#1  
Old 09-14-2021, 06:35 PM
Terry M. Hunt Terry M. Hunt is offline
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Default 66 GTO front drum brakes

I’m working through the restoration of my convertible frame. Everything has been cleaned, powder coated or painted, and reassembly with new parts is under way. Finishing up the front brakes today and encountered an issue I have not seen while doing several brake jobs over the past 40+ years. Slid the passenger side drum onto the hub and proceeded to adjust the shoes for a slight drag when spinning the drum by hand. The drum was quite tight and was not easy to spin. I pulled the drum back off so I could turn the star wheel and contract the shoes a little bit. I was only able to turn the wheel about a turn and a half before it was fully contracted. Put the drum back on and gave it a spin. Still has considerable drag and seems to encounter a high spot on shoes as it rotates, producing a stick point that I have to push it past. I’ve read various articles about arcing brake shoes. The Wagner shoes I’m using p/n z246r state on the box “precision ground radius ensures optimum fit with drums”, but I wasn’t born yesterday so I’m not usually real impressed with advertising claims. I can probably spin the drum enough times to create a witness mark on the shoe or shoes that are producing the sticking point, but not sure what to do then. I’ve never had this problem before and always had enough adjustment to wind up with just a slight drag when spinning the drum. What ideas do you guys have for me in this issue?

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  #2  
Old 09-14-2021, 06:42 PM
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ZeGermanHam ZeGermanHam is offline
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Do you have your old brake shoes to compare to the new parts?

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  #3  
Old 09-14-2021, 06:50 PM
Terry M. Hunt Terry M. Hunt is offline
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Default 66 GTO front drum brakes

Yes, still have old shoes. Good idea to compare these to my new shoes.

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Old 09-15-2021, 08:19 AM
gto4evr gto4evr is offline
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you made the comment "powder coat"...did the backing plates get powder coated? if so, possibly the coating's too thick on the pivot point at the top which could spread the shoes out up there. we have issues at work on parts that get too much coating in similar mounting situations that kill the spacing tolerances on assemblies. just a thought.

  #5  
Old 09-15-2021, 05:39 PM
android 211 android 211 is offline
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If there is a sticking point then the drums aren't perfectly round inside. Have them turned once. I would especially suspect this if the drums are new and from off shore.

  #6  
Old 09-16-2021, 07:38 PM
Terry M. Hunt Terry M. Hunt is offline
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Default 66 GTO front drum brakes

Bingo! Drum was out of round. Had it turned and it seems to turn smoothly now. Had the other 3 checked also and resurfaced slightly.

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"He'd need 5 years in the fifth grade just to get an idiot certificate" Smokey Yunick re: Bill France Jr.
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