scratch ?

Just to add a little clarity, the D19/190/200/D21/7000 use the smaller trianglular hub, which only uses 3 bolts to hold it tight, but they also use all 3 holes tapped 3/4" Coarse to use the smaller jack bolts. The 210/220 use the bigger 2 piece wedges, (and jack bolts 7/8" -12)which have 3 bolts on each half. The thought of 3 jack bolts used on these is because the one half has tapped holes, the other half does not. It seems to me the need for 4 jack bolts came later in the 7000 series run, the 7010/7020/8010 only use 4 bolts to tighten the 2 wedges(a way to cheapen the cast hubs) and I think all 4 bolt holes are tapped for jack bolts. If the hubs are tapped for 4 by all means use them if you have them. But if only 3 are tapped, well, that answers that lol! Now, lets all have a beer and shoot the $h!t! lol!

Edited by injpumpEd - 12 Nov 2018 at 12:38pm

If you need a 7/8-12 tap, looks like they aren't too expensive.  I just ran across this on google.  I think it might be cheaper than the usual price for a standard bolt tap of the same dimensions!  

Ed:   You are absolutely correct.  Lots of the two piece bushing sets do not have tapped 7/8 -12 holes to accept the jack bolts in  the dowel half. I just checked  approx. 30 sets of 3.625   3.750  4.000and found that about half of them did not have tapped holes for jack bolts.  Maybe that is why the service publication does not mention using four jack bolts.  

 Can you see the triangle wedge on the axle? The pusher bolts go in the holes that currently have the 3 regular bolts in them to tighten the wedge on the axle. The pusher bolts are tapered to loosen the wedges.

This is for Marv, but others please comment if I got it right.

Open up the Agco parts book online for 7060, go to page 302.
Study that. The bushings have bore inside to the axle diameter, tapered on the outside to fit the tapered hole in the wheel disk. The bushing #7, with the 2 pins also has a machined in key to fit the key way slot on the axle. I presume the lip of that bushing contacts the wheel face. This bushing therefore locates on a face, a tapered bore and two pins, and locates the axle concentric with the wheel. It is highly constrained dimensionally, so must be machined right.  Three 3/4-10 bolts secure it to the wheel.

The other bushing, #8, the simple one, is placed in there and then it's (3) 3/4-10 bolts are tightened. Because of the taper in the wheel disc and matching taper on the bushing, as the 3/4-10 bolts are tightened it is wedge locked tight. The lip on this bushing doesn't contact the wheel.

How to take it apart to remove wheel or adjust thread width.
You have to pop out loose the #8 bushing some how. Remove the (3) 3/4-10 bolts securing bushing #8. Now come the use of the jack bolts. Little design details. In the wheel disk are the 3/4-10 threaded holes. They are not drilled through, but rather are blind holes. The (2) end holes in the head lip of #8 bushing are threaded 7/8-12. The holes function is as clearance holes for the 3/4-10 bolts. Other function is they provide threads for the jack bolts to do its job. The jack bolt- imagine a 7/8-12 full threaded bolt, 6" long. Now turn down the end to maybe 5/8" (to clear the 3/4-10 threads), 3" long.
Insert the jack bolts into #8 holes, engage the threads. The point of the bolt will clear the 3/4" threads in the wheels holes. Eventually the tip of the jack bolt will bottom out in the blind hole of the wheel. Now turn hard with a wrench and you have a pushing out action to force that tapered bushing out loose.
At some point the bushing #7 also got threaded 7/8-12 on its holes. This is the two or four jack-bolt debate.

Obviously the three pusher bolts on the non-keyed bushing design wasn't good enough. That's why they "re-designed" it to four pusher bolts in BOTH bushings.  For those of us that have had to use all four pusher bolts (because two wouldn't get it done) we noticed that the whole wheel center gets pushed off of BOTH bushings. They are stuck to the axle, which is why sometimes two pusher bolts is inadequate. Any other questions ??