300U Manual Steering Arms

This post pertains to MANUAL STEERING only.
I searched the archives but didn’t find what I wanted.
My 300U has the short arms.

Has anyone had any actual experience driving both a 300U with short steering arms and a 300U/350U with long arms for comparison.

The long arms at the box are 11” and at the front 8-15/16”.

I'm not looking for theory here, I would like to hear from someone who has ACTUALLY DRIVEN both and do the longer arms make a significant difference in the ease of steering.

(I am aware of the many variables like tire pressure, lubrication, etc., but all things being fairly equal, do the long arms make a noticeable difference.)

Thanks,
Dell

Better leverage will always make turning a U easier. The difference is directly proportional to the % difference in length.
However! If the gearbox and other components are unchanged, the travel may not allow full turning of the spindles. If both the spindle arms, and the Steering box arms are longer it will make no difference in turning force or sharpness of turn, but the force on the drag link ends will be reduced, and wear on them will be less. I hope this helps. Jim

Understood. Adding an extension to a wrench reduces wear on my wrist and also reduces force (work) required by arm muscles.
If both the gearbox arms and the spindle arms are increased by 50% then the total turning force /work would be reduced by 25%. If all four arms were increased by 50% then the total force/work would be reduced by 50%. (200% / 4 = 50%).
Meaning if both the box arms and the spindle arms are longer the force/work required by my arms on the steering wheel will be less.
I was just looking to see if anyone has driven both, outside of theory.

Thanks and hoping for a peaceful 2011,
Dell

Unfortunately (and with respect) the reality is not yet under control.
The total leverage ratio is a combination of three factors.

The ramp angle of the pin and follower in the gear box. (Not adjustable)

The length of the Steering arm at the box shafts.
The shorter the easier it is too steer due to the drag link moving less distance per inch of steering wheel circumferential travel. Thus the shorter the less effort. The shorter the fewer degrees of spindle rotation per inch of steering wheel rim travel.

The length of the spindle arms. The longer the less effort. Again the leverage is increased, increasing the distance the rim of the steering wheel must travel for each degree of spindle rotation.

The limit of steering is determined in the spindle stops. They are designed to prevent the spindle from turning beyond a maximum point (either toward the tractor, or away). The stop is provided to mechanically limit the force applied to the drag links and gears in the steering box to prevent most breakage, and to limit turning to about a 3 or 4 foot "U" turn around one skidding rear tire.

The limits to any geometry change (of any arm length) must consider whether the gear, ramp, pin and linkages can travel far enough to reach the mechanical stops in the spindle, allowing full short radius turns.

On my 350U the steering box will turn the steering arms about 1 inch either direction farther than the spindle arms will allow.

If I decreased the length of the steering arms on the box such that they would be just that inch less, it would decrease the effort by about 5% (guess). It would also allow the steering box and gears to be able to jamb (If the axle was deflected high on one side and low on the other, and I was turning tight, there might not be that buffer to keep force from the box.)

If (as you were discussing in your response to my answer above) both the arms were lengthened, the effective ratio would not change. One giveth, one taketh away.

An added element is that the drag links would no longer be parallel with the action of their pivot points (basically the ground). This affects the steering in turns dramatically because they are now pushing and pulling differentially when the axle is deflected. When they are parallel (level) one pushes when the other pulls during a bump of one side. If non level, they would not be equal from side to side.

The only advantage to lengthening them both would be to reduce the force on the drag links, but because they would move farther the steering ratio would not be affected at all.

I hope this makes it clearer. A power steering unit from a 460U can be made to work pretty easily.
A PS unit from a 350U will bolt in, but are rare and not particularly strong. Jackson Power Steering can supply aftermarket solutions. Sorry if my earlier post mislead you. Jim

Sorry Dellbertt,
The shorter the radius of the steering arm on the box, the less it travels per steering wheel inch.
Thus the effort is less with shorter arms on the box.
Think of the drive sprockets on a 21 speed bicycle.
To make easier peddling we use smaller front sprockets (smaller radius), the pedal moves farther per inch of chain travel. Larger sprocket makes more chain travel harder pedal effort. Jim

Scenario:
Someone is sitting on the tractor seat attempting to turn the steering wheel.
I am holding the gearbox arm trying to stop the person from turning the steering wheel.
A longer gear arm would make it easier for me to prevent the person from turning the steering wheel and harder to turn the wheel.
A shorter gear arm would make it harder for me to stop the movement and easier to turn the wheel.
Wait a minute.....whose point am I proving here.....

So why did IH make both gear and spindle arms longer on late 300U and all 350U tractors if not to make steering easier........

Dell

The forces on the shorter arms were such that the ball and socket ends wore out faster. I think they also had issues with bent drag links (compression loading was higher)
The final reason was that the shorter they are, the greater the looseness created by wear in the joints, or spindle bearings.
The total geometry remained the same.

A power steering system from a 1958 ford auto has a ball joint mounted control valve. I can imagine one of these on either side, with a bracket to attach the cylinders to the front bolster. Just dreaming, Jim

Jim,
Thanks for the input. As well thought and convincing as it is I still have a feeling it should steer easier with longer arms.
So the only thing to do is to install a set of the long arms to see for myself if it does indeed make a difference.

Thanks,
Dell

Longer arms on the spindles only, not on the box,(lets say 2 inches) will for sure make it steer easier. It will also not change the angle of the dangle in respect to the ground.

It might not steer all the way to the spindle stops, due to increased travel. Thus there may be reduced turning radius. It also might allow the steering box to continuously run up against its internal limits. (I do not know if this is bad, but those mechanical boxes are fragile.) Jim