Drum Brake Springs

I always knew them as primary and secondary, but WTH, I grew up in Utah...

 

Donny, I hate to say I told you so, but Google primary and secondary brake shoes. They are listed that way all over the place.

 

I buy from all over, including Ebay, trying to avoid Omix-ada when possible. Get NOS when I can.

My very rudimentary parts book shows different wheel cylinder numbers for "early" and "late" F-head models. Not sure what that means.

 

That's interesting... What does your parts book list as "late" F-heads? Mine is a '62, built in November of that year... If you have the part numbers, maybe you can send those along. Maybe they no longer mean the same thing, but maybe it is worth a try...


Thanks...

 

As I say, the book I have is not very detailed, or necessarily accurate. No date on the change.
Others here will know more than I do.

Front left and right, "early" = 807356
Front left "late" = 803639
Front right "late" = 803640

(I think the front change may relate to if the input port is straight or angled. Left and right thus differ.)

Rear "early" = 807357
Rear "late" = 938117


If I was in your situation I would consider a close comparison and measurement of old and new parts, especially the cylinder pistons. Just my shot in the dark.

 

Did a F134 CJ ever come with 10" brakes? Seems reasonable that the F134s contemporary with the 225 got 10" brakes. That would be an obvious early-late difference.

 

You can't mix up those numbers for the fronts. The 807356 brake line comes out straight from the cylinder and the 80639/40 angle out, toward the rear (?) That will be obviously different from what you replaced.

 

OK, that explains it. On my CJ, the front wheel cylinders are different than the rear ones because of what Tim said above. Mike from Willys asked me to take a pix of the front cylinders so he could send me the correct ones. There is a difference in the bleeders, too. The front cylinders take a 1/4" wrench to open/close them and the rear ones take a 5/16" wrench. The piston diameters are all the same, however.

I got the shoes on today and also took care of the emergency brake. I has not been working. I put new shoes on it when I rebuilt the D-18 and just hadn't had a chance to get the mechanism working properly. There was a piece that had come loose in the backing plate. It was a press fit and had worn. I modified it and it is solid now. The brake will now stop the jeep, but I need to adjust it, now that I have operated it a bit.

I ended up getting new springs and they make everything work as it should. This, plus the fact that the new shoes are two different sizes like they should be for each wheel. The jeep stops fine, and there is no rubbing like there was before on the original shoes. Between the new shoes and springs, the wheels will spin freely. The other brakes must have been rubbing from the start. The jeep appears to have more pep than it had before. because there is no interference from the brakes. It is quite a change. I have also finished the windshield so I can fold it down. I took a ride tonight with it down, and I enjoyed the hell out of it. I installed the seatbelts that the PO had in it when he had it, and they work fine, too. Now I have to figure out the top that the PO had. All I have is several pieces of the top, some with windows a couple of doors and a bunch of metal pieces which I assume is the frame. Looks like a giant jigsaw puzzle to me. I will look to see if there are any tags anywhere and see if I can go on-line to find some instructions.

Thanks for all your input. It was a team effort!!! You all have a great 4th and don't mess with illegal fireworks. I am here to tell you, you can get hurt by them. Personal experience.

Later...

 

Thanks, Pete. Mine are the 807356's and the 807357's Now that I have the right shoes and new springs, everything works...

 

I have no problem being corrected, but I will defer to my British car background for my leading/trailing terminology. You're going to make me look up what the Jeep service manual calls them.
-Donny

 

The answer is "yes" to 10" brakes on a F134 CJ5; as in the CJ5a Tuxedo Park model, at least those with the column shift starting in '64. I assume the later V6 Tux kept them too. The Tux shared brakes with the Commando that came a few years later.
-Donny

 

"Mine are the 807356's and the 807357's Now that I have the right shoes and new springs, everything works…"

Glad you are seeing the reward for all your effort.

To clarify - was the solution the new springs, or changing the cylinders?

 

Pete,
The solution was the springs. The cylinders were fine. As you know, I converted the brakes to power by installing vacuum booster and dual reservoir master cylinder (see pix above)and hanging pedals for both the clutch and the brakes. I was concerned that since the master cylinder was about two feet higher than the old one, that maybe the springs were not strong enough to push the cylinders back to their rest stops. I discussed this with Timgr and he seemed to think that would not be an issue. I think it was a combination of the wrong shoes on the first go-around, weak springs, and not knowing how a "foreign" master cylinder setup was all going to work together. Things seem to be working fine now. The power brakes give me the power to stop the the 31" tires with no problems, even with 9" drums. I am going to drive it for a while and if the rest of the jeep seems to be worth it, I will most likely go to discs, at least up front.

Thanks for your help. I appreciate it. Have a great 4th!!!

 

Donny, I was just messing with you. I don't care if they are called yellow and purple. Just to show you how the Brits and the Americans use the language differently, I have to tell you a story.

I used to work for a branch of the NSA when I was in the military. The place I worked was a joint US/UK venture overseas. I was working with a Brit and he asked me if he could come to my place and catch a ride to work after he dropped off his car at the auto shop close to where I lived. I said sure. The day before, he came over to my cubicle and said, "OK, I will knock you up at 0800 in the morning". I politely told him he would not. Then I explained to him that "knocking someone up" had a totally different connotation in UK than it did in the US.

So call them whatever you want, and I will too. Have a good 4th, or can I say that to a Brit? Are you British or just work on Brit cars? Either way, have a good evening...