Crying Uncle on '66 wagoneer brake job. What am I missing?

[AZOutdoors]

AHHHH! 1966 Wagoneer. I have completely replaced everything in my brake system except the power booster. New drum pads and springs, wheel cylinders, hard and soft lines, and master cylinder. I bench bled the master cylinder (twice) I did this by filling it and waiting until fluid came out of the ports, and then I plugged the ports and slowly pushed the piston in repeatedly (15 seconds in between strokes) until bubbles stopped. This was per the instruction s that came with the master cylinder. The piston was firm when I finished. I adjusted all four drum brake star wheels so the wheel makes about 1 turn when I stop spinning it. The emergency brake works. I bought a power booster pushrod adjustment tool and adjusted the push rod to .020" shy of touching the master cylinder piston. I bled the brakes manually and then with a vacuum bleeder. The problem is the pedal easily goes to the floor. I jacked up the back wheels and put it in gear and they stop just as the pedal reaches the bottom of the travel. I just did a check on the power booster and if I hold the brake down and shut off the engine, the pedal almost immediately starts going up. I think during that test it should stay put for at least 30 seconds so I am going to order a new booster. Could that be the issue? I assume there is a solid mechanical path through the booster to the master cylinder so a bad booster it seems would be less effective but not allow the pedal to easily go to the floor. Am I missing something? Thanks in advance for suggestions.

[tgreese]

Drum brakes have shoes or linings, not pads.

Did you adjust each wheel with the self-adjuster wheel before assembling? I have this tool https://www.amazon.com/GearWrench-3377- ... B0002SQUJ0 If you adjust by turning the wheel through the hole in the backing plate, you need to tighten the shoes so they are tight against the drums, then back off until the tire/wheel turns. The shoes need to be seated so they are an even distance from the drums. The caliper above is the fast way to adjust them - it's what the pros use.

Or you still have air in the system. The pedal should be hard regardless of the booster condition. If the pedal is not hard before you start the engine, the shoes are too far from the drums, or you have air in the system.

If you get your initial adjustment right, the brakes will work well enough that you can drive the Jeep and do the repeated-backing-up maneuver to finish adjusting the brakes.

When I bench-bleed, I make tubes that curve back to the fluid reservoir.

benchbleed72TSM.png

This is from the '72 TSM. Are you following the TSM? The '74 TSM is free to read and download on the Tom Collins site, and it covers drum brakes.

[AZOutdoors]

Thanks for the suggestion tgreese! Right....new shoes. Sounds like I did not adjust the pads correctly. I only adjusted them through the hole once assembled and I did not get them tight and back them off as you suggested. And.... I just ordered that tool and it will be here tomorrow. I will let you know if that does the trick. Thanks again!

[SJTD]

When you back off the star wheel you need to push the adjuster in so the star wheel can move. Look at a pic of drum brakes on Google or in the manual to see why. It's a ratchet arrangement and you can hear the adjuster clicking when you turn the star wheel.

[AZOutdoors]

Thanks SJTD. I had to push that adjuster stop with a small screw driver from the backing plate adjustment hole to loosen the shoes when I removed the drums. Once I get them snugged up I will have to remember to do that to loosen them.

[tgreese]

You did not mention your drums. What did you do there? The easiest is to replace them all, otherwise you must recondition them. They can be turned to as much as 60 over in diameter (typical value - it's printed in the drum). Common machine shop practice - your local Napa or old-time parts store can likely do it too. They'll have a dial caliper specific to measuring drums, and will guess at whether they can be saved.

The shoes will wear into the drums some, and create a lip at the outer edge of the drum. This both prevents the drums from coming off without backing off the adjuster, and makes installing the drums with the caliper above less accurate. And uneven drums shorten shoe life. Unlike rotors, drums are routinely reconditioned.

[AZOutdoors]

I owe you a drink next time you are in Arizona tgreeese! I bought your suggested brake shoe adjustment tool and that did the trick. I was surprised how much further the shoes needed to move out (vs my adjustment with the drums on until they seemed to drag since I didn't adjust them until they were tight and back them off). I did turn all four drums and the mechanic said he only had to kiss the surface. Bottom line....I took it for its first drive after sitting in the Arizona sun for 28 years!!!

[tgreese]

Woohoo!

[devildog80]

So.....there is hope for mine after all, as it only sat for 18 years

Good job, and look forward to running with you some day, with our Wagoneers!

[Stuka]

Thats awesome! 28 years is a long time!

[lkmarsh]

Congrats for getting the brakes working. And your jeep looks perfect!

[1978J10REDWHITE]

Love the patine, wet sand it and put 10 coats clear on it keep it antique looking..

[AZOutdoors]

Great suggestion. That is the direction I am leaning..... Trying to decide what color to paint the rims. The passenger sides are grey and the driver's sides are white for some reason. I am also thinking of putting on a more original looking tire with a little more aggressive tread.