danhar1960 Posted May 22, 2011 Share Posted May 22, 2011 I can only reiterate my previous comments on the drum diameters, anchor pins and adjustments. If the drums have been machined oversize and you have std linings, you'll have an imperfect system to start with.It's all about getting the brakes shoes on centre. In a perfect world, the radius on the shoes are the same as the radius of the drum (or extremely close to it). The shoe lining needs to be as close as possible to the drum with the shoes still resting on the anchor pin. That tire movement you refer to is the shoes moving to meet the anchor pin. The less travel away from that pin, the less the movement will be.The shoes need to be centred. If that anchor pin is low, the bottom of the shoes will drag (giving the impression that they are adjusted as you say "can hear the brakes lightly rubbing drums) but still allow a lot of travel piston travel at the the top. Can I suggest trying loosening the anchor pin first making sure it can move up and down freely. Then adjust the shoes to totally lock up the wheels pumping the brake pedal a few times each few adjustment clicks. This will allow the shoes to centre themselves and the anchor pin to find its "happy spot". (If you did this on all 4 wheels, you should have a close to perfect pedal at this point. It might be worth doing it just as a test) Then back off the adjustment a few clicks and then tap down the anchor pin a touch. My '39 has a little slot in the drum for checking that that the shoes are centred by using feeler gauges, not sure if yours does. It's all a bit of a fiddle around session but you will eventually get them there. I know it's going over old stuff but......Danny Link to comment Share on other sites More sharing options...
old-tank Posted May 22, 2011 Share Posted May 22, 2011 Ok, it looks like you have the hydraulic issues sorted out, now you need to adjust it. As Ben stated adjust the push rod for the master cylinder so that there is about an inch of travel before the internals of the master cylinder are moved.Next jack up all 4 wheels and adjust the shoes to the point that the wheels cannot be turned. Adjust the parking brake cables so that all slack is removed but no more. Check the brake pedal travel now---it should little or no travel. Next back off the adjusting star at each wheel 15 clicks...the pedal should go 1/4 to 1/3 of the way to the floor. If still no joy, drive the car safely with lots of stops to seat the shoes and maybe grind off some burrs that are interfering with the adjustment. Repeat this procedure for all future adjustments.Willie Link to comment Share on other sites More sharing options...
Guest Mike Hanning Posted May 22, 2011 Share Posted May 22, 2011 I have found the m/cyl. spring supplied with some rebuild kits is too short, (shorter than the original). Check the residual line pressure valve, (check valve), is seated and functioning properly. Make sure the check valve rubber seat washer is installed at the head nut. Everything looks OK in your photo. But the spring might be wrong!A rule of thumb indication of the correct spring length can be determined during assembly of the master cyl. If the spring is the correct length you will need to apply a small amount of force to push the piston fully into the cyl. bore to enable you to engage the push rod retaining circlip in its locating groove. It is also important to ensure the m/cyl. piston is returning fully, it is necessary to have clearance between the end of the push rod and the piston in the released position. With the m/cyl. installed in the car and full of brake fluid, remove the filler cap and as you depress the brake pedal approx. the first inch of travel you should see an initial spurt of fluid from the compensating port in the reservoir. Given the condition of the linings I would take your drums and shoes to a brake shop and have the shoes relined and the drums machined if necessary to ensure they are all the same diameter per axle set then the shoe linings ground to match the drums. Carry out a major adjustment procedure as part of the re-assembly process and you should have great brakes.This braking system is well engineered and designed and the easiest to bleed on the planet so carefully follow the shop manual and take note of what I have suggested. I have been working on early Buicks for 50 years - I started young though.Hope this is of some help. Best regards from NZ, Mike. Link to comment Share on other sites More sharing options...
60FlatTop Posted May 22, 2011 Share Posted May 22, 2011 Last year I had my '60 Buick rear brake shoes relined. It seemed pretty simple. But my drum would not go back on. After a phone call where the vendor blamed everything from my locating pins, lack of lubricant, and my Grandmother smoking Chesterfields I took the shoes in to their shop.He immediately saw they had installed the wrong thickness lining. It was too thick.I imagine that if too thin a lining was used it would take up the travel of the wheel cylinders and give the problem of poor braking at the wheels. Something to double check. Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted May 22, 2011 Share Posted May 22, 2011 Ok, it looks like you have the hydraulic issues sorted out, now you need to adjust it. As Ben stated adjust the push rod for the master cylinder so that there is about an inch of travel before the internals of the master cylinder are moved.Next jack up all 4 wheels and adjust the shoes to the point that the wheels cannot be turned. Adjust the parking brake cables so that all slack is removed but no more. Check the brake pedal travel now---it should little or no travel. Next back off the adjusting star at each wheel 15 clicks...the pedal should go 1/4 to 1/3 of the way to the floor. If still no joy, drive the car safely with lots of stops to seat the shoes and maybe grind off some burrs that are interfering with the adjustment. Repeat this procedure for all future adjustments.Willie As usual, Willie makes some great points. I would never have thought of adjusting all out tight and checking pedal travel/feel. Ben Link to comment Share on other sites More sharing options...
Guest brh Posted May 23, 2011 Share Posted May 23, 2011 Ok, it looks like you have the hydraulic issues sorted out, now you need to adjust it. As Ben stated adjust the push rod for the master cylinder so that there is about an inch of travel before the internals of the master cylinder are moved.Next jack up all 4 wheels and adjust the shoes to the point that the wheels cannot be turned. Adjust the parking brake cables so that all slack is removed but no more. Check the brake pedal travel now---it should little or no travel. Next back off the adjusting star at each wheel 15 clicks...the pedal should go 1/4 to 1/3 of the way to the floor. If still no joy, drive the car safely with lots of stops to seat the shoes and maybe grind off some burrs that are interfering with the adjustment. Repeat this procedure for all future adjustments.Willie+1 Just keep in mind you bought the car like this, its bad enough making a change and causing another problem or running down a problem that has come up. My point is, cut yourself some slack, you'll get it, I think your getting close. Link to comment Share on other sites More sharing options...
danhar1960 Posted June 3, 2011 Share Posted June 3, 2011 Oi Shadetree,Had any success yet?? Curious to find out what the final solution is/was:confused::confused:.Danny Link to comment Share on other sites More sharing options...
Guest shadetree77 Posted June 10, 2011 Share Posted June 10, 2011 Oi Shadetree,Had any success yet?? Curious to find out what the final solution is/was:confused::confused:.DannyWell....sort of. After I put in the new mc rebuild kit the pedal no longer faded during the mc test and after bleeding some more I had a little more pedal than I started with. I also found a small leak under the car at the junction block where the two back lines split off which I fixed. After this, I adjusted my brakes out a little bit more and adjusted the pedal linkage out some and got it up to about half pedal which is enough to stop the car pretty well. Its far from perfect and I think I need to do some adjusting on my anchor pins in the near future which may just give me a full pedal. I'm currently re-building/replacing the gas tank and fuel system so the brakes are on the back burner for the moment. The guy I bought it from apparently never drained the old gas out before he dumped some new fuel in and started it up after it sat for 30-40 years because the gas I got out of this tank was the color of sorghum molasses!! I can't believe the old girl was actually running on that crap! It finally caught up to her though. My fuel lines are completely clogged. Dropping the gas tank tomorrow to see if it's salvageable. Anyway, I'll check back when I make those anchor pin adjustments to let you know how it went. Link to comment Share on other sites More sharing options...
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