The Ford Barn - Radius Arm

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- Model A (1928-31) (https://www.fordbarn.com/forum/forumdisplay.php?f=3)

- - Radius Arm (https://www.fordbarn.com/forum/showthread.php?t=316364)

Hello guys. I was greasing my Tudor the other day and noticed the previous owner had disassembled the radius arm. The spacers and springs are missing that hold the ball in place. It was just put back together with the castle nuts. My question is would it be a wise choice to just put the whole kit in and be done with it rather then just replace the spacers/sleeves and springs? I was wondering if replacing the wick for the oil is a pain in the hump? Any insight would be greatly appreciated.

Any chance you have the rubber ball setup.

I believe that’s the set up I have. I was just hoping their wasnt some hidden tricks on how to replace it

My car is a 30 Tudor. Built in June of 1930 so it has the oval Speedo. Early 30 I suppose. So I’m not sure if all the A’s had the springs?

You can change the Wick and bolts with the motor still in the vehicle, if you have small hands and a magnet and a good light. I've done a few of them, 10min job or 1 hour job,you just never know.

I believe if the radius ball has the rubber ball over it, it wouldn't have the springs. Look at both the kits from the vendors. The original has the springs and the rubber ball kit does not, if I remember right.

The question is, what made the previous owner think he needed the rubber ball set up. Is your radius ball worn?

Nothing seems worn. I just noticed their was no springs just the castle nuts so I wanted to add the springs if necessary

The diameter of the stock radius arm ball is 1.5". When the ball is worn, it affects the tilt of the front axle. If the ball is worn, have a new one electric welded to your radius rod. Then use a stock metal socket assembly to attach the ball to the flywheel housing. Avoid the rubber ball because it wears quickly and degrades when wet with motor oil.

Thanks I appreciate your responses!

I have used both original and the replacement version. There is a small difference in front axle "tilt" between the two - but it doesn't seem to affect driving in any way (i.e. I can't detect a difference.)

As mentioned the replacement seat and cap should be "solid" - as in no springs or other "cushion" introduced between the seat & cap at the bolts. Cushion/free play is made in the rubber ball. Meanwhile the original relies on a sleeve around each bolt AND a spring to make the "cushion" part occur between seat and cap at the bolts. Seat and cap are "solid" around the ball.

I'm not sure one has advantage over the other. Change-over from one to the other with the engine/flywheel housing in place relies on small hands/forceps/magnets - and the bolts MUST change as the replacement cap system the bolts are longer. It's fun when the bolt drops out of the forceps inside the housing.

I had difficulty particularly in putting the bolt "keeper pin" in place. Only by expanding the slot in the top of each bolt was it possible to actually put the pin in and have it pass through entirely, retain the bolts from turning, and be caught by the small cotter pin. Of course expanding the slot requires removal of the bolts, grinding the slot, and then replacing. Time consuming in iteration and much easier done with the flywheel housing removed and on a bench. (retrospection here...)

Good luck in any case!

Joe K

Wow you have inspired me to leave well enough alone LOL!! Everything seems to be operating as it should so I’m going to Cruze on! Thank you for the detailed information I love to learn from all of you friendly A owners!!