Steering Box and Alignment

There's always been some play in the steering wheel since I bought the car.  A long time ago, I researched this and found that the steering box was the culprit.  There's an adjustment that takes out the play.  This works by moving a cone that's on the sector arm up or down in the worm gear.  The worm gear is turned by the steering wheel and the sector arm has the pitman arm attached with the tie rods that moves the wheels.

Back then, I just adjusted the cone until I had removed the free play.  When I test drove the car, there was no play when going straight, but I almost didn't make the first curve as it was too tight when turning.  The worm gear was worn just in the center area.  That makes sense since the steering wheel is centered during most driving and the wear during a turn is spread out over the rest of the worm gear.  I ended up having to back off the adjustment until it was tight during turns but loose when centered.

So I'm kind of used to having the steering somewhat sloppy.  One of the first things I did when I put the car up on my new lift was an hour of close inspection.  I moved, rattled, wiped and checked everything that I could think of.  During this process I found that the left outer tie rod was worn and that allowed the tire to wiggle about ".  So I ordered a new tie rod end.  I wanted to keep the same geometry, so I carefully measured the length of the adjusted tie rod between the centers of the tie rod ends.  Then removed the bad tie rod end and screwed on the new one until the length was identical.

The other thing in the steering that has always bugged me was that the steering wheel wasn't centered when going straight down the road.  I've had it aligned a couple of times and complained that I wanted the steering wheel straightened.  But either it is difficult, time consuming or they just didn't do it.  After thinking about it, the solution is pretty simple.  I drove the car straight onto the lift with the wheels straight (and steering wheel not).  Then I took measurements from the front subframe to a convenient place on the tire tread.

After noting these measurements for each side, I then straightened the steering wheel and took new measurements.

  Left Side Right Side
With wheels straight 9 9/32" 9 13/32"
With steering wheel straight 9" 9 5/8"

You can see that there was about " difference with the steering wheel straightened.  The left side decreased while the right increased as I was measuring to the inside of the tire in both cases.  So I just adjusted the tie rods to move each wheel to the original measurements keeping the steering wheel straight.  It's easy to move the tires and steering wheel when loosening the tie rod lock nuts so I had to keep checking.  This meant climbing up a ladder I had next to the driver's door and reaching through the open window to keep straightening the wheel.  Much faster than running the lift up and down.

Now back to the steering box.  I have two spares and was told by the previous owner that the best of all three had been put together.  However upon inspection of the one in the car, it still has the ZF lead seal attached, so it has never been apart.  They are supposed to be tight in the center and then gradually loosen as one turns the wheel to each side with it being loosest at the lock point.  One of the spares seems be fine when I adjusted it properly.  So I just need to swap that box in and my steering play should disappear.  Then I'll take it to a good alignment shop to have everything put according to specifications.

I dug out the two spare steering boxes a couple of days ago.  One is complete and feels tight.  The other one is missing some parts and evidently was used for spares.  I took the good one and mounted it in a vise in the same position it would be in the car.  Then I filled it with 80w gear oil.  Normally you use 140w gear oil in it, but I wanted to check for leaks.  If it doesn't leak with 80w oil in a couple of days, one feels pretty secure that it won't leak with 140w oil in it over the long haul.  I also rotated the steering column shaft to different positions every few hours.

Everything seems to be well sealed as I couldn't find any leaks.  I removed the pitman arm that was on the spare box as the nickel finish was chipped.  There's a special puller used (pitman arm puller, duh).

Removal of the steering box in the car isn't easy.  There are two tie rods on the end of the pitman arm.  So you either have to remove these or pull the pitman arm before you can remove the steering box.  There isn't enough room for the puller with the box bolted in.  So I unbolted it and drove it off from the steering column fitting.  Of course one of the nuts is obstructed by the box itself and you can only get a open end wrench on it.  Luckily it wasn't on very tight.  Further, that nut can't be removed until the box is loose and pulled back as the nut hits the housing as it is backed off.  Once the box was loose I could get the puller on the arm, but it was really stubborn.  I was just bending the puller arms even though they are held together by a floating assembly with nuts on each end.

I didn't want to remove the tie rod ends from the pitman arm as that usually damages the rubber boots when you drive the tie rod remover (pickle fork) between the arm and tie rod end.  So I elected to disassemble the tie rods from each end.  I carefully marked where the tie rod, locking nut and tie rod end all lined up.  Then I undid each lock nut and backed it off one turn.  A lots of turns later, each tie rod unscrewed from one its two ends.  Now the steering box was free with just the two tie rod ends still attached to the pitman arm.  I put this box in the vise and set up the puller.  Even with tightening the puller arm assembly nuts, the arms still were bending and trying to slip off the pitman arm.  I eventually took a large C clamp and tightened it directly outside of the two hooks to keep them from coming apart.  Then I applied a lot of pressure to the puller and finally with a bang, the arm came free.  I wasn't sure if something broke or it came loose until I saw the arm free.

Now it was just a case of assembly and installation.  I had already drained the 80w oil, so I put in the 140w.  One thing that I had noticed was that there wasn't a copper washer under the filler nut.  There's one shown in the parts book, but I didn't have one the right size.  None of the three boxes had one, so maybe there isn't supposed to be one.  Anyway, I just tightened up the nut and went about my business.  Then I turned the box upside down and oil started running out.  I was surprised at how much as I thought the nut was on tight enough even without a sealing washer.  When I looked carefully, I found a small hole in the filler nut.  I had assumed that this was for a safety wire, but after closer inspection, it's a breather hole.  So I finished everything else with the box right side up.  The old pitman arm with the tie rod ends attached was put on the new box.  There are marks to properly align the pitman arm on the end of the shaft.  I recently got an assortment of metric cotter pins and one fit exactly for the castellated nut that holds the arm on.

Putting the box back in the car was pretty straight forward.

Steering Box Mounting Location Steering Box Mounted

The only real trick is to get the steering column lined up and driven onto the splines on the steering box.  There are alignment marks on the steering box and worm gear shaft that mark straight forward.  You just have to have them aligned and keep the steering wheel centered as you start onto the splines.

The blue arrow points to the alignment marks.  Once the steering shaft is started on the right set of splines, then you just tap it on a little, move the steering box onto its studs a little more and repeat.  You do have to remember to start the one obstructed nut as soon as possible and then keep tightening it so the steering box doesn't touch it as it moves into place.  You'll notice that the steering column collar doesn't have a bolt in it.  It's supposed to be a 10mm bolt with a castellated nut and cotter pin.  The bolt I took off had two thin lock nuts instead.  And I didn't have a 10mm x 1.0mm castellated nut on hand, so that has to wait until I get to the All-Metric nut and bolt store.  I'll also have to drill the bolt for the cotter pin as it isn't original either.

It turns out that fine thread metric castellated nuts are had to find.  The only source I've found is Metric and Multistandard.  The only issue is that the minimum order is 25 units of the smaller sizes and 10 of the larger.  So replacing this nut would have been ~$35.00 and I would have a several life-times supply.  In the process of working on the PF coupe, I needed several sizes of castellated nuts for the rear suspension.  I was going to bite the bullet and get this size too, but as I was researching sources, I realized that the tie rod end nuts are 10x1.0mm too.  So I dug out an old tie rod end and salvaged the nut (and told my wife I just saved $35 because of this box of old parts I keep around as she always wants to help me clean up).  The bolt was never drilled for a cotter pin so I had to do that too.  Here's everything installed.

The last thing was to re-assemble the tie rods.  As I was unscrewing the long middle tie rod, I noticed the one end moving around in a small circle.  The tie rod had a small bend in it about 5" from one end.  So I removed it and carefully used the hydraulic press to straighten the rod.  Then I just screwed each tie rod back onto the ends until they came close to the nuts.  By turning the nuts down to the tie rod and counting the turns, I was able to determine if I had to screw the rod onto one end further at the start so it would be even between the lock nuts and final position.  A couple of adjustments later, all of the marks I made on the tie rod, lock nuts and ends were in the right place.

Now I just have to replace the worn suspension pins and bushings and the front end will be as good as new.

After having done all of this, I drove the car for several hundred miles on a FCA trip to Canada.  After the trip, I found another bad tie-rod end (it didn't have any play until the Canada trip!). So I ordered one , just using the parts book for the number. When I went to put it it, I found that someone had swapped that tie rod end for end so the bad end had RH threads rather than the LH one I ordered. However, I had replace a couple of others a long time ago because of bad seals. I was able to remove this one w/o damaging the seal and then swapped seals. So I guess it pays to hang onto old parts (at least that is the justification to my wife).  When I tried to remove the other tie rod end from the idler arm, I couldn't get it loose.  So I ended up removing the idler arm after disconnecting the tie rod running to the pitman arm.  Once I could put a bearing separator between the tie rod end and the arm, one blow from the hand sledge broke it free.  I had hit it 30 or so times when it was on the car without budging it.  Here you can see the bearing separator under the arm and an old nut on the tie rod end so the threads wouldn't get damaged.

Here's the idler arm mechanism, tie rod ends and the tie rod that goes to the pitman arm.

Once I had the tie rod leading to the wheel loose, I found that one end was rusted on.  So for now it's soaking with penetrating oil on the inside of the tie rod (which is hollow).

Hopefully after soaking a day or so, I'll be able to unscrew the end and free up the threads so the adjustment will work properly.  I also took the opportunity to clean off the black paint that was on most of the steering parts.  They were originally just nickel plated with nothing else on them.  The plating has some chips and bangs after almost 40 years of use, but it'll do for me.

Since everything is apart on the front suspension, I'm also rebuilding the brakes.  For that story, click here.

The tie rod end did come off after the soaking and about 5 minutes of heat from a propane torch.  So one more problem solved.  However, when I was inspecting the idler arm mechanism, the rubber gasket looked chewed up and when I greased it, all of the grease came out by the top bearing and none at the bottom.  So I disassembled it.  The housing and lower bearing are on the left, the pin and upper bearing are in the center and the end of the idler arm is on the right.

The lower bearing was replaced at some point with a sealed bearing which is why there wasn't any grease being pumped through it.  As it seems fine, I decided to not replace it.  I did make a new rubber gasket to replace the old one.  When the mechanism is assembled, it is easy to catch part of the gasket between upper bearing and the housing which will take a chunk out of the outside and jamb the bearing.  That's probably why the old gasket looked like it did.  The old one is on the left and the one I made on the right.

The next issue was the Zerk fitting on the top plate was cocked at an angle.  Evidently someone got it cross threaded in the past.  I just ran a tap through to clean up the cross threading so the fitting would be straight.

Before After

After assembling the idler arm, it felt fine until I tightened the nuts on the top cap.  That took out a few thousandths of an inch of play and caused the arm to bind slightly.  I had noticed that the lower washer didn't look original as the inner hole was oblong as if someone had enlarged it with a round file.  I decided that I needed to thin the lower washer to remove the binding when everything was tightened down.  After trying a couple of things, I ended up using a small but strong magnet to hold the washer and then grinding each face on the disc sander.  Here you can see the magnet holding the washer.

It took about 5 assembly/disassembly/grinding operations until I got the washer just thin enough to relieve the binding.  Then I re-installed the idler arm mechanism.  One of the things I was going to do was to adjust the center rod (between the pitman and idler arms) so that both arms were in sync lock to lock.  When I started looking at this I saw that the air conditioner belt and bracket were a limiting factor, not the idler arm housing.

Mark on A/C bracket where tie rod end hit Tie rod hitting an A/C belt

So I think that I'll end up having the steering box control the lock when turning to the left to prevent the tie rod from hitting the A/C components.  Then the idler arm housing will probably end up stopping the steering when turning to the right.  Another day, another problem, but at least I got something back together and on the car instead of having to take something else apart.

Even though the steering box that I put in the car felt fine when it was bench tested, I found that it had a couple of hard spots as you went from lock to lock.  In addition, it started leaking after a couple of months.  So I decided to put the original steering box back in, hoping that a lot of the play in the steering wheel was being caused by the bad tie rod ends that I've replaced.  But first I stripped the paint and repainted it.

I'll let you know how it drives in a few days after I've had an alignment done.

Copyright 2001-2014, Kerry Chesbro