Wheel Alignment Issue

Did you check your Toe in/out ? I would check that first and that is easy and can be done with a tape measure. Seems like a LOT of money just for an alignment. Then again... I haven't had one done in YEARS!

Well,

I purchased everything one needs to do a wheel alignment on one of these old cars. Three of us checked the alignment and it is within specifications and still drives like crap.

In the service book, on the imperial site, it specifically describes what I am experiencing. It says that binding in the king pins can cause this.  It may well be that the thrust washers are too thick and once the car load is on the king pins it is binding.

In a couple of weeks, I will check that.

What I wanted to know is does anyone have a S-13 1949 coupe or convertible that is apart? I would like and exact measurement of the length of the drag link. Everything is set great, the tie rod's both exactly 22-31/32 and both turned the same amount to get the 1/16 toe in.  But, the steering wheel is at 10 O'clock and not horizontal. The most likely culprit on that is the drag link. I have found multiple specifications in books at to the length. That is why I want to check someone else's to see what they have.

James.

My convertible is not disassembled exactly, but I might be able to get a measurement for you without a lot of trouble.  Not til next week though, after the insanity of this convention week is over.  And I might need reminded.....

When was your front end last rebuilt ? 

When I rebuilt mine (55 Desoto with king pins), I found that the bearings were frozen up with old grease. Also, upon disassembling the steering linkages, all the 'ball' ends on the center link and tie rods were loose to very loose. So everything was rebuilt or replaced. 

Ron

Hi James,

I had a 1949 sedan for some time, and own a 1952 now.  They are almost identical, except that the 1952 has the Gemmer Hydra guide power steering gear.

Setting up the front suspension in these cars is quite an adventure!  Most alignment shops have never dealt with a "Center Point" linkage, so they probably wouldn't know how to set one up.  One thing I have found is that you can never assume that anything on an old car is correct when you get it.  The first thing I would check is the steering wheel installation on the steering shaft.  Make sure your gear is centered (midpoint of lock-to-lock) and then check the wheel for center with that.  I am amazed at the number of steering wheels that have been removed and then reinstalled off-center.  With the wheel and gear centered, the pitman arm should be roughly vertical. 

You are wise to check the drag link.  There were two parts used on 1949-1954 DeSotos.  The first, used prior to 1952 is P/N 1141074.  A longer one was used in 1952 and later cars when power steering was introduced, and the gear was moved back on the frame to clear the V-8 engine.  If you try to use the later one (P/N/1407983) on an earlier car or vice-versa, you will never get decent alignment. 

Another thing to look at is the intermediate arm itself.  That part is removeable and serviceable.  It has two tapered roller bearings in it that are adjustable for tension via a sleeve and shims (see the manual cut below).  Proper function of that part has a huge impact on steering friction and/or slop.  When you are done; your wheel is centered, and the gear is centered with the right drag link, your center link should also be centered.

Lastly, I would have a look at the upper king pins.  On manual gear cars, those were not a bushing, but were actually needle bearings (see the manual cut below).  Those needles are key to low steering friction and low steering efforts. The needles are not serviceable, they are part of the knuckle assembly- R/H is 1311428, L/H is 1311429.

I hope this helps!

Hi All,

Everything is new. After checking everything the car still is not steering correct. Wander and no caster effect.

I found a 1954 tech note that said the factory installation notes to shim the king pin end play until all play is gone is not correct. That the king pins need 0.008 end play or it will bind and wonder. Mine was .002 to .003. 

I also ran a new reamer and got some material off the new bushings as you could see galling on the new pins. We had honed them on a sunnen honing machine. It was TOO good a job and the grease could not get into the pin to bushing space.

I will be putting it back tomorrow and will see what I get.

*****

Another issue came up when we set the tie rods to exactly the same length before we set the toe.  The steering wheel spokes are at 10 and 4 not 9 and 3.  The drag link measures 26 and 13/16 inch.  The parts book and Rare Parts tell me is should be 26-5/16 and 26-1/4 respectively.

WTF!  Anyone out there with their 1949 in the air or with the steering out? I would love to hear what someone else has for the ball to ball center length of their tie rod.

James.

James,

I don't know if this helps or not- but here is the parts book blow-ups of the 1949-1954 steering linkage as well as the parts list for the drag link part.  This is from the Chrysler dealer "All-Cars" parts book issued in 1949 and updated through 1954.

I'm not sure how you are measuring the ball-to-ball distance, since the studs are in different planes and the rear ball has an angled offset.

I sold my 1949 sedan in 1997. but I know that when I had the steering linkage repaired and alignment set back in the 1970's, I had a hard time getting the front-end shop to put needles in the top of the steering knuckles- they wanted to use bushings. They didn't want to replace the thrust bearings on top of the lower bushing either.  I had a hard time getting them to set the 1 lb preload on the center link bearings too, it was loose, and they didn't  know it could be adjusted.  Like you, the steering wheel was off center with equal length tie rods.  That turned out to be the wheel two splines off center on the steering shaft. 

Great Info in this thread!  Thanks to everyone who posted here.

An update...

I put the thing back together with more clearance in the bushings and the thrust bearing and it helped a little. Very little.

After talking with several suspension engineers...they suggested that I source the upper bearings for the king pins and also ignore the book as to the Castor recommendations.

I am about done with putting the spindles back in with the torrington needle bearings, checking the pre-load on the center bearing and checking the box. All are within spec.

The suggestion is to set the Castor to about plus 4 degrees, as opposed to -1 to -3 degrees and see how it drives. If the steering it too hard then to drop back to +2 degrees.

Basically the idea is to put in as much Castor as I can until the steering is just too hard then back off until the steering is acceptable as fat as turning the wheel is concerned. That will get me as much stability as the the suspension design is capable of according to the "experts".

So, over the next few weeks...I will get up to the house out of town 80 miles away where the lift is...and finish up and then start setting the alignment. I did purchase all the tools needed to do my own.

I will swing back in another month and let people know how things went.

James.

Well...

I got the spindles back in with the needle bearings in the upper. I cranked the Castor adjustment bushing all the way back and could only get negative one (-1) on one side and negative one-half (-0.5) on the other before the support upright hit the rear side of the upper control arm. That is all I could get.

I am staring to wonder if I screwed up when I installed the lower pin in the lower control arm. In theory if it is too far rearward then it would limit how far toward zero or positive I could get as far as Castor is concerned.

The book says -1 to -3 on castor. I was at about -2 and that was not enough. I wanted to go to +2 or so and cannot.

I checked the spindles SAI and the side by side difference is about 1/2 a degree of difference. They should be the same, but my turning plates may not be accurate enough for this particular test.

The SAI (king Pin inclination) is with spec so I don't think the spindles are bent.

Pulling my hair out. I will test drive it next week when I am up and see what 1 degree of castor and torrington needle bears gives me. I am not hopeful.

If anyone with a 1949 or 1950 has had their cars on a alignment rack, tell me what the final Castor settings you used and how it drive with respect to self centering after a turn and wander at highway speed. My '48 drives real nice. The '49 Sucks.

***********

One interesting thing. As I go over with a fine tooth comb the Master Parts Books and the Hollander Interchange something interesting has come up.

The Second Series 1949 spindle is the same as 1946 to 1948. The 1950 uses a different spindle, yet the uprights that the spindle attaches to is the same 1949 to 1954.

Since 1949 was only six months in production, I am wondering if Desoto has a delivery problem with the "new" spindle and so they used the old ones as a stop gap measure.

I picked up an 1949 right last year NOS. I just purchased a 1950 NOS left. I am going to put them on the bench and see if I can figure out what changed.

James.

Well, A few weeks back I was able to get the car out on the road and do a good road test.

By and large the car is now self centering after a turn and is not darting around on the road like it has been.

The problem is I have the castor adjuster all the way back to the rear of the upper support pin and it is likely binding or close to it. That is warned about in the service manual.

I am going to drop the lower inner control arm and screw the pivot bar one or two turns to the rear which will move the lower control arm to the front of the car. Theoretically, that will increase the castor by moving the bottom of the upright forward.  I then hope I can get the adjusting cam more centered as well as pick up about one more degree of castor. Trying to get them both to about -1/2 to zero with the cam centered.

Are we having fun yet !

James