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 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-15-2017, 10:38 AM   #1
cjoenny89
Registered User
 
cjoenny89's Avatar
 
Join Date: Apr 2015
Location: St. Charles, Michigan
Posts: 214
any tips before I start Front brakes? 68 C20?

I am looking for tips before I start replacing the brake cylinders on the front of my 68 C20. I after replacing the rear brake cylinder and master cylinder I had to bleed the fronts and well I could not bleed the fronts nothing came out even with the bleeder screw out. I have new rubber hoses to put on and new wheel cylinders. Does anyone have any tips on getting the drums off? and any tips on changing the wheel cylinders? I am banking on the brakes are good If not back to the store. any tips would be great
Chad
__________________
1968 Chevy C20 3OTT 327 V8
cjoenny89 is offline   Reply With Quote
Old 06-15-2017, 11:26 AM   #2
harpo231
Registered User
 
harpo231's Avatar
 
Join Date: Nov 2014
Location: Lincoln City DE
Posts: 1,292
Re: any tips before I start Front brakes? 68 C20?

Back the adjustment off and drums will come off easier. Sounds like you need those cylinders and hoses !
harpo231 is offline   Reply With Quote
Old 06-15-2017, 01:03 PM   #3
jocko
Senior Member
 
jocko's Avatar
 
Join Date: Oct 2009
Location: Godley, TX
Posts: 17,934
Re: any tips before I start Front brakes? 68 C20?

Take a digi camera pic after the drum is off for ref.
jocko is offline   Reply With Quote
Old 06-15-2017, 01:28 PM   #4
cjoenny89
Registered User
 
cjoenny89's Avatar
 
Join Date: Apr 2015
Location: St. Charles, Michigan
Posts: 214
Re: any tips before I start Front brakes? 68 C20?

thanks for the tips
__________________
1968 Chevy C20 3OTT 327 V8
cjoenny89 is offline   Reply With Quote
Old 06-15-2017, 03:48 PM   #5
FirstOwner69
Senior Member
 
FirstOwner69's Avatar
 
Join Date: May 2010
Location: Wisconsin & Arizona
Posts: 4,839
Wink Re: any tips before I start Front brakes? 68 C20?

Quote:
Originally Posted by jocko View Post
Take a digi camera pic after the drum is off for ref.
What Jocko said!
Attached Images
  
FirstOwner69 is offline   Reply With Quote
Old 06-15-2017, 03:59 PM   #6
cjoenny89
Registered User
 
cjoenny89's Avatar
 
Join Date: Apr 2015
Location: St. Charles, Michigan
Posts: 214
Re: any tips before I start Front brakes? 68 C20?

thanks for the pics!
Ok so when I put them on just a slight drag and then let the adjuster do its thing?
I will make sure the adjuster is free!
__________________
1968 Chevy C20 3OTT 327 V8
cjoenny89 is offline   Reply With Quote
Old 06-15-2017, 05:07 PM   #7
FirstOwner69
Senior Member
 
FirstOwner69's Avatar
 
Join Date: May 2010
Location: Wisconsin & Arizona
Posts: 4,839
Re: any tips before I start Front brakes? 68 C20?

If you remove the hub with the drum, torque the bearing to 40 ft-lbs while turning the drum. Then back the nut off 1/3 turn. if the hole for the cotter pin dies not align with a slot in the nut, back off just enough to allow the cotter pin to pass through the hole. Use a new cotter pin. This is how the service manual says to adjust the bearing.

Note that the shorter shoe is toward the front.

I always adjust them to get a slight drag and apply the brakes which helps center the shoes. Then, I adjust them until they are snug and back the adjuster off about 1/2 turn. You should still hear some rubbing, probably not constant, when the drum is turned.

Here's a clean/after picture of the right front where it's easier to see things
Attached Images
 

Last edited by FirstOwner69; 06-16-2017 at 10:58 AM.
FirstOwner69 is offline   Reply With Quote
Old 06-16-2017, 01:58 AM   #8
mike16
Registered User
 
Join Date: Dec 2009
Location: bisbee, arizona
Posts: 1,529
Re: any tips before I start Front brakes? 68 C20?

take picture, somebody already did but take lots of pictures.

there is a piston inside the distributor block located just below the master cylinder. when one side of the system fails that piston moves over and blocks the flow of fluid so no more than an absolute minimum is pumped out.

that piston needs to be re centered and held in the center position while both front and rear brake systems are flushed

fix that and flush the whole system, front and rear, befor removing the master cylinder or any wheel cylinder

If you dont.. you will be pumping old dirty fluid into your newly rebuilt wheel cylinders.

flush the system first, then take off various components, one at a time , rebuild it reinstall it before going on to the next component. Always think in terms of NOT pumping dirty fluid into your clean newly overhauled system.
mike16 is offline   Reply With Quote
Old 06-19-2017, 09:44 AM   #9
cjoenny89
Registered User
 
cjoenny89's Avatar
 
Join Date: Apr 2015
Location: St. Charles, Michigan
Posts: 214
Re: any tips before I start Front brakes? 68 C20?

Update
everything went fairly smooth replacing the front brake flex hoses and brake cylinders.
I only took apart enough to get the brake cylinders apart so I know knowing is put together wrong. Sprayed it all down with brake cleaner. Thought I adjusted the front drums with just a little drag on the drum turning by hand. drove it 1/2 mile it was perfect.
went to go for another ride and the front brakes were grabbing as soon as you push the clutch in it felt you were pushing the brake pedal. Drove it in the garage jacked it up and I could not turn the front wheels. Why would the fronts start out so nice then tighten up so bad I couldn't turn them? The back drivers rear did that to me also last week. It got so tight that it was smoking. Why are the self adjusters tightening up? Do I need to readjust now that I have all the air out of the lines and the brake cylinders bleed?
and just before you ask the adjusters are correct they never left the wheel they were on and each of them adjusted easily by hand. I have drove the truck last summer and never had the brakes do this.
I have replaced recently master cylinder (bench bleed) front and rear brake cylinders and front flex hoses.
Any suggestions?
Thanks
__________________
1968 Chevy C20 3OTT 327 V8
cjoenny89 is offline   Reply With Quote
Reply

Bookmarks


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 03:44 PM.


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