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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-13-2016, 12:17 AM   #1
mzsigler
Registered User
 
Join Date: Oct 2016
Location: Memphis, TN
Posts: 96
Is my brake pedal high?

I just picked up this truck as a project. I don't have anything to compare it to, and I haven't driven a truck like this in maybe a decade or more, so I'm just checking before I start chasing a problem that isn't there.

The brake pedal seems insanely high to me. The brakes are also SUPER weak, like, if I stomp the life out of them they will eventually lock up the tires a little, but there's what feels like 12" of very spongy travel first. i drove it back from picking it up leaving like 15 car lengths between me and the nearest car because the brakes were downright scary to me. Also, I found a NAPA receipt for a master cylinder the in the glovebox, so the previous owner was obviously working on the brakes too.

Like I said though, it's been a long time since I drove one of these and my current weekend fun car is a 96 Miata with aftermarket pads, so maybe I'm just not used to 35 year old truck brakes.

Here's a pic of the interior where you can at least kinda see the pedal position. I turned up the exposure to make it visible.



I can take better pics and measure on Tuesday when I'm back at the shop, but I was wondering if anyone can tell me if this is abnormal just based on this picture so I can do some research while I have downtime.

I'm short, 5'6", and I have to like fully bend my knee to raise my leg up high enough to hit the brake pedal. Seems F'ed to me. What do you guys think?
__________________
96 Miata FM 2.5 suspension, roll bar, brakes, hardtop.
82 C10 Turbo LSx build in progress:
http://67-72chevytrucks.com/vboard/s....php?p=7764896
mzsigler is offline   Reply With Quote
Old 11-13-2016, 12:34 AM   #2
rich weyand
Registered User
 
rich weyand's Avatar
 
Join Date: Apr 2014
Location: Bloomington Indiana
Posts: 1,041
Re: Is my brake pedal high?

Hard to tell for sure, but it looks right to me. Brake pedals were much higher back in the day compared to now.

Sounds like when the PO replaced the master cylinder, the lines weren't bled properly. There's a trick to it. Longest line first.
__________________
Rich Weyand

1978 K10 RCSB DD.
rich weyand is offline   Reply With Quote
Old 11-13-2016, 12:37 AM   #3
mzsigler
Registered User
 
Join Date: Oct 2016
Location: Memphis, TN
Posts: 96
Re: Is my brake pedal high?

Quote:
Originally Posted by rich weyand View Post
Hard to tell for sure, but it looks right to me. Brake pedals were much higher back in the day compared to now.

Sounds like when the PO replaced the master cylinder, the lines weren't bled properly. There's a trick to it. Longest line first.
Yeah the photo isn't great, it wasn't at all taken to illustrate the height, I just thought about asking and that's the only photo in which you can even kinda see the pedal height.

I guess I'll get to bleeding and try to remember not to try to heel and toe it
__________________
96 Miata FM 2.5 suspension, roll bar, brakes, hardtop.
82 C10 Turbo LSx build in progress:
http://67-72chevytrucks.com/vboard/s....php?p=7764896
mzsigler is offline   Reply With Quote
Old 11-13-2016, 12:46 AM   #4
nonstop
Registered User
 
Join Date: Dec 2014
Location: Northern California
Posts: 422
Re: Is my brake pedal high?

Does it have power brakes? What does the RPO sticker say for code for brakes? it looks like either the pedal was changed or the truck was originally a 3 on the tree, possibly meaning the truck was originally a low optioned truck with manual brakes. There could be a mix and match of brake parts going on..... causing odd braking
nonstop is offline   Reply With Quote
Old 11-13-2016, 12:51 AM   #5
mzsigler
Registered User
 
Join Date: Oct 2016
Location: Memphis, TN
Posts: 96
Re: Is my brake pedal high?

Quote:
Originally Posted by nonstop View Post
Does it have power brakes? What does the RPO sticker say for code for brakes? it looks like either the pedal was changed or the truck was originally a 3 on the tree, possibly meaning the truck was originally a low optioned truck with manual brakes. There could be a mix and match of brake parts going on..... causing odd braking
__________________
96 Miata FM 2.5 suspension, roll bar, brakes, hardtop.
82 C10 Turbo LSx build in progress:
http://67-72chevytrucks.com/vboard/s....php?p=7764896
mzsigler is offline   Reply With Quote
Old 11-14-2016, 12:59 PM   #6
hatzie
Moderator
 
hatzie's Avatar
 
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 4,977
Re: Is my brake pedal high?

It's a YE9 Silverado optioned truck. It would be very unusual to have three on the tree.
That pedal looks normal.
You should bleed the master then bleed the rest of the system.
I hate the pump the pedal bleeding method because it occasionally leaves small air pockets and if you're not very alert you can run the master cylinder dry.
Some folks like using a mighty vac to bleed the brakes but I've had mixed results with this method.
I'm a fan of pressure bleeders like the Motive Products units that push brake fluid from a tank to the Master and through to the wheels. This is the most consistent method I've found. You can build your own or buy one.
__________________
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.
hatzie is offline   Reply With Quote
Old 11-14-2016, 02:13 PM   #7
Keith Seymore
Registered User
 
Keith Seymore's Avatar
 
Join Date: May 2009
Location: Motor City
Posts: 9,226
Re: Is my brake pedal high?

Quote:
Originally Posted by hatzie View Post
It's a YE9 Silverado optioned truck. It would be very unusual to have three on the tree.
CF321315 = 1982 model year ("C") built in Flint ("F"). My guys probably put the fenders on that truck...



SPID shows MX1, which is the three speed automatic trans. Heritage Center docs indicate a 5600 lb GVW (based on the tire selection) which means Power Brakes J50 (JB3) are standard.

https://www.gmheritagecenter.com/doc...olet-Truck.pdf

Pedal height looks correct to me, too.

K

__________________
Chevrolet Flint Assembly
1979-1986
GM Full Size Truck Engineering
1986 - 2019
Intro from an Old Assembly Guy: http://67-72chevytrucks.com/vboard/s...d.php?t=342926
My Pontiac story: http://forums.maxperformanceinc.com/...d.php?t=560524
Chevelle intro: http://www.superchevy.com/features/s...hevy-chevelle/

Last edited by Keith Seymore; 11-15-2016 at 08:08 AM.
Keith Seymore is offline   Reply With Quote
Old 11-14-2016, 07:14 PM   #8
Dead Parrot
Registered User
 
Join Date: Aug 2012
Location: Oklahoma City, OK
Posts: 2,611
Re: Is my brake pedal high?

Before bleeding, get yourself a throwaway turkey baster and suck all of the old fluid out of the master cylinder and replace with new. That way, when you are done bleeding, you will have replaced most of the old nasty fluid with new fresh fluid.

Another vote for petal height looks correct.

Once you fix the soft brake problem, there is probably some adjustment possible assuming that is a power brake setup. The rod from the petal to the booster should have screw thread setup that will allow some petal height adjustment. Just be sure to make a matching adjustment in your brake light switch. Don't get too wild in lowering the petal. That space between petal and floor comes in handy when you have several hundred pounds of stuff in the bed + the 19' boat in tow.
Dead Parrot is offline   Reply With Quote
Old 11-14-2016, 07:58 PM   #9
cadillac_al
Registered User
 
Join Date: Oct 2013
Location: Maine
Posts: 2,375
Re: Is my brake pedal high?

There is a stopper (?) thingy that the pedal rests on in the up position. It can't go any higher than that.
__________________
76 Chevy K20
76 GMC K15
77 Chevy C10
77 Chevy K10
cadillac_al is offline   Reply With Quote
Old 11-15-2016, 11:31 PM   #10
Shugalou
Registered User
 
Shugalou's Avatar
 
Join Date: Jan 2013
Location: Toronto, ON
Posts: 458
Re: Is my brake pedal high?

I Second Hatzie's recommendation on building a pressure bleeder...He urged me to and it worked out great.

Have you also checked the prop valve is working correctly and that the ebrake cable is adjusted properly?
__________________
Found my dad's old truck
http://67-72chevytrucks.com/vboard/s...d.php?t=563321

Newspaper Article Publishing the quest find my dad's old truck
http://www.theglobeandmail.com/globe...ticle12494281/
Shugalou is offline   Reply With Quote
Old 11-16-2016, 09:27 AM   #11
Keith Seymore
Registered User
 
Keith Seymore's Avatar
 
Join Date: May 2009
Location: Motor City
Posts: 9,226
Re: Is my brake pedal high?

Quote:
Originally Posted by Shugalou View Post
... and that the ebrake cable is adjusted properly?
Or - to expand on that thought - that the rear shoes are adjusted out appropriately?

K
__________________
Chevrolet Flint Assembly
1979-1986
GM Full Size Truck Engineering
1986 - 2019
Intro from an Old Assembly Guy: http://67-72chevytrucks.com/vboard/s...d.php?t=342926
My Pontiac story: http://forums.maxperformanceinc.com/...d.php?t=560524
Chevelle intro: http://www.superchevy.com/features/s...hevy-chevelle/
Keith Seymore is offline   Reply With Quote
Old 11-16-2016, 12:10 PM   #12
mzsigler
Registered User
 
Join Date: Oct 2016
Location: Memphis, TN
Posts: 96
Re: Is my brake pedal high?

Quote:
Originally Posted by hatzie View Post
It's a YE9 Silverado optioned truck. It would be very unusual to have three on the tree.
That pedal looks normal.
You should bleed the master then bleed the rest of the system.
I hate the pump the pedal bleeding method because it occasionally leaves small air pockets and if you're not very alert you can run the master cylinder dry.
Some folks like using a mighty vac to bleed the brakes but I've had mixed results with this method.
I'm a fan of pressure bleeders like the Motive Products units that push brake fluid from a tank to the Master and through to the wheels. This is the most consistent method I've found. You can build your own or buy one.
Yeah I'll likely go with that method, the brakes need a full overhaul. I'm waiting for two more packages from Western Chassis, might as well do it while I'm installing the lowering kit.
__________________
96 Miata FM 2.5 suspension, roll bar, brakes, hardtop.
82 C10 Turbo LSx build in progress:
http://67-72chevytrucks.com/vboard/s....php?p=7764896
mzsigler is offline   Reply With Quote
Old 11-16-2016, 01:10 PM   #13
mzsigler
Registered User
 
Join Date: Oct 2016
Location: Memphis, TN
Posts: 96
Re: Is my brake pedal high?

And you guys are absolutely right btw, I'm at my shop with the truck and the pedal isn't near as high as I remembered, just spongy. I'll dig into the brakes this weekend.
__________________
96 Miata FM 2.5 suspension, roll bar, brakes, hardtop.
82 C10 Turbo LSx build in progress:
http://67-72chevytrucks.com/vboard/s....php?p=7764896
mzsigler 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 07:24 PM.


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