Left turn much sharper than right turn
 

I am in the process of assembling a Model A pickup truck using old parts that I have accumulated. It has a 1929 cowl and a 7-tooth steering box. I don't know about the frame or other parts.

When the front wheels are turned straight forward, the pitman arm is angled to the rear by about 11 degrees. I am certain that it should be vertical with the ground. I removed the steering arm that the drag link attaches to (Snyder part A-3131) thinking that it might be bent, but it matches other old pieces that I have.

I have measured the distance between cowl and steering box, and it is the same as on my '28 and '29 cars. I am at a loss. Any ideas that I can try? Thanks in advance, Richard Lorenz

Re: Left turn much sharper than right turn
 

With the front axle on jack stands turn the steering wheel all the way left and see if it hits the stop pins. Do the same for the right turn. Then turn the steering wheel all the way left and right and count the turns. Come back to exactly half the turns and see where the tires point. They should be straight ahead.

Re: Left turn much sharper than right turn
 

You have verified that the steering arm is correct so to me that leaves the length of the drag link as suspect. With the d/l disconnected at the Pitman arm center the steering by turning lock to lock and splitting the difference. Now hold the d/l up to the Pitman, that will show the excess length; is it possible you have used an incorrect drag link?

Re: Left turn much sharper than right turn
 

Are there different length drag links? The vendors only show one.

Re: Left turn much sharper than right turn
 

it is also possible that the arm on the left spindle is bent. with the wheels straight ahead the arm should be directly over the axle.

Re: Left turn much sharper than right turn
 

I wasn't thinking about differences in Model A d/l's. Isn't a '33-'34 d/l about 1 1/2" longer? Richard mentioned "....assembling from accumulated parts...", did someone sell him a Model 40 d/l thinking it was from a Model A?
Regardless, if the steering box is centered and the wheels pointed straight ahead the length of the d/l will show whether or not it is the problem.

Re: Left turn much sharper than right turn
 

Fordors, I was asking for my own information, not to argue your point...

Re: Left turn much sharper than right turn
 

This true but the defect is likely not in the arm.

Probably the front axle is "curled" back around the radius rod, spring perch.

Caused by hitting a large something with one wheel in forward motion, it's a common fault of Model A axles (its actually quite hard to find an axle that is "straight." Most have this fault to some degree.)

With an adjustable drag link, the defect can be "adjusted out." Well, at least the wheels will have "nearly" equal turn left or right.

Joe K

Re: Left turn much sharper than right turn
 

you could also have a twisted sector shaft

Re: Left turn much sharper than right turn
 

Adjustable drag links are available to get the steering wheel centred and in my case, with a shortened pitman arm, like you, I had more lock on one side than the other.
The adjustable drag link enables you to both centre the steering wheel and get full lock both sides.
Keith

Re: Left turn much sharper than right turn
 

Thanks to all who have spent time helping me to figure our what is wrong. I will try to reply to each suggestion.

First, when turning left, the wheel housing hits the stop. When turning right, the right wheel housing does not come near the stop. The drag link I am using is the same length as my other Model a links. The difference in the right / left turning is such that it would not be safe to drive on the road.

The Pitman arm points back about 11 degrees when the wheels are pointed forward. This is really strange. The 2-balled arm that the drag link attaches to is not bent. It is the same shape as 2 spares that I have.

The axle is directly below the spring, and looks to be straight and not twisted in any way.

I checked the location of the rear motor mounts in relation to the cowl and they are the same as on my other cars.

One new thing is that I now remember that the frame came with a drive-able chassis (no body) that was sold to me as a 1930, and I believe that to be correct. Would that make any difference????

An adjustable drag link would correct the problem, but I believe that I can make a similar accommodation by changing the engagement between the worm and sector 1 tooth in the proper direction. The steering box is the 7-tooth type.

Re: Left turn much sharper than right turn
 

To answer Y blockheads question there was a change in D/L length, the change came when the steering coulomb was lowered, --- not sure when, the length only changed 1/4 inch, (I don't believe this is the OP problem ?) I have one of these I am changing to an adjustable to correct the lock to lock after installing a shortened pitman arm .

Re: Left turn much sharper than right turn
 

This because the pivot point (left kingpin) is BACK by the same horizontal distance. (from the axle being bent.)

(assuming of course that your wishbone ball is engaged in the bellhousing, the frame is not bent, or the engine mounts bent.)

Joe K

Re: Left turn much sharper than right turn
 

"but I believe that I can make a similar accommodation by changing the engagement between the worm and sector 1 tooth in the proper direction. The steering box is the 7-tooth type."

Yep! I agree.

Re: Left turn much sharper than right turn
 

Thanks Brian for the answer to my question. Always looking to learn something.

Where do you get the adjustable D/L? I have the shortened pitman arm also.

Re: Left turn much sharper than right turn
 

I also agree. I don't know much about this situation but I have rebuilt my 7 tooth box and thinking about how I rebuilt it, this comment seems like it could work for you.

Re: Left turn much sharper than right turn
 

So lets say he moves it over one tooth in the worm. And (for sake of the question) this places the pitman arm directly vertical where it should be at mid-sector (i.e. steering wheel placed mid-way between the end of steering box travel full right/full left.)

HOw is he going to make up the connection between pitman arm and drag link? The drag link connection is STILL 11 degrees behind vertical behind the centered arm when the front wheels are straight ahead.

Joe K

Re: Left turn much sharper than right turn
 

Yep, as Joe just said, it can't work. If it could work, all you would have to do is turn the steering wheel one turn. The drag link or some bend needs to be changed.

Re: Left turn much sharper than right turn
 

i still say the sector could be tweaked... i've seen it many times on modern sectors so why not on an A..

Re: Left turn much sharper than right turn
 

Richard,
You should have almost ( not quite) 2 full turns lock to lock on a 7 tooth, with center steer position almost ( not quite ) a little over turn from lock of the wheel. See if you have that... and I think you will. Make sure the lock pins have the lock washer on them ( back side) for '29. Ensure your tie rod isn't bent while you're looking at things.... You can inspect from underneath or an inspection mirror from the front if your hitting the locks.
In center steer your steering arm should have a slight forward cant to it ( ball end slightly forward). I have a '29 coupe with a 7 tooth in the shop now and I just did steer eze on it and fixed some front end issues. I know it's AOK. It does have the early drag link on it.

Check these things... and again, make sure the locks have lock washers on them and they are the tall nuts. You might include some photos if possible for a visual to post to us.

Larry Shepard