brake pedal too high

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Ok, so you just replaced the master cylinder and that is the result? Id say you may have found the problem being only the MC and not the length of the pushrod. I converted two power brake cars (one drum and one disc) over to manual and just used the same MC bolted directly to the firewall. They are both the same as in your posted pic. Maybe that MC is for a power application and the snap ring style is for manual????
 
Back in the day my friend had a '72 duster factory 318 & 3spd trans. Everything was original & his brake pedal was about an inch higher than the clutch pedal. Same thing in my other buddy's '71 duster w/ slant 6 3spd. I always assumed it was designed that way so the clutch pedal wouldn't interfere with hitting the brake pedal in a panic stop situation. Both were manual brakes if I recall.
 
OK I finally had a chance to go out into the garage and work on my brake pedal being too high. I thought I had the wrong master cylinder but the trouble turned out to be I didn't have the push rod and that little rubber keeper all the way seated in the end of the piston. See what I found when I pulled it out in pic #1.

My push rod is original to the car (1867 Barracuda) and it came with the four piston fixed caliper disks. When I went to the larger ball joint and more modern sliding calipers I used this push rod with a manual disk/drum master cylinder for a 1974 Duster. The push rod for my car is right at 6 inches long from the piston end to the center of the pivot bolt. See pic #2.

When the push rod is fully inserted into the piston, it goes in right at one inch. You can see from the mounting face of the master cylinder to the center of the pivot bolt it shows 5 and 1/8 inches. If you add the space between the mounting face of the master cylinder and the end of the piston (where the snap ring retainer is) you can see it easily subtracts an 8th of an inch from my 5 and 1/8 measurement therefore giving me a full inch of depth to the piston recess. See pic #3.

The blue tape marks the depth of the insertion from the mounting face of the master cylinder. See pic #4.

With the push rod fully inserted into the master cylinder my brake pedal is where it is supposed to be in the resting position, even with clutch pedal. I thought this was going to be a exercise in "musical master cylinders" but when I realized I had never fully seated the push rod into the MC piston I was relieved it was a simple fix.
 

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bombers gotta be right,i got a pushrod from a scamp.my pedal sits a little high.i used a napa master cyl for man brakes. it stops the car just fine.
 
I don't see the problem, a lot of you see, with a welded pushrod. Mind you I ain't real thrilled with using a mig welder, for this job, but properly tig welded, i was regularly going 126 MPH with mine. Column strength of the base material is what does the work, not the weld.
I'm a maintenance tech at a worldwide tool and die company, believe me I hear about safety daily and don't wanna injure MYSELF or My WIFE, either. I felt it nessacary, when shortening my own, to run a tap inside of it and thread the thing to allow fine adjustment and straightness, before welding.
 
I felt it nessacary said:
This sounds like a great idea if you want the pedals to be even on a stick car. Also tig welds do not break easy compared to mig. Sheet metal can be butt welded with tig leaving no seam. I tried a sample . You can take a mig butt weld and break it with one bend. a tig you can bend all day like its part of the two pieces you welded. It just keeps bending with no fracture. Steve
Click to expand...
 
mopardude62 said:
OK I finally had a chance to go out into the garage and work on my brake pedal being too high. I thought I had the wrong master cylinder but the trouble turned out to be I didn't have the push rod and that little rubber keeper all the way seated in the end of the piston. See what I found when I pulled it out in pic #1.

My push rod is original to the car (1867 Barracuda) and it came with the four piston fixed caliper disks. When I went to the larger ball joint and more modern sliding calipers I used this push rod with a manual disk/drum master cylinder for a 1974 Duster. The push rod for my car is right at 6 inches long from the piston end to the center of the pivot bolt. See pic #2.

When the push rod is fully inserted into the piston, it goes in right at one inch. You can see from the mounting face of the master cylinder to the center of the pivot bolt it shows 5 and 1/8 inches. If you add the space between the mounting face of the master cylinder and the end of the piston (where the snap ring retainer is) you can see it easily subtracts an 8th of an inch from my 5 and 1/8 measurement therefore giving me a full inch of depth to the piston recess. See pic #3.

The blue tape marks the depth of the insertion from the mounting face of the master cylinder. See pic #4.

With the push rod fully inserted into the master cylinder my brake pedal is where it is supposed to be in the resting position, even with clutch pedal. I thought this was going to be a exercise in "musical master cylinders" but when I realized I had never fully seated the push rod into the MC piston I was relieved it was a simple fix.
Click to expand...
Good thing you found that problem! That could have spoiled your day!!!
 
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