1922 Studebaker EK negative caster issue

[1922bigsix]

My 1922 EK has some tendency to wander when driving straight ahead. Its not too bad but I know it is not correct as my 1921 EG tracks straight and does not wander. I've checked the toe-in and it is OK and camber looks fine. In contrast the car has a negative caster (top of the steering knuckle is further toward the front of the car than the bottom). I believe it should have a positive caster (top rearward of the bottom).

The caster is determined by the attachment of the springs to the axle. Each spring is sandwiched between a front spring plate on top and a front spring seat on the bottom between the spring and the axle. These are shown in the attached image in which the front of the car is to the right. On my car the front spring seat (on bottom of the spring) is thicker in the front than in the back and the front spring plate (on tope of spring) is thicker in the back than in the front. This causes the front of the axle to tilt forward and produces a negative caster. I think that if I reversed the direction of the plate and seats the axle would tilt back and create a positive caster. I assume that at some time in the past the front axle was removed and when replaced these items were reversed in orientation causing the negative caster.

This reversal may also explain the unusual orientation of the throttle / timing quadrant on the steering wheel. The quadrant is at the bottom of the steering wheel on my car instead of on the right as shown in the owners manual.

Will reversing the front spring plates and seats solve the caster issue or am I missing something? I have looked at the mounting on by 1921 EG but the seats are plates are not the same and have less front/back asymmetry. If you have a 1922-24 EK, I would like to know how the front spring plate and seat are oriented in your car. Any help would be appreciated. Thanks.



Tom

[stude8]

Your problem is related to the "Caster" angle of the king pin and someone has already added a caster "Angle Shim" but it could be the wrong angle or like you suggest installed reverse of the position it should be.

I will attach some scan copies of the adjustment proceedure from early Bendix Feragen service manual the explian the correction process and a photo of a bronze adjustment shim. This has fixed at least 3 cars I know of on this forum in the past [see aaca forum post# 260637] also #676414 *this answer has been altered from what I submitted??.

Stude8

[stude8]

Well I see this forum has had some changes in the search methods since I last used it a year or so ago.

To find the past forum entries related to the "Caster" adjustment procedure, do the following steps.

1 in the black color tool bar at top of screen above click on the word "Search"

2 When the search page opens, click on "Advanced Search"

3 When advanced search page opens, in the "Keyword search box" type in the word "caster".

in the "user name box" type in the word "Stude8"

in the "Search in forum box" scroll down and click on the title "AACA general discussion"

the system will then post all the related past discussions in blue lettering that will open to the subject when clicked on.

[stude8]

To save the search hassle, here is the text from a 2004 previous response:

For what its worth, 30 years ago when I bought my 1930 Studebaker President (20" wire wheels) the front end had a bad tendency to "Shimmy" usually right about 35MPH which was provoked when you hit a mild bump in the road. After several wrong tries to fix it, I by chance met an older gentleman with years of shop experience and he told me about "Angle shims".

They are available? (Were available) in 1/2 degrees increments up to about 4 degrees and came in various widths for what ever size your front springs are. They loosened the front spring ubolts and insert the shim so as the increase or decrease the caster angle of the fixed front axle. With age the front springs lose their arch so this is a slowly progressive malady, the caster angle slowly moves until the front end becomes prone to oscillation when driving over less than perfect pavement.
There are instruments that used to attach to front wheel spindles to measure the caster, (you had to support entire vehicle on stands and use a water hose as a sort of U-tube manometer to equally locate each wheel hub center to the same elevation) I even have a few that I collected over the years, only had to use them once. The car was fixed permanently the first time. Stude8

[farmerfrank]

Tom,
I have a 1923 EK and had a few minutes last night, so I checked my spring plates for you. They are oriented exactly like yours.

Gary

[1922bigsix]

Tom,
I have a 1923 EK and had a few minutes last night, so I checked my spring plates for you. They are oriented exactly like yours.

Gary

I reversed the spring pads and the car had a positive caster of about 5 degrees. This corrected the tendency to wander but steering was too hard. I got some 1-1/2 degree shims from a local alignment shop and added two to each side and the caster is now reduced to about 2 degrees positive, the car does not wander and the steering is light. Changing caster had no effect on the position of the steering wheel quadrant as I wrongly had suspected it might.
Tom