Just got my ride, fresh build. Has front straight Ford axle with 60's Econoliner drums up front and drums rear. Pedal has minimal movement, takes tremendous amount if foot/leg pressure to brake at all and braking ability is poor. Any ideas to improve brakes with my set up?
4 Wheel Drums are killin me!
- Thread starter 31ModA
- Start date
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Yankee Transplant
He started out with nothing, he still has most of
Hope you find an answer I have the same problem .. you couldn't slid the tires if you had both feet on the pedal .. correct ?
Yankee Transplant
He started out with nothing, he still has most of
I have a 15/16 wheel cylinders on the rear and 1 inch on the front and a 1 inch master cylinder .. I thought they were kinda matched up but Im not sure if this is the problem A man told me to get a smaller bore master and it should work .. I havnt done it yet been spending money on other priority's so far . I'll try and find my old post and maybe you can get some ideas from it .
Impossible to slide or skid, have to keep distance in mind always to stop...
RPM
The Rat Master!
Can you make the pedal longer? Sometimes just another inch will make a big difference. It will change the ratio and increase the line pressure in the system.
Torchie
Well-known member
There is definately something wrong with your setup. I have driven non- power assisted drum brakes only on BIG cars for years and never had that problem.
As I recall there was quite an extensive thread on that very problem. I believe it was on this site.
Do some searching and maybe some will chime in with a link.
Good luck.
Torchie.
billy
Motor mouth ratchet jaw!
Torchie
Well-known member
Go to the search function at the top of the page and type in "Hard brake pedal"
Many threads. On the 2nd page is one titled M/C bore size. Ielieve that it has some good links.
Most seem to say that the bore on the MC is the culprit.
Hope this helps.
Torchie.
Many threads. On the 2nd page is one titled M/C bore size. Ielieve that it has some good links.
Most seem to say that the bore on the MC is the culprit.
Hope this helps.
Torchie.
Yankee Transplant
He started out with nothing, he still has most of
ModA I commented on my old thread to bring it to the top . Ive got the same problem maybe look threw and get some ideas ..
smallfoot
He's rockin' the "Nuttin Special"!
I would think if you have matched up the master cylinder bore size and number of ports, lined the brakes to the proper ports and still don't have much brakes...you can handle most of that with what has been mentioned already...make your lever work for you. If you scour different repair manuals, they are all over the place with bore sizes and line sizes and different sized wheel cylinders. Tweek the brake lever. The lever, one of man's earliest and most important tools...
junker39
Well-known member
Is it power brakes? If it is, make sure you have a good vacuum source to the booster. I had the same exact problem with mine. Not enough vacuum to help out. I had to rig up an electric vacuum pump. Pushing as hard as possible and it wouldn't even hold the car still idling until I got the pump set up. Good luck.
zzrodder
It ain't grey hair, it's chrome!
Problem is likely one of two things - wrong master cylinder bore size or wrong pedal ratio.
Rule of thumb on the pedal arm is 6:1 - if the big arm is 6" long, the small arm is 1" long & so on.
Smaller bore master will make more pressure with less volume of fluid moved, larger bore master will move more volume of fluid with less pressure.
Drum brakes don't require as much volume of fluid to work as discs as you will notice on the typical disc/drum master cylinder - the reservoir for the discs is much larger.
Rule of thumb on the pedal arm is 6:1 - if the big arm is 6" long, the small arm is 1" long & so on.
Smaller bore master will make more pressure with less volume of fluid moved, larger bore master will move more volume of fluid with less pressure.
Drum brakes don't require as much volume of fluid to work as discs as you will notice on the typical disc/drum master cylinder - the reservoir for the discs is much larger.
Yankee Transplant
He started out with nothing, he still has most of
modA , did you get your problem fix on your brakes ???
smallfoot
He's rockin' the "Nuttin Special"!
This is a cool thread. Lots of same ideas. Is there a hydraulics expert in the house? I'm not having trouble with mine yet, but I'm not far enough along with it to know yet. I've heard the same stuff over and over all my life. Bigger cylinder, more volume....smaller cylinder, more pressure. My question is this. If the wheel cylinders are not in question here on size, what do the different processes mean at the wheel cylinders? If you send more pressure from a smaller cylinder, what would be the result of sending more fluid from the bigger cylinder on the same system when it arrives at the wheel cylinder??? Wouldn't sending more fluid down the same size hole create more pressure at the end of the run??? I'm stumped on that....I don't think I've ever had a master cylinder with less than a 1" bore and several were manual brakes with drums all around. Most of the early vehicles had 1" and more MCs....at least the ones I was into...even the Harleys.
I'm still just thinking that the lever ratio can improve any problems there. Boys, I'm here to tell you..if we all just had one more inch eh?
I'm still just thinking that the lever ratio can improve any problems there. Boys, I'm here to tell you..if we all just had one more inch eh?
Yankee Transplant
He started out with nothing, he still has most of
My pedal is to low to add 1 more inch small foot .. but i am going to try it just to see if thats my problem ... ModA must be hard at work on his problem .. havnt heard much out of him .. maybe he's got his fixed ..
but i am going to try it just to see if thats my problem ... ModA must be hard at work on his problem .. havnt heard much out of him .. maybe he's got his fixed ..
Yankee Transplant
He started out with nothing, he still has most of
I know the feeling if its not one thing its another
smallfoot
He's rockin' the "Nuttin Special"!
My pedal is to low to add 1 more inch small foot ..
Ok, if you can't add an inch to the overall length, you can still increase ratio by going shorter between the axis and the actuator rod. You may have to move some stuff around but that would be a way to gain leverage.
echnidna
Well-known member
At a guesstimate I reckon you need a m'c bore of 5/8"
