1967 CJ5 v6 Pitman Arm Install Mystery

[JohnnyCO]

I am rebuilding my Ross T12 on my 67 CJ5 v6.  I confirmed that the steering box is the larger used on this model (TL122987).  The Sector shaft is also the original (TL124989) and in good condition.  I am replacing the pitman arm because there is pitting on the ball.  He is the mystery I am trying to solve. Here is a pic of pitman arm as I was disassembling the box.  Please notice that there is no space between the box and the pitman arm and the nut is pretty much flush with the end of the sector shaft.

I took it apart, cleaned it up, put the worm gear back in with original bearings (good condition), shimmed to remove all backlash (spins freely), put the sector shaft back in.

When I put my pitman arm back on (original or new), there is a gap between the arm and the box.  I believe that I have confirmed that the arm is as far on the shaft as the splines will allow.  What am I missing here.  It's driving me nuts.

I understand that the CJ5 v6 used a shorter sector shaft.  This is the same sector shaft in all pics.  Any help or suggestions would be appreciated.

Thanks

John

[JohnnyCO]

Here is a pic of the sector shaft by itself.

[JohnnyCO]

And here is a view of the sector shaft during disassembly.  I found a rubber tube inside.  I am guessing the original owner put it to limit travel in that direction instead of adjusting the pitman arm orientation.  

[Moses Ludel]

JohnnyCO...As you note, the pitman arm will only fit so far onto the sector.  That's a fixed distance.  You also note that the previous owner had the cam and lever riding way off center...Was the mesh adjuster screw far out in the side cover?  That would allow the sector to move inward with the pitman arm, closing the gap between the pitman arm and housing.  If you loosened the adjuster and applied pressure to the unopened gear, the sector and pitman would move inward toward the housing.

You now have the gear on center when you adjust the lever pin engagement with the worm.  The only thing that would take the lever shaft too far outward would be worn lever pins.  Inspect the lever pins—a very common wear point on the TL gear.  If they do not show significant wear, you should be okay.  There should be no lever backlash over-center and distinct backlash when the worm-and-lever turn left or right away from the center.

Since you tried both pitman arms and experience the same space between the pitman and housing with each, there is not a spline cut issue.  If only the new pitman spaced outward, that could be a sign of shallow cut splines on the pitman.

Does the lever shaft seal ride in the same position as it did originally?  You should be able to see a faint trace of the seal rubbing point on the sector/lever shaft.

Here's an in-depth guest lecture I did at the Midwest Willys Reunion a decade ago.  This covers questions that arise during a Ross TL rebuild:

https://www.4wdmechanix.com/Rebuilding-the-Ross-TL-Steering-Gear?r=1

Here is more Ross TL coverage at these forums, including rebuilding:

https://forums.4wdmechanix.com/search/?q=ross tl&quick=1

Moses

[JohnnyCO]

Hi Moses and thank you for the quick response.  I don't recall the adjuster screw being far out on the side cover during disassembly and the pins do not seem to have any significant wear.  The shaft seal does seem to ride in the original position.  I am hoping to ask a couple of question which I did not hear answered in the video or elsewhere on the forum.  

1) What is the length of the sector shaft used on the v6 engines?  I know its is 15/16 in diameter but I have not been able to find a simple length measurement to compare against.

2) Is there suppose to be (or can there be) gap between the pitman arm and box body?  Here is the box as originally installed just pivoted down to rest on the frame.  It does not appear to have a gap.

Thanks again for your help.

[JohnnyCO]

Hi Moses.  One more thought.  When I put the pitman on as far as it will go with torquing and push the shaft into the box to eliminate the gap, the pins barely rub on the outside of the worm gear.  This is so strange. Thanks again. 

[Moses Ludel]

JohnnyCO...The V6 designated gear is the same sector/lever shaft as the military M38A1 unit.  Each needed to be narrow to fit within the chassis.  The M38A1 was an F-head four with military equipment under the hood.  The CJ V6 needed clearance from the V-engine.  There is a distinct housing width difference between F-head 134 gear cases and the V6 gear. 

Also, the lever shaft bushings on the military/V6 gear are spaced close together unlike the standard TL gear (four-cylinder type).  One sector bushing on the V6 gear is longer than the other to better support the sector with the short shaft.  Note in the photo below that the two bushings are the same width.  That's an F-134 gear.

If you want to scare the crap out of yourself, note the pin engagement with the worm as you show in your photo above:  The lever is off-center position, and this where you experience backlash.  Backlash is essentially from the pins not being fully enmeshed with the worm cam, which is normal.  The only place to check the pin fit on the worm is in the straight ahead position or "over-center" middle of the steering lock-to-lock turns.  There, you will not have backlash, and the pins will fit into the worm cam.

When driving, the force or road resistance keeps the lever shaft against the adjuster screw.  The worm and pins are tapered and will push the lever toward the adjuster screw when wheel force is applied.  In the off-center position, if you manually pull the pitman arm toward the engine, you can expect to increase the gap between the pitman arm and gear housing.  This does not happen in normal driving.

Note:  When you get your gear all set up, make certain the front wheels/tires point straight ahead when the lever pins are at the over-center position.  Always align the steering wheel to the over-center position.  If you need to center the steering wheel during a wheel alignment, do so at the tie rods and drag link adjustment.  This will assure that the steering gear is on center with the front wheels pointed straight ahead.

You cannot fit a short/V6 sector into a standard TL gear case.  Here is a photo of the F-134 or longer steering sector.  You can get a "proportional" sense for its length.  The V6/M38A1 sector is distinctly shorter:

It looks like you have the short sector.  An F-134 steering gear would be the long sector for a wider steering gear case, which would interfere with your engine.  I'd like to see an interior photo of your gear case with the bushings.  The bushing spacing is the key.  Note that snoopy2x rebuilds his CJ V6 gear in this topic at the forums...Compare your parts to his, scroll down through the photos:

There are some excellent photos, one of the bare housing (blasted) that shows the spacing between the bushings.  Another photo shows the longer sector bushing with a notch on the end for the oil feed hole.  Use the snoopy2x photos as a guide to an original, genuine V6 Ross gear.  The gear housing at the pitman end of the sector has a distinctly shorter casting than a four-cylinder TL gear...Snoopy2x compares the lengths of the sectors, V6 versus four-cylinder types.  I believe you will find answers at that set of photos.

Moses