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Old 03-14-2017, 09:51 PM   #1
mattfrediani
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Brake booster issue- Dangerous please Help

I had a hot rod shop install all new braking system on my 1970 4wd long bed
I put a dana 44 under it with new slotted rotors and calipers. I did not want to do the brakes so I farmed it out to a good shop. I asked if they cold mount the new brake booster level so it did not look funny. everything was great for about 250 miles. the other day my pedal after i warmed it up was solid as a rock it was binding on something. after i pushed on the pedal hard it gave way to normal.
I then carefully test drove the truck and everything was fine. I took truck out today for another test run and the same thing happened. I pushed the pedal as hard as i could to stop the truck and something went bang and then it was fine again. I popped the hood and found the upper clevis pin that mounts the linkage from the pedal to the brake booster rod was almost falling out due to the half snap ring was gone or broken off to lock the clevis pin in place. I ordered a new clevis pin with a hole so I can install a cotter pin so it stays secure. I also ordered the clevis pin so theres not much slop.. I think the half snap ring came loose and when I hit the brakes the pin may have stuck out and binded in the hole on the side of the booster mount that bolts to the fire wall... My question is is it possible that mounting the brake booster level rather then slanted (shimmed) caused this to happen internally in the booster? or was it most likely the sloppy clevis pin that the snap ring fell off binded? any help or suggestions welcome!
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Old 03-14-2017, 10:30 PM   #2
kwmech
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Re: Brake booster issue- Dangerous please Help

Sounds like you may have figured it out and shouldn't have any future issues. But, having those straight lines from the master cyl like that could lead (in the future) to issues. There is a reason that the factory puts a couple of loops in the line. Frame to body flex.
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Old 03-14-2017, 10:34 PM   #3
mattfrediani
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Re: Brake booster issue- Dangerous please Help

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unsure of your question but i have that same pulley setup they said it wouldn't work with power steering what did you do to make it work
I just bolted it all up? My power steering pump is in the same place I just got a borgeson steering pump and put a billet pulley on it. no problems so far- it all lined up just fine
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Old 03-14-2017, 10:36 PM   #4
mattfrediani
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Re: Brake booster issue- Dangerous please Help

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Sounds like you may have figured it out and shouldn't have any future issues. But, having those straight lines from the master cyl like that could lead (in the future) to issues. There is a reason that the factory puts a couple of loops in the line. Frame to body flex.
This truck will never see off road so Im hoping I can keep it the way it is with the brake lines. do you know of any soft steel braided lines I can use instead ?
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Old 03-15-2017, 10:12 AM   #5
davepl
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Re: Brake booster issue- Dangerous please Help

The coils are there for three reasons that I know of, the third I'm not sure about:

a) Body flex
b) Accident - be able to take minor dislocation without severing the lines
c) Cooling - supposedly helps trap boild/overheated brake fluid and cools it

I wouldn't worry about the cooling part even if it's true.
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Old 03-15-2017, 12:53 PM   #6
BrianG
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Re: Brake booster issue- Dangerous please Help

I can not believe that any reputable shop would actually run brake lines that way. Those should be changed for the reasons stated above.
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Old 03-15-2017, 03:50 PM   #7
bs46488
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Re: Brake booster issue- Dangerous please Help

That is an interesting setup on the brake lines. Is there no proportional valve needed?

What happens if that belt gets torn up and thrown off the pulley, would the line get damaged?

Off roading or not, you are going to see a lot of vibration from just driving it.
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Old 03-15-2017, 03:58 PM   #8
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Re: Brake booster issue- Dangerous please Help

That shop dont know Jack.
Undo all they did before it kills someone.
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Old 03-15-2017, 05:46 PM   #9
custom10nut
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Re: Brake booster issue- Dangerous please Help

X2
Search the forum and you'll find a thread on how to install the power brake setup correctly.
Your current setup ain't it
I can't believe a professional shop allowed that.
You need the lines routed along the frame and up to a disc/drum pro portioning block, or even an adjustable valve.
Go back to that shop and have them either do it correctly, or you get your money back.
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Old 03-15-2017, 06:21 PM   #10
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Re: Brake booster issue- Dangerous please Help

It looks like the proportioning valve is there up by the radiator. Still would change the routing, put the valve by the booster and the the coils or bends between the proportion valve and frame. I'd have them redo it correctly. From what I see of the rest of the engine compartment I'm impressed. Don't let the brakes distract from what else is very nice.
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Old 03-16-2017, 01:37 PM   #11
70STOVEBOLT
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Re: Brake booster issue- Dangerous please Help

I don't know if you have inspections in your state, but that would not pass a DOT inspection IMO.
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Old 03-16-2017, 01:44 PM   #12
Keith Seymore
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Re: Brake booster issue- Dangerous please Help

Quote:
Originally Posted by davepl View Post
The coils are there for three reasons that I know of, the third I'm not sure about:

a) Body flex
b) Accident - be able to take minor dislocation without severing the lines
c) Cooling - supposedly helps trap boild/overheated brake fluid and cools it

I wouldn't worry about the cooling part even if it's true.
d) Assembly - the coils allow the assembly line operator to quickly "accordion" the lines up or down or rotate to start the fittings into the master cylinder.

K
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Old 03-16-2017, 01:49 PM   #13
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Re: Brake booster issue- Dangerous please Help

These trucks don't have prop valves from the factory. Just a distribution block. That setup is wonky as all get out. Not sure how reputable that shop is. Looks like the too the easy way out to not route the lines through the stock location along the rear of the front crossmember.

Also the angle of the whole assembly was there for a reason. But maybe it's not that big of a deal.

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