Brake question (not bleed order!) Help!
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Brake question (not bleed order!) Help!
Ever since I bought this car, I've had excessive (~6 inches) pedal travel before the brakes even began to catch and I got any pedal feel at all. Once I was past that point, they were always fine though ... good'n strong. Anyhow, I figured I just needed a new master cylinder ... prob. just blowing past the first seal right? Errrr ... no
I just pulled off the MC, and it looked relatively new. There was no leakage into the booster hole. The bore was clean. The seals were all in good shape, etc.
Sooooo I get in the car, hit the brake pedal, and my partner in crime noticed that the booster rod wasn't even moving until I got past my 6 inches of dead pedal. That can't be right. :confused: Everything appeared to be in order under the dash as far as the pedal to rod linkage. So I have no idea right now. Do I just need to do a LOT of adjustment on the pedal, or did someone install the wrong vacuum booster, or what?
TIA! :flag
[Modified by wcsinx, 12:32 AM 4/1/2004]
I just pulled off the MC, and it looked relatively new. There was no leakage into the booster hole. The bore was clean. The seals were all in good shape, etc.
Sooooo I get in the car, hit the brake pedal, and my partner in crime noticed that the booster rod wasn't even moving until I got past my 6 inches of dead pedal. That can't be right. :confused: Everything appeared to be in order under the dash as far as the pedal to rod linkage. So I have no idea right now. Do I just need to do a LOT of adjustment on the pedal, or did someone install the wrong vacuum booster, or what?
TIA! :flag
[Modified by wcsinx, 12:32 AM 4/1/2004]
Thread Starter
Team Owner
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Re: Brake question (78 Vette)
You may be right about the booster.
That rod should move as soon as you hit the pedal.
That rod should move as soon as you hit the pedal.
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From: Lenoir City Tennessee
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Re: Brake question (wcsinx)
Could it be that maybe someone added a booster to a non PB car. I think there is a difference in the manual and power brake master cylinders. Hopefully someone will chime in and back me on this one.
Hello....anyone....hello
Hello....anyone....hello
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Re: Brake question (Eddie 70)
Could it be that maybe someone added a booster to a non PB car. I think there is a difference in the manual and power brake master cylinders. Hopefully someone will chime in and back me on this one.
Hello....anyone....hello
Hello....anyone....hello
Yeah, the MC is definitely different for manual and power brakes, but that should not affect the booster rod travel. :confused:
[Modified by wcsinx, 2:19 PM 4/1/2004]
Thread Starter
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Re: Brake question (GDaina)
Just finished working on a 67 GTO, the 67 had an adjustable rod travel...can the vette's rod be adjusted?
I'll post some pictures this weekend if I can't figure out what's going on here.
Sooooooo :confused:
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From: St Petersburg FL
St. Jude Donor '07,'13
Re: Brake question (wcsinx)
There is a possibility of 2 different master cyl's. One has a shallow hole in the piston the other has a deep hole. Remove the master cyl. and push the rod all the way into the booster. if it goes back past the face then you need the shallow piston. if it stick's out about 1" then you need the deep piston.
The wrong master will cause this problum! :)
The wrong master will cause this problum! :)
Thread Starter
Team Owner
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Re: Brake question (VBP)
There is a possibility of 2 different master cyl's. One has a shallow hole in the piston the other has a deep hole. Remove the master cyl. and push the rod all the way into the booster. if it goes back past the face then you need the shallow piston. if it stick's out about 1" then you need the deep piston.
The wrong master will cause this problum! :)
The wrong master will cause this problum! :)
To clarify, the rod coming out of the booster which goes to the MC does not move until I push the pedal past ~6" of slack travel. So this says to me that the slack is somewhere between the pedal and the firewall side of the booster. Am I thinking correctly?
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From: In Dreams There Is Truth Ohio
Re: Brake question (wcsinx)
You will be surprised how little adjustment will take up the slack...same thing on the GTO, pedal went to the floor, and a 3/4" adjustment in the travel fixed it. I would try adjusting the travel first before pulling appart the MC
Thread Starter
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Re: Brake question (GDaina)
You will be surprised how little adjustment will take up the slack...same thing on the GTO, pedal went to the floor, and a 3/4" adjustment in the travel fixed it.
I would try adjusting the travel first before pulling appart the MC
