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Old 11-16-2013, 08:43 PM   #1
88Ironduke
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Help: Power brake conversion pedal really low

The subject is a 72' Long bed, 2wd with non-power brakes....

I've been trolling thru the power brake conversion search tool and haven't been able to nail down my dilemma. I found one thread that gets into booster push rod length and such but abruptly ends when its gets good (where I need info).....

I picked a booster and master cylinder combo package on the forum, then got the power brake linkage/brackets here and mounted everything up. The parts went together nicely, moved the lines, new proportioning valve and I thought I was good to go. I went under the dash and my brake pedal is just a little higher than my gas pedal... Its like the link between the pedal and the brake booster brackets is waayy to short. I'm working solo here so any input is welcome. I bought a complete power brake set up and brackets so I am confused where I went wrong.

Thanks in advance
88Ironduke
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Old 11-16-2013, 09:53 PM   #2
hugger6933
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Re: Help: Power brake conversion pedal really low

I don't guess you took a measurement from the floor to the petal before you took the truck apart? How far is the brake from the floor now ? It seems that the pushrod it too short. What is the booster combo off of? Is it a truck like yours? These questions may be already asked and answered in your mind just trying to help with fresh eyes without seeing, if you know what I mean. Jim
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Old 11-16-2013, 10:26 PM   #3
88Ironduke
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Re: Help: Power brake conversion pedal really low

Thanks, the booster combo is an aftermarket kit, was listed for a 71/72. The linkage was off of a 71' 4WD. I didn't see where the 4WD makes any difference. I guess my confusion is about the push rod coming from the pedal assembly. Is the input push rod (mounted to the brake pedal) different between trucks? I didn't measure the original assembly but can reinstall but the new set up is obscenely low to the floor.





88
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Old 11-16-2013, 10:58 PM   #4
ole dollor
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Re: Help: Power brake conversion pedal really low

you might also try adjusting your rear brakes, if they are still drums on the rear ,you did not say if your peddle was spongy , adjusting the rear is where you get the peddle height from on disk on the front and drums on the rear...
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Old 11-16-2013, 11:06 PM   #5
88Ironduke
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Re: Help: Power brake conversion pedal really low

Sorry, system is zero on fluid, haven't gotten that far yet. Pedal is down at the floor spring loaded up against the booster/master cylinder assembly.

88
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Old 11-16-2013, 11:50 PM   #6
Lattimer
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Re: Help: Power brake conversion pedal really low

The rod between the pedal and booster is adjustable. You have to pull it out to adjust it (at least I did). You should be able to make it a little longer, but the brake pedal will still be lower than it used to be. Mine was the same way when I installed the booster.

I had the rod from the donor truck as well as the brackets, and still had the same issue. No clue what the donor was, PO threw the parts in the deal when I bought the truck.
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Old 11-17-2013, 06:48 AM   #7
88Ironduke
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Re: Help: Power brake conversion pedal really low

I adjusted the input clevis out but it made very little change on the pedal. Its nice to know I'm not the only person who has seen this.....

I will check everything out today again and see what I can figure out. Worst case I may weld up an adjustable clevis and install is accordingly. When I had the original master cylinder installed the pedal was up high nearly even with the clutch.

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Old 11-17-2013, 07:21 AM   #8
JimKshortstep4x4
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Re: Help: Power brake conversion pedal really low

Original power brake pedal height is approximately 3 3/4" from the floor to the top of the pad. Just slightly higher then the gas pedal.

Jim
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Old 11-17-2013, 08:48 AM   #9
bigmac73
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Re: Help: Power brake conversion pedal really low

what set up did you buy?
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Old 11-17-2013, 09:00 AM   #10
88Ironduke
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Re: Help: Power brake conversion pedal really low

Quote:
Originally Posted by JimKshortstep4x4 View Post
Original power brake pedal height is approximately 3 3/4" from the floor to the top of the pad. Just slightly higher then the gas pedal.

Jim
That is exactly where my brake pedal is from the floor....... I assumed that the pedal would be even with the clutch pedal as it would have been with the original non-power brakes. I think my I.D.10T light is on..... Will look a little more closely this afternoon. Thanks for help on this.


As for the kit, well I didn't purchase it as a complete assembly but everything was researched for 71/72 and everything did bolt as advertised.

Once again thanks for the info provided. The people here are a good group.

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