The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1960 - 1966 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-13-2018, 04:30 PM   #1
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
break peddles peddle question

I know that the brake peddles on this trucks are vary high but mine does not seem to even enguage the brakes until the peddle is about half way down.
I have front cpp discs and rear drums with a captonfab booster bracket. they stop the truck fine but it is a little bit of a pain. I have the correct proportioning valve for a disk drum setup. Will shortening the rod and lowering the peddle help? Or will I just be stepping around the problem?
forestb is offline   Reply With Quote
Old 03-13-2018, 06:08 PM   #2
TheBrewery
Registered User
 
TheBrewery's Avatar
 
Join Date: Aug 2017
Location: Memphis, TN
Posts: 79
Re: break peddles peddle question

I'm chasing down brake problems too

If you shorten the pedal won't that just put the effective area out of reach? Have you checked the clearance between the booster and the master? It should be 0.25 - 0.75 mm of clearance, but if there is more it will cause what you are talking about. There also could be air in the setup that is compressing before the fluid moves. Have you tried rebleeding?
__________________
Mike
1960 C10 Short Step 235 w/ 3 on the tree
1999 Mazda Miata <- Track Car
2016 Chevrolet Colorado z71
2016 Chevrolet Traverse - Wifes Car
2014 Honda CBR500R <- Also A Dust Collector
2009 Suzuki GSXR600 <- Stolen
TheBrewery is offline   Reply With Quote
Old 03-13-2018, 06:28 PM   #3
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

Do you mean clearance from the push rod or between the surfaces that come together when it is bolted together. No I have not tried rebleeding but when I took it to the mechanic to check them out he said they were fine. Maybe it is low on fluid.

I wonder if there is a way test to see when I start to get brake pressure maybe the rod is to short.

Quote:
Originally Posted by TheBrewery View Post
I'm chasing down brake problems too

If you shorten the pedal won't that just put the effective area out of reach? Have you checked the clearance between the booster and the master? It should be 0.25 - 0.75 mm of clearance, but if there is more it will cause what you are talking about. There also could be air in the setup that is compressing before the fluid moves. Have you tried rebleeding?
forestb is offline   Reply With Quote
Old 03-13-2018, 09:06 PM   #4
TheBrewery
Registered User
 
TheBrewery's Avatar
 
Join Date: Aug 2017
Location: Memphis, TN
Posts: 79
Re: break peddles peddle question

Quote:
Originally Posted by forestb View Post
Do you mean clearance from the push rod or between the surfaces that come together when it is bolted together. No I have not tried rebleeding but when I took it to the mechanic to check them out he said they were fine. Maybe it is low on fluid.

I wonder if there is a way test to see when I start to get brake pressure maybe the rod is to short.
So check out this video, https://youtu.be/rYYzPIGoxfY?t=1915, It shows you how to measure the booster pin and MC piston to ensure they are "set" correctly.
__________________
Mike
1960 C10 Short Step 235 w/ 3 on the tree
1999 Mazda Miata <- Track Car
2016 Chevrolet Colorado z71
2016 Chevrolet Traverse - Wifes Car
2014 Honda CBR500R <- Also A Dust Collector
2009 Suzuki GSXR600 <- Stolen
TheBrewery is offline   Reply With Quote
Old 03-13-2018, 09:27 PM   #5
jayoldschool
Moderator
 
Join Date: Dec 2012
Location: ON, Canada
Posts: 2,148
Re: break peddles peddle question

Quote:
Originally Posted by forestb View Post
I know that the brake peddles on this trucks are vary high but mine does not seem to even enguage the brakes until the peddle is about half way down.
I have front cpp discs and rear drums with a captonfab booster bracket. they stop the truck fine but it is a little bit of a pain. I have the correct proportioning valve for a disk drum setup. Will shortening the rod and lowering the peddle help? Or will I just be stepping around the problem?
Do you have the correct DISC drum master as well?
jayoldschool is offline   Reply With Quote
Old 03-13-2018, 09:45 PM   #6
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

I believe so. It is a dual cylinder.
forestb is offline   Reply With Quote
Old 03-13-2018, 09:54 PM   #7
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

here is the best photo I have of it.
Attached Images
 
forestb is offline   Reply With Quote
Old 03-13-2018, 11:16 PM   #8
TheBrewery
Registered User
 
TheBrewery's Avatar
 
Join Date: Aug 2017
Location: Memphis, TN
Posts: 79
Re: break peddles peddle question

That looks like the corvette style dual pot, it is equal but you have a proportioning valve so you should be fine there.
__________________
Mike
1960 C10 Short Step 235 w/ 3 on the tree
1999 Mazda Miata <- Track Car
2016 Chevrolet Colorado z71
2016 Chevrolet Traverse - Wifes Car
2014 Honda CBR500R <- Also A Dust Collector
2009 Suzuki GSXR600 <- Stolen
TheBrewery is offline   Reply With Quote
Old 03-14-2018, 12:25 AM   #9
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 23,246
Re: break peddles peddle question

Is your booster pushrod in the original hole in the pedal or did you drill a new hole 1" lower?
__________________
Power Steering Box Adapter Plates For Sale HERE
Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE
Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE
Hydroboost Mounting Plates HERE
Captainfab is offline   Reply With Quote
Old 03-14-2018, 10:38 AM   #10
chevy_mike
Never Ending Projects
 
chevy_mike's Avatar
 
Join Date: Jul 2006
Location: San Diego, CA
Posts: 3,836
Re: break peddles peddle question

Quote:
Originally Posted by Captainfab View Post
Is your booster pushrod in the original hole in the pedal or did you drill a new hole 1" lower?
Yes, what he said. This is one of the most common mistakes people make. The pedal ratio is different between manual and power brakes. Power needs to be 1" lower than where a manual pedal would hook too. If not, your pedal will engage way too low and the brakes tend to be touchy.

Buddy did his truck conversion and didn't believe me. Had the same problem of low pedal engagement and being touchy. Finally drilled a hole 1" lower and the brakes were perfect.
__________________
.
1965 C10 Panel, Tiki Express http://www.67-72chevytrucks.com/vboa...d.php?t=506580 SOLD
1968 Chevy C10, Long, Fleetside, Hot Rod Hauler http://67-72chevytrucks.com/vboard/s...d.php?t=313233 SOLD
1965 Chevy C10, Long, Fleetside, Hot Rod C10 http://67-72chevytrucks.com/vboard/s...d.php?t=415702 SOLD


We were given two ears and one mouth for a reason... listen twice as much and speak half as often...
chevy_mike is offline   Reply With Quote
Old 03-14-2018, 10:52 AM   #11
TheBrewery
Registered User
 
TheBrewery's Avatar
 
Join Date: Aug 2017
Location: Memphis, TN
Posts: 79
Re: break peddles peddle question

Quote:
Originally Posted by chevy_mike View Post
Yes, what he said. This is one of the most common mistakes people make. The pedal ratio is different between manual and power brakes. Power needs to be 1" lower than where a manual pedal would hook too. If not, your pedal will engage way too low and the brakes tend to be touchy.

Buddy did his truck conversion and didn't believe me. Had the same problem of low pedal engagement and being touchy. Finally drilled a hole 1" lower and the brakes were perfect.
Does this apply to the 1960?
__________________
Mike
1960 C10 Short Step 235 w/ 3 on the tree
1999 Mazda Miata <- Track Car
2016 Chevrolet Colorado z71
2016 Chevrolet Traverse - Wifes Car
2014 Honda CBR500R <- Also A Dust Collector
2009 Suzuki GSXR600 <- Stolen
TheBrewery is offline   Reply With Quote
Old 03-14-2018, 11:29 AM   #12
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

I have heard of that but never done it. I should give it a try.
forestb is offline   Reply With Quote
Old 03-14-2018, 03:36 PM   #13
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: break peddles peddle question

Brake pedal ratio - https://techtalk.mpbrakes.com/how-to...ng-pedal-ratio
The Rocknrod is offline   Reply With Quote
Old 03-14-2018, 03:49 PM   #14
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

Thanks. This is always something I have thought about doing but never got around to.
forestb is offline   Reply With Quote
Old 03-14-2018, 06:01 PM   #15
verdell
Registered User
 
verdell's Avatar
 
Join Date: Feb 2013
Location: Columbus, MS
Posts: 433
Re: break peddles peddle question

Quote:
Originally Posted by TheBrewery View Post
Does this apply to the 1960?
Yes, it does apply to the '60. Helped my brakes quite a bit.
verdell is offline   Reply With Quote
Old 03-14-2018, 09:52 PM   #16
TheBrewery
Registered User
 
TheBrewery's Avatar
 
Join Date: Aug 2017
Location: Memphis, TN
Posts: 79
Re: break peddles peddle question

Quote:
Originally Posted by verdell View Post
Yes, it does apply to the '60. Helped my brakes quite a bit.
Sorry to Hijack the thread, I am using Captinfab's bracket, I did drill a hole for the clutch master but not the booster. I don't think the bracket would fit any lower...
__________________
Mike
1960 C10 Short Step 235 w/ 3 on the tree
1999 Mazda Miata <- Track Car
2016 Chevrolet Colorado z71
2016 Chevrolet Traverse - Wifes Car
2014 Honda CBR500R <- Also A Dust Collector
2009 Suzuki GSXR600 <- Stolen
TheBrewery is offline   Reply With Quote
Old 04-02-2018, 04:27 PM   #17
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

So i lowered the hole but have not gotten a chance to drive it yet. But what I was wondering while I was laying on my seat pushing the break peddle down with my hand I heard what sounded like air coming out of where the rod comes out of the booster. But it might just be air being pushed out of the rubber cup that covers where the rod goes into the booster. Is this normal?
forestb is offline   Reply With Quote
Old 04-02-2018, 05:24 PM   #18
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: break peddles peddle question

While the truck is running? or off?
The Rocknrod is offline   Reply With Quote
Old 04-02-2018, 05:37 PM   #19
forestb
Registered User
 
forestb's Avatar
 
Join Date: Jan 2009
Location: Burbank, CA
Posts: 3,581
Re: break peddles peddle question

while running
forestb is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:52 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com