Drum adjustment
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Pro
Joined: Jan 2008
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From: Huntersville NC
Drum adjustment
My friend from work always says that his uncle "adjusts" his drum brakes by going real fast backwards and slamming on the brakes. He says that after that all 4 brakes are in the perfect spot. Is that true? I hope to have my car back on the ground this weekend and rebleeding and adjusting my breaks are the last two things I need to do.
Le Mans Master
Joined: Jun 2004
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From: Southeast Missouri
My friend from work always says that his uncle "adjusts" his drum brakes by going real fast backwards and slamming on the brakes. He says that after that all 4 brakes are in the perfect spot. Is that true? I hope to have my car back on the ground this weekend and rebleeding and adjusting my breaks are the last two things I need to do.
Last edited by Ron Miller; Apr 23, 2010 at 01:47 PM.
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From: Washington Michigan
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Army
JohnZ is correct...in addition to being 'frozen' I have seen MANY self adjusting mechanisms installed incorrectly and thus not work. Unless you have personally had the drums off and eyeballed their installation and condition I wouldn't trust them too much...
Le Mans Master
Joined: Feb 2008
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From: NJ Hockey beer league
The self adjusters in my 64 work quite well. I went through my entire braking system and corrected some places where Bubba had been and have really not had to touch them for adjustment since. I wish my 59 had them. 
Pilot Dan
Pilot Dan
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Army
When you back up and press the brake a torpedo shaped adjuster 'unscrews' and expands the shoes...a 'star wheel' works against a stop that has a ratchet effect to hold the adjuster in place after it moves... When driving forward the 'stop' keeps the adjustment from loosening. The brake shoes have special slots in them to accept the adjuster and an extra spring holds the ratchet plate against the star wheel....you could probably retrofit adjusters on an older car but its just too easy to do it manually IMO.
Drifting
Joined: Jul 2007
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From: california
i worked on tons of 63-64 vettes and chevys back in the day. the star wheel self adgusters are 4 corner specific, they would self adjust if just by backing up slowly and pumping the brake. it was a no brainer because just backing up every day would adjust the drum brake shoes.
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From: Greenville, Indiana
Safety Car
Joined: Aug 2006
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From: Location, Location QC,NY
So what method do you guys prefer for non self adjusting C1 drums?
I think the book says tighten until there is some drag, and then back off one turn? I'll go look it up, I have to do mine.
Paul
I think the book says tighten until there is some drag, and then back off one turn? I'll go look it up, I have to do mine.
Paul
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From: Greenville, Indiana
Getting all four of them evenly adjusted is more important than how you do it, especially on the front wheels.
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Army
On my Dad's car lot back in the '60s/'70s where many makes of cars rolled in and lots had manual brakes he always told me to tighten them up until you can't turn the wheel with your hand then back off 8 'clicks'. I've done that for years on too many cars to count with perfect results...
Le Mans Master
Joined: Nov 2009
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From: 50 kilometers outside Oslo Norway
I changed the brake cylinders and shoes on my 64 this morning.
I was careful to check that the stop plate for the 'star wheel' really stopped the 'star wheel' for turnig the wrong way.That the stop plate was close to the star wheel.I also adjusted the star wheel a little so the shoes touched the drum a little before putting the wheels back on. I also cleaned and sanded the inside of the drums to make the real clean.
Tha car goes straight as an arrow after i did this job. So i am happy as long as it continues to work like this
I was careful to check that the stop plate for the 'star wheel' really stopped the 'star wheel' for turnig the wrong way.That the stop plate was close to the star wheel.I also adjusted the star wheel a little so the shoes touched the drum a little before putting the wheels back on. I also cleaned and sanded the inside of the drums to make the real clean.
Tha car goes straight as an arrow after i did this job. So i am happy as long as it continues to work like this
Last edited by TheSaint; Apr 24, 2010 at 05:23 PM.
Le Mans Master
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From: 50 kilometers outside Oslo Norway
This i did not think of: I always remove the star wheels, separate them and clean the threads, apply a thin film of moly lube, and re-install them
Why did i not seperate , clean and lubricate the star wheel as JohnZ did.I should have thought of that.
And i did not know that the star wheels did adjust when backing up and brake.I knew they are self adjusting but not how it works.
I tighten the star wheel so the shoes hangs on the drums just a little.Did i do a mistake by tighten the star wheels a little?
Why did i not seperate , clean and lubricate the star wheel as JohnZ did.I should have thought of that.
And i did not know that the star wheels did adjust when backing up and brake.I knew they are self adjusting but not how it works.
I tighten the star wheel so the shoes hangs on the drums just a little.Did i do a mistake by tighten the star wheels a little?
Last edited by TheSaint; Apr 24, 2010 at 05:37 PM.
Team Owner
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From: Greenville, Indiana
What you're calling the "stop plate is actually the gizmo that pushes on the star wheel to adjust the brakes when you stop in reverse. It doesn't stop the adjuster, it is what turns it.
Preliminary shoe adjustment is set with calipers to match the drum diameter then just slide the drum over the shoes. Since I (and most people I know) do not own the calipers, I just rotate the adjustment tight enough to slide the drum over the shoes, step on the brake pedal, and adjust again if required. The self adjusters will take care of the rest of it.
Anytime you remove the drums, you should check for free operation of the self-adjuster mechanism.
Le Mans Master
Joined: Nov 2009
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From: 50 kilometers outside Oslo Norway
Sounds that ithe adjustment i did was okay then
But i cant see ho that gizmo tuns and adjust the shoes. But i really dont know much about drum brakes.
I might have to take the wheels off and lubricate the self-adjuster mechanism just to be sure.
But i cant see ho that gizmo tuns and adjust the shoes. But i really dont know much about drum brakes.
I might have to take the wheels off and lubricate the self-adjuster mechanism just to be sure.
Pro
Joined: Oct 2005
Posts: 524
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From: St. Charles Mo.
What you're calling the "stop plate is actually the gizmo that pushes on the star wheel to adjust the brakes when you stop in reverse. It doesn't stop the adjuster, it is what turns it.
Preliminary shoe adjustment is set with calipers to match the drum diameter then just slide the drum over the shoes. Since I (and most people I know) do not own the calipers, I just rotate the adjustment tight enough to slide the drum over the shoes, step on the brake pedal, and adjust again if required. The self adjusters will take care of the rest of it.
Anytime you remove the drums, you should check for free operation of the self-adjuster mechanism.
Preliminary shoe adjustment is set with calipers to match the drum diameter then just slide the drum over the shoes. Since I (and most people I know) do not own the calipers, I just rotate the adjustment tight enough to slide the drum over the shoes, step on the brake pedal, and adjust again if required. The self adjusters will take care of the rest of it.
Anytime you remove the drums, you should check for free operation of the self-adjuster mechanism.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana