Author Topic: Brake picture needed  (Read 10111 times)

Offline zieg85

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Brake picture needed
« on: August 08, 2015, 07:00:20 PM »
Does anyone have a picture of the rear brakes on a 14 bolt FF obviously with the drum off.  I need to know what the self adjusters look like so I can attempt to depress and back off the adjustment.  Thanks in advance.
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Irish_Alley

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Re: Brake picture needed
« Reply #1 on: August 08, 2015, 07:24:40 PM »

help?
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline zieg85

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Re: Brake picture needed
« Reply #2 on: August 08, 2015, 07:31:35 PM »
It is if that is a 14 bolt FF
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Irish_Alley

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Re: Brake picture needed
« Reply #3 on: August 08, 2015, 07:49:43 PM »
um dually i think idk i new at this stuff
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Irish_Alley

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Re: Brake picture needed
« Reply #4 on: August 08, 2015, 07:59:16 PM »

14 bolt ff
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Irish_Alley

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Re: Brake picture needed
« Reply #5 on: August 08, 2015, 08:02:26 PM »

another 14 bolt. idk what the difference is
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline zieg85

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Re: Brake picture needed
« Reply #6 on: August 08, 2015, 08:15:45 PM »
THANKS TIM, that is what I needed!!!
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline Irish_Alley

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Re: Brake picture needed
« Reply #7 on: August 08, 2015, 08:16:30 PM »
lol no problem
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Greybeard

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Re: Brake picture needed
« Reply #8 on: August 09, 2015, 11:37:45 AM »
They are easy enough, just insert a skinning poking device such as a long skinny screwdriver and push the plate away from the star wheel, turn it (the starwheel) in the appropriate direction with a flat blade, (but you already knew that I suppose). A small flashlight should give you enough of a view inside to see which way that is. Righty tighty isn't necessarily appropriate here. :*)
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Offline Dr_Snooz

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Re: Brake picture needed
« Reply #9 on: August 17, 2015, 01:52:47 PM »
Can someone provide some clarity as to how to adjust the brakes properly? The GM manual says to tighten the adjusters until the wheel can barely be turned by hand, then back off "33 notches." The problem is that if you are holding the plate away from the adjuster, there's no way to count notches? Is it just a best guess kind of thing or is there a good way to do this that I'm missing?
1986 GMC C-2500 Crew Cab, 7.4L, TH400 -- RIP Chester

1989 Chevy Suburban V-2500, 5.7L, TH400

1990 Chevy C-3500 Ext. Cab, 7.4L, 3L80

Offline ehjorten

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Re: Brake picture needed
« Reply #10 on: August 17, 2015, 02:11:21 PM »
I have never heard the '33 notches' thing.  You adjust the star-wheel for a slight drag on the drum.  Rotate the drum occassionally as you rotate the star-wheel.  You can feel and hear the slight drag.  It is just for an initial adjustment.  After that the drum brakes self-adjust whenever you backup and hit the brakes.  If your rig is quiet enough you can usually hear the ratcheting sound.  You do have to brake with a little effort, not just a leisurely, light reverse stop.
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6

Offline bd

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Re: Brake picture needed
« Reply #11 on: August 17, 2015, 04:49:02 PM »
Can someone provide some clarity as to how to adjust the brakes properly? The GM manual says to tighten the adjusters until the wheel can barely be turned by hand, then back off "33 notches." The problem is that if you are holding the plate away from the adjuster, there's no way to count notches? Is it just a best guess kind of thing or is there a good way to do this that I'm missing?

The '33 notches' thing yields an inconsistent result between vehicles.  The following method generally applies to domestic vehicles with auto-adjusting drum brakes.

Release the park brake.  Never adjust the park brake before adjusting an associated drum brake.

If there isn't an adjustment window in the backing plate, reach through the adjustment knockout in the drum (see image - you may need to remove the knockout with a hammer and punch).  Adjust the star wheel until the brake is too tight to spin the drum by hand.  This centers the shoes in the drum and firmly seats them against the anchor pin.  If adjusting through the backing plate, insert a thin cabinet screwdriver through the adjustment window to push the adjuster arm away from the star wheel.  If adjusting through the drum knockout, insert a small hooked tool through the adjustment window in the drum to catch the adjuster arm and pull it toward you to disengage the arm from the star wheel.  Use the brake spoon to back off the star wheel roughly twice the number of "clicks" that the diameter of the drum is in inches (e.g., 22 clicks for a 11" drum) to achieve a base adjustment.

To get the "feel" of one click, use the spoon to adjust the star one 'click' tighter.  Do it again several times.  To back off that number of 'clicks,' move the spoon in reverse the same distance, the same number of times.

As a final adjustment spin the drum by hand and check for a slight drag.  If the drums aren't perfectly round, they may alternately tighten up and then rotate freely.  Loosen or tighten the adjustment for an average very slight drag on the drum.  Firmly apply the brakes with the pedal and then recheck the drag on the drums.  When you're done, both sides should be adjusted about the same number of clicks.

To augment what ehjorten posted regarding self-adjusters, for self-adjustment to be uniform wheel-to-wheel, brakes need to be firmly applied while backing in a straight line.  Proper adjustment is achieved while backing, because of the direction of rotation of the drum, forcing the secondary shoe into the primary shoe through the adjuster and the primary shoe onto the anchor pin, which in turn results in the greatest sweep of the adjuster arm across its star wheel.  Backing straight (or backing left and right, on average, similarly) maintains even adjustment from side-to-side.  But, habitually backing either left or right, such as always backing out of a steep driveway in the same direction, can result in one brake adjusting tighter than its axle mate.

Edit: added image and clarification
« Last Edit: August 26, 2015, 09:54:40 AM by bd »
Rich
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Offline Greybeard

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Re: Brake picture needed
« Reply #12 on: August 24, 2015, 06:06:44 PM »
Good info bd. I completely glossed over the "pull the adjuster arm away part" when I said push... Yep, sometimes I are a dumbox.  ???

I've never seen or heard of the '33 notches either'. I did it the really difficult way I guess, I pulled  8) the arm just enough so it would slide over the notches enough to feel each one. However, in the end I stopped worrying about it at all and just tightened them tight, and used a flashlight to peer in as I was loosening them counting the teeth as they went by the arm. It wasn't easy because I had to have my tongue in just the right spot between my teeth to get one eyeball into position while letting dirt and rust particles penetrate my ear canal to do that.  ;) Young and dumb back then. But in my defense, we didn't have all the fancy tools and gadgetry that's available today, or I couldn't afford any of it. I adjusted (and changed) brakes with a small and a large flat blade screwdriver back then along with a normal lineman's pliers and a bunch of swearing and blood.   
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Offline Dr_Snooz

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Re: Brake picture needed
« Reply #13 on: August 24, 2015, 09:27:54 PM »
Thanks guys. Good stuff!
1986 GMC C-2500 Crew Cab, 7.4L, TH400 -- RIP Chester

1989 Chevy Suburban V-2500, 5.7L, TH400

1990 Chevy C-3500 Ext. Cab, 7.4L, 3L80

Offline roundhouse

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Re: Brake picture needed
« Reply #14 on: August 26, 2015, 06:15:10 AM »
The 14 bolt on my truck had the adjustment slots on top
We had to drill a slot on the bottom to reach in and back the adjustment off so we could remove the drum


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