Brake Pedal Wobble & Diagram

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Buster1
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Brake Pedal Wobble & Diagram

Post by Buster1 » Fri Jan 07, 2022 4:41 pm

Hi guys. Can anyone help me with a parts diagram of the M38 brake pedal ‘hub’ and cross shaft? I can’t locate one. I think there should be a bushing inside and spacer washers on each side.

I pulled my wobbly pedal shaft today, and there was no bushing.

Thanks for any advice!
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Re: Brake Pedal Wobble & Diagram

Post by Buster1 » Sat Jan 08, 2022 12:39 pm

I’ve been reading this discussion too. Some good options here.

viewtopic.php?t=66685

Seems the M38 shaft is 1”, as is the opening at the bottom of the pedal arm (that likes to oval out). So some serious reaming of the pedal opening would be required before a bushing could be pressed in.
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Re: Brake Pedal Wobble & Diagram

Post by Ron D » Sat Jan 08, 2022 2:21 pm

Hi Buster,
That's a discussion of MB/GPW parts. Pretty sure they're similar, but not the same as M38.

This thread (with photos) might be more useful to you. http://willysmjeeps.com/v2/modules.php? ... al+bushing

The M38 manuals have several illustrations, and the parts are listed in the ORD9.

Good luck!
Ron D
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Re: Brake Pedal Wobble & Diagram

Post by Buster1 » Sat Jan 08, 2022 2:59 pm

Thanks Ron! That’s a thread I haven’t seen, and I’ve read quite a few today researching this!

I found a local machine shop and left a message. I hope they can assist me. I think the ream & bushing option might be the best way to go.

I’ve also NOT been able to source the Pedal Slack Kit (through-bolt thing). But may also look to make something similar in addition to the Bushing option.

I’ll keep everyone posted here.
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Re: Brake Pedal Wobble & Diagram

Post by Ron D » Sat Jan 08, 2022 3:21 pm

I recall seeing a NOS Pedal Slack Kit for sale several years ago. I think they're very rare and hard to find. I recall a couple of threads where ingenious folks made one of their own that seemed to do the job. Even though it seems to be a Willys part (or at least endorsed by them), I'm not convinced it's just a band-aid or Willys would've started putting it on them all? In other words, if all the parts that are supposed to be there are in good shape and greased regular, then there should be no need for a pedal slack kit?

Here's some detail about the Willys Pedal Slack Kit: https://cj3a.info/tech/pedalslack.html

I've also seen NOS pedal arms for sale, not too expensive.

On a related note, because the clutch pedal shaft has no grease fittings for the ball studs on each end and has to be disassembled to grease them, I modified mine for grease fittings. Shown in these photos:
http://willysmjeeps.com/v2/modules/gall ... .sized.jpg
http://willysmjeeps.com/v2/modules/gall ... .sized.jpg
http://willysmjeeps.com/v2/modules/gall ... .sized.jpg
Gotta wonder why Willys didn't do something simple like this. What's 2 more grease fittings?
Can’t take credit for the idea, saw it in a post somewhere.
Good luck!
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Re: Brake Pedal Wobble & Diagram

Post by DieFledermaus » Wed Jan 12, 2022 3:54 pm

The M38 has a bolted-on (versus CJ, which is riveted/welded) pedal tube bracket that is bushed and has a zerk fitting. If you are going to get in there, might as well replace it. I have several NOS. Not expensive. It will help take the wobble out of the pedals.
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Re: Brake Pedal Wobble & Diagram

Post by Scrumps » Fri Jan 14, 2022 6:40 am

Duplicate post.
Last edited by Scrumps on Fri Jan 14, 2022 6:44 am, edited 1 time in total.
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Re: Brake Pedal Wobble & Diagram

Post by Scrumps » Fri Jan 14, 2022 6:41 am

Hi,

I bore out the end to 1 1/8” and press fit a phosphor bronze bush (1 1/8” OD x 1” ID x 1 3/8” long) and then drill through for the grease way.

Bushes cost me about £4.50 from Fleabay.

https://www.ebay.co.uk/itm/AI161824-Oil ... 635-2958-0

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Re: Brake Pedal Wobble & Diagram

Post by Buster1 » Tue Jan 25, 2022 6:12 am

Hey guys, thanks again for the help and info. I Wanted to update everyone on my latest.

After calling 3-4 machine shops (all but one said they wouldn’t touch auto parts) I had the brake arm reamed and a bushing installed. I also too Mike’s advice and ordered a new US made clutch tube. My tube bracket looks great BTW. I took the clutch tube with me to the machine shop so they could ensure a perfect fit bushing. I’m really happy how it turned out!

Additionally, I found that my original installation was missing one of the large tube washers. I have all new washers ready and they seem to be a shave ‘thicker’ or wider than the originals on the Jeep. I think that might also be a good thing to help shore up any slop.

I do have some ideas on a homemade pedal slack bolt, but will hold off on doing that for now. I think this will be a solid fit for years to come, but can always add the pedal slack bolt later pretty easily if desired.

What is odd to me in the engineering, is really the only thing preventing a developing ‘arm wobble’ over time is the large washers held in with cotter pins. Seems a loose design.

Anyway, thanks again!
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