Early Brake type - pulling on one side

Hi,

I'm not familiar with the early style 9" brake on my CJ - The brake was more or less pulling straight a while ago but now got progressively worse. So the routine lately has been to start the jeep in the morning, then once you're on the road, hit the brake a few time to "equalize" them. I don't think its normal to do so, so....

this weekend I adjusted the pad the best I can using the eccentric bolts in the middle of the backing plate (2 per corner) and while it is a bit better it still pull. May be I didn't adjust properly? not sure since it was the first time I did that. The procedure I followed was this:

1. loosen the lock nut
2. screw the 1/4 inch eccentric until the pad made contact to the drum
3. then turn back just a hair at a time till the wheel turn free
4. then tighten the locknut

A bit easier said then done since the lock nut tend to screw up the adjustment. They now grab better but they still pull. If you think its probably the cause then I'll redo the adjustment again.

When I bought the jeep the lines/wheel cylinders/pads were all new (about 2000 miles ago) so I doubt if one cylinder is jammed. I check the front pad when I did my bearing adjustment and they were OK but the driver side was a little more worn.

Please let me know what you think

 

"When I bought the jeep the lines/wheel cylinders/pads were all new (about 2000 miles ago) so I doubt if one cylinder is jammed."
Why in the world would you think that??? My new water pump just failed - within 100 miles. Any recent work is the first thing to suspect.


Could be number of things. A stuck (or leaking) wheel cylinder, or a missing/loose return spring, oil, fluid, or grease contaminination, wrong adjustment.

Did you move the adjusters in opposite directions of rotation, as per the FSM? Locking them requires carefully holding the stud in precise position with one wrench, or vise-grips, while tightening the locknut with another.

Some brake shoes have a "leading" shoe, and a "trailing" shoe in each pair. Are they installed the same, and correctly, on both sides of the vehicle?

 

Yeah... thinking back now - my brand new Omix Ada distributor quit on me - so I should not assume anything.


To answer a few questions raised...

They did pull before the wheel bearing adjustment - I clean them out with brake cleaner to get rid of the dust but they were good - i.e. no grease at that time so the front are clean. Dunno about the back
I didn't drive in sand, mud etc...
Not sure on the drum - I'm sure they were not turned when the new brake were installed but since they were better before than now I can only assume that something went wrong in the last 2000 miles that's why I suspected the adjustment
No scraping sound - I backed off until the wheel turn free with no scraping sound - I was afraid to overheat them if they drag (happen once on my Dnepr)

 

the shoe with the shorter friction material goes to the front.

 

That is true on a single anchor system. On a dual anchor system, the shoe with the longer pad surface goes on the front. As they were talking about cam adjusters, it must be a dual anchor set up.

 

Make sure the inner hub seal isnt spitting oil out. I just had that problem with mine

 

Ditto.

Pivoting at the bottom, the rotation and drag tend to make the front shoe more self-activating than the rear shoe.

 

Ok- I'll re-adjust them again - and goes from there. If that doesn't solve the issue then I'll take a look - the way they were put in may be an issue - The garage the seller used for the brake job were not Jeep specialists so unless there was an clear indication on the pad as to which one goes where or I luckily hit an old timer with experience with these brakes then yes it is possible that they were badly installed.

 

Thanks for the advice... IF the re-adjustment doesn't clear this up then yes I will be focus on the front first since 70% of the breaking power is there. I'll do the rear after that since I have to buy the jumbo puller needed + dig my BFH out of the tool box.

 

longer lining goes toward the front and shorter goes toward the rear. says right in my manual for these old 9 inch jeeps brakes

 

I once changed out the rear shoes on an old VW I had and didn't realize there were leading and trailing shoes. I went through hell, trying to figure out what was wrong, so I pulled both wheel and looked at them. Then I noticed that one set of shoes was larger than the other. I had put both larger shoes on one wheel and both smaller shoes on the other. That's when I realized what a dummy I had been. I had gotten so used to disc brakes, that I didn't stop to think about it. Hope you find your problem quickly.

 

Thankfully we have forum like this to help us all!

 

In my FSM it does say "On some vehicles the lining on the forward shoe is longer.."

I had trouble believing this, and it goes against everything I've ever learned. I have to wonder if was a typo.

The usual set-up is shown here. http://www.agcoauto.com/content/images/brakes/drum/brake_leading_trailing.jpg

 

my manual is a fresh reprint of a service manual for the universal jeep and dispatcher third edition from willys motors inc and has a copyright date of 1957. I bought it from Original reproductions llc their website is originalreproductionsllc.com and the front cover says Service manual at the top. has a red and white checkered front with Universal jeep and jeep dispatcher written on the cover lower right https://www.originalreproductionsllc.com/details.html?cat_id=3
looks to be the third one down on the page is what I bought for use on my 1959 cj5

my manual says and I quote "Note that the lining on the forward shoe is longer than that on the reverse shoe. The shoe having the longest lining is placed forward on all four wheels."

 

both my 48 cj2a and my 59 cj5 have the longer brake lining placed forward and I have great brakes on both. I can lock them up if I want to both have new brakes but napa replacements of the original parts with the exception of my 48 that has been converted to a dual wildwood master cylinder for added safety and the 59 will too shortly