Clutch adjust problem

[HDowse]

I had the car up on a friend's lift this morning to get an idea of what repairs need to be made to make the car roadworthy. Brake hoses, wheel cylinders, master cylinder, wiring and so on seems normal for an original car. We replaced the Swiss cheese tailpipe, checked and changed fluids and I tried to adjust the clutch.
The free play is about 4" so I figured to lengthen the rod underneath to lessen the free play. I removed the clevis pin but could not turn the clevis because it either hits the frame or the arm connected to the clutch shaft. It also looked as if the adjusting rod was close to the end of its travel. Does that mean the clutch is about gone?

[Admiral]

Four inches of free-travel is WAAAAAAY too much. As I understand it, you only want around 1 or 1.5 inches. To prevent the clutch lever from interfering with the clevis, try pulling it back or pushing it forward ... I forget, just move it the opposite way it's supposed to move when you push the pedal. There should be plenty of movement.

[35fordtn]

Be sure you have the correct 01A clutch shaft. The part # is cast into it. If you have a 51A, or 09A it will give you issues like you have stated.

[40cpe]

Free travel will typically get LESS as the clutch plate wears.

[HDowse]

35Fordtn, thanks, it makes sense that it's the wrong part, too short for the O1A because the adjusting shaft is at the long end of its travel and I have 4" free play. Now to find the correct shaft...

[35fordtn]

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[V8COOPMAN]

Originally Posted by HDowse

35Fordtn, thanks, it makes sense that it's the wrong part, too short for the O1A because the adjusting shaft is at the long end of its travel and I have 4" free play. Now to find the correct shaft...

I THINK 35Fordtn is talking about the 7503 shaft in the drawing below. I could be wrong, though. DD

[35fordtn]

Exactly.. The 01A shaft has a shorter "throw" If a 51A shaft was used you would have to push the pedal farther to have the same result. Not saying that is the problem but a good thing to check. Also if the bushings (01A-7517) are worn out it can cause too much freeplay

[HDowse]

OK, I thought you were referring to pn 7521 but I think I see what you are saying: the throw on the shaft, as determined by the vertical part of pn 3503, could be off if it isn't the correct length. What is the correct length for the correct O1A shaft vertical piece? Either the overall, outside to outside, measurement or the distance from center hole to center hole.
Is there a different #7521 for different applications? The vendors state it is 4.5" long, good for 32-48 years.
Getting at the connecting pin on the inner part of 3503 looks almost impossible. Maybe the floorboards have to come out or at least the metal cover?
All these early V8 details are new to me as I've had Model A's for years. To say they are a little less complicated is true but the changes from my 1928 Fordor to this '40 are really amazing. With my 4:11 gears, I easily ran up a long hill this morning that would have been in second in the A and low in the '23 T.
Thanks for all the help on the Barn!

[35fordtn]

The 7521 part has three different lengths B-7521 being the longest for 1932's, then 40-7521 For 33-34's and last;y the shortest is 48-7521 for 35-48's. The reproduction is long enough to cover all three variations. The reproductions are rather cheesy in my opinion. I would only run a original.

The pin at the pedal assembly is a bear to get to, I recently replaced all these parts on my 40 without having to remove the floorboard.

I'll attach a picture later of all three variations of the 7503 shafts.

On a 1941 I worked on last year I had to use a 40-7521 linkage for the extra length. You may have to do the same.

[HDowse]

I just compared the shaft lengths on Van Pelts and I'm pretty sure I have the correct 7503 but I do need a longer 7521 so maybe the 40-7521 is what I need. If you have such a linkage, send me a PM with details. I appreciate your help.

[35fordtn]

Here are 3 photos comparing a 51A shaft to a 01A shaft. The overall length is the same. As you can see from the side shot the 01A has a shorter throw, and the arm has a bend to it. It would be easy to see which you have as the part#'s are clear to read on them.

Going to a longer adjuster linkage would be a easy solution but it's sort of a Band Aid fix unless yours has been shortened. Yours should be 3-7/8" end to end. And I would still be certain the bushings and clevis, and pins are not worn.

421 130.jpg

421 131.JPG

421 129.jpg

[Bob C]

Also make sure pin 352581-S isn't broken.

Bob

[George/Maine]

You maybe better to make the link longer.
Not knowing about the car it may have a new pressure plate.
The new ones out have no adjusting screws, the original had them to true the clutch and set the contact to throw-out bearing .This amounts to 3/8+/- and changes the play In pedal.

[Kube]

Once you have determined you have the proper pieces installed it is time to check for wear.
It may be as simple as too much wear on the clevis pin(s), the hole in the clutch arm, the hole in the adjusting rod, the bushings in the transmission case, the shaft that rides in the bushings, the "half moon" bushings in the clutch arm pivot, etc.
You would be amazed how all those worn areas add up to what may very well be causing the issue you describe.
There should never be a reason to make the adjusting rod longer. that is simply a "band-aid" approach vs. actually repairing the problem properly.
I would strongly suggest you remove the pieces that rotate in this assembly and check for wear. And, repair any and all wear you find.

[trainguy]

I have found the Clevis pins worn more than halfway thru and the holes worn egg shaped. They are heavily loaded and poorly lubricated. I have had to replace much of the assembly to get the proper motion.Phil

[Charlie ny]

Hunt,
All great ideas but since your '40 is a super nice survivor I think Mike
nailed it...especially the 1/2 moon bushings 7517. The grease fitting on 7503 may
have been overlooked in the last 76 years. 7517 kind of looks like a full bushing but it is actually 2 half bushings with a radius on the inside dia to capture the ball on
7507.
Charlie ny

[HDowse]

The tips have all been very helpful, especially regarding wear on so many moving parts. It confounds me how I am going to get it all apart, everything is so jammed together in that area. On a Model A you just unscrew the floorboards and everything is right there. Anyway, nothing like a good challenge.
I did some looking last night at the linkages and couldn't see any significant wear. However, until it's all apart I won't have a good sense of the problem.
Many thanks to everyone who has chimed in, Hunt

[V8COOPMAN]

What you may be astounded to realize is that when you take into account the length of the pedal arm, 1/8" of wear in ONE clevis pin's hole can easily amount to more than 3/4" free play at the pedal pad. An additional 1/8" wear on the pin itself can lead to an ADDITIONAL 3/4" or more free-play distance at the pedal. If BOTH clevises and pins are EACH worn ONLY that 1/8", PLUS the bushings at the ball being worn, YOUR amount of free-play is easily attainable. It's the pedal length that multiplies ALL those little-bity distances to a gi-hugic, un-manageable dimension. DD

[G.M.]

Originally Posted by V8COOPMAN

I THINK 35Fordtn is talking about the 7503 shaft in the drawing below. I could be wrong, though. DD

I have found the top of the arm in the area of the wood floor
where the drawing shows an arrow at 7520 hit the floor. This
restricts the working movement of the clutch. I mark the wood
floor where the arm is hitting it and with a round wood rasp in
the electric drill cut a groove for the arm. I have had 4 or more
1939's that I thought needed a new clutch and this solved the
problem. Also the 7527 rubber bumper should sit in a recess in
the wood. If it don't go in the recess that can be a problem also.
G.M.