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 05-30-2020, 11:29 PM   #1
402Bowtie
Registered User
 
402Bowtie's Avatar
 
Join Date: Sep 2003
Location: Denver, CO
Posts: 3,721
HO52 Rear Drum Brakes Adjustment Hole Exists

There are few old threads that people mention having difficulty adjusting the drum brakes on HO52 rear drums. Like many others, I was hoping to find an access hole on the backside that some other drum brake models have for adjusting the star wheel. But the drums on my 72 don't have any access holes on the backside.

From what I have read it seems like many (maybe all) HO52 drums do not have an access hole on the backside of the drum. However, today, after replacing the shoes and guts, I noticed that my 72 does have an access hole on the front of the drum.

Do others have this this hole? Is this common knowledge? I feel like I haven't seen much mention of this hole in the past.
Attached Images
  
402Bowtie is online now   Reply With Quote
Old 05-30-2020, 11:59 PM   #2
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,499
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

I'm glad (and you are lucky) that your drums have that access hole. Mine definitely do not.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 05-31-2020, 12:45 AM   #3
FirstOwner69
Senior Member
 
FirstOwner69's Avatar
 
Join Date: May 2010
Location: Wisconsin & Arizona
Posts: 4,839
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Mine do, and they are the orginals.
Attached Images
 
__________________
Jim
FirstOwner69 is offline   Reply With Quote
Old 06-30-2020, 03:00 PM   #4
Astro-Balls
Registered User
 
Astro-Balls's Avatar
 
Join Date: Feb 2019
Location: Nor Cal
Posts: 822
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Just got new drums for my C20, the drums did NOT come with Adjuster holes, Looks like one of the original drums someone cut and drilled the adjuster hole.
Is it OK to cut and Drill the Drum for the Adjuster Hole??
__________________
1968 C20 Fleetside 396 4sp PS PB AC CST

.
https://www.youtube.com/watch?v=RWK8GgWD4uA
Astro-Balls is offline   Reply With Quote
Old 06-30-2020, 03:14 PM   #5
402Bowtie
Registered User
 
402Bowtie's Avatar
 
Join Date: Sep 2003
Location: Denver, CO
Posts: 3,721
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Quote:
Originally Posted by Astro-Balls View Post
Just got new drums for my C20, the drums did NOT come with Adjuster holes, Looks like one of the original drums someone cut and drilled the adjuster hole.
Is it OK to cut and Drill the Drum for the Adjuster Hole??
I know others have drilled the hole.

The kit I used to replace my drum parts included a few types of plugs...You might consider drilling the hole in a way that you can plug it with something.
402Bowtie is online now   Reply With Quote
Old 06-30-2020, 04:01 PM   #6
americanmusc1e
Senior Member
 
americanmusc1e's Avatar
 
Join Date: Jan 2009
Location: Austin, TX
Posts: 1,079
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Quote:
Originally Posted by Astro-Balls View Post
Just got new drums for my C20, the drums did NOT come with Adjuster holes, Looks like one of the original drums someone cut and drilled the adjuster hole.
Is it OK to cut and Drill the Drum for the Adjuster Hole??
personally I'd drill a hole in the backing plate so you can adjust with the wheel on. I haven't looked at one of those in a while but it should be possible.
__________________
-- Josh

Instagram: @americanmusc1e

OLD SKOOL-- 1970 C10. 454/Th400/3.07 posi Build Thread
FARM TRUCK----1949 Chevrolet 3800 Power Wagon Hauler Build Thread

1999 4wd OBS Tahoe - daily.

DM me if you can't see photos i posted
americanmusc1e is offline   Reply With Quote
Old 06-30-2020, 04:09 PM   #7
toolboxchev
Registered User
 
Join Date: Jul 2015
Location: 2nd left past the stump on a dirt road.
Posts: 2,629
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Quote:
Originally Posted by Astro-Balls View Post
Just got new drums for my C20, the drums did NOT come with Adjuster holes, Looks like one of the original drums someone cut and drilled the adjuster hole.
Is it OK to cut and Drill the Drum for the Adjuster Hole??
I have new Raybesto, and Centric and Wagner stuff laying around most of them do not have the holes, but its in the stamping, or casting.

I wonder if you hit those with a drift pin of some kind do they pop out?

Thinking this is a possibility, knowing manufacturing they would call it non value added processing. And collect the same money for the part.
toolboxchev is offline   Reply With Quote
Old 06-30-2020, 04:33 PM   #8
LockDoc
The Older Generation


 
LockDoc's Avatar
 
Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,332
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Quote:
Originally Posted by toolboxchev View Post
I have new Raybesto, and Centric and Wagner stuff laying around most of them do not have the holes, but its in the stamping, or casting.

I wonder if you hit those with a drift pin of some kind do they pop out?

Thinking this is a possibility, knowing manufacturing they would call it non value added processing. And collect the same money for the part.

I have found that trying to punch them out does not work. All you do is beat the crap out of the drum.

LockDoc
__________________
Leon

Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles

(My Dually Pickup Project Thread)

http://67-72chevytrucks.com/vboard/s...d.php?t=829820

-
LockDoc is offline   Reply With Quote
Old 06-30-2020, 04:38 PM   #9
weim55
Registered User
 
Join Date: Jan 2017
Location: Larkspur, Colorado
Posts: 904
Re: HO52 Rear Drum Brakes Adjustment Hole Exists

Quote:
Originally Posted by toolboxchev View Post
I have new Raybesto, and Centric and Wagner stuff laying around most of them do not have the holes, but its in the stamping, or casting.

I wonder if you hit those with a drift pin of some kind do they pop out?

Thinking this is a possibility, knowing manufacturing they would call it non value added processing. And collect the same money for the part.
I recently went through the rear brakes on my 69 CST 20. Still had the original GM drums. After some careful probing I was able to find the knock out location for the brake adjustment. While it looks like a simple knock out these would not come out easily. Had to heat the knockout area with a torch then punch it through. Upon removal I found both original drums to be junk so they were replaced with the only new drums I could find: Centric brand from rock auto. These do not have knockout holes, I made my own patterning the originals.

Steve weim55 Colorado
Attached Images
  

Last edited by weim55; 06-30-2020 at 04:51 PM.
weim55 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 09:20 PM.


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