Adjusting Rear Drum Brakes
#12
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I have mixed emotions on this "mod". Yeah, you made it quicker/easier to adjust the brakes. And that is a good thing because those self adjusters are basically worthless. But that'* just my opinion. On the other hand, I actually prefer pulling the drums everytime I adjust the rear brakes only becuase I use Brake Clean to remove the crap out (please don't use your mouth to blow the brake dust out) AND actually see the condition of the shoes and wheel cylinders.
#13
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…id be worried about the balance of the drum that is now thrown off because of the hole....
Relatively little mass was removed. Less than a penny’* worth. It’* also very close to the center of rotation, so the effect should be negligible. You’ll experience more balance problems from a little mud, snow, or road tar on the inside of your rim. Or a nail in your tire (of course, then you’ll have other problems!).
…I was wondering about the same thing, as well as the integrity of the drum itself. Are the holes for the studs drilled or cast, and will the shorter distance now between the stud holes and the adjustment hole weaken the drum?...
That, of course, is a consideration. Since that area of the drum is sandwiched between the rim and the axle flange, there shouldn’t be any flex around there. A properly installed drum and wheel assembly should not experience any linear or lateral movement in that region, therefore stresses around that area should be minimal. I will continue to monitor it for cracks and other signs of failure, however. I believe the stud holes are punched.
…I wonder if that will still pass state inspection?...
No worries. There’* a list of things they check for and looking for holes some idiot put in his brake drum is not one of them.
…The idea seems a little weak to me. For the effort you went through to drill a hole, you could have just adjusted the brakes. And even aside from that, they are self adjusting if they are in proper working condition so why even bother with the hole drilling or adjusting? If they don't adjust on there own, then there is something else wrong anyway...
Not necessarily true. As the brake drum wears, and as corrosion builds up, a ridge grows around the outside edge of the drum. You can only adjust the brakes enough to clear that ridge in order to install the drum. A properly adjusted brake should have a very slight amount of drag, this can’t be done if there’* a bit of a ridge on the drum. Self adjusting brakes work fine in theory, but they are a gross adjustment when they work and even then about all they do is keep your brakes from being terribly out of adjustment. It took me 5 minutes to throw the drum on the drill press and drill the holes. Less time than it took to pull the drum, adjust the brakes, install the drum (or attempt to install the drum), adjust the brakes, repeat. And the brakes are now adjusted where I like them. It will be a trivial task to properly adjust them at the next tire rotation, as 93 SLE suggested.
…Whoa! This is weird. You could have adjusted the brakes from behind the back plate. Leave the drum on and adjust until it the drum stops turning. Not too tight, but enough to stop the drum…
I could find no access through the backing plate and no easy way to create an access. The adjuster is up near the slave cylinder, not at the bottom of the assembly as is typical. Not exactly easy to get to the adjuster area from the back side.
…I actually prefer pulling the drums everytime I adjust the rear brakes only becuase I use Brake Clean to remove the crap out (please don't use your mouth to blow the brake dust out) AND actually see the condition of the shoes and wheel cylinders…
That is a good point. Drums are pulled yearly here as part of safety inspection and I like to look at them when the inspector pulls them off. I wouldn’t pull them off for a brake adjustment "tune up". Note that the adjuster can be loosened through the hole in order to get the brake drum off if the above mentioned ridge is present.
The brakes feel really good and there’* no noticeable vibration in the wheels. I’ll be watching them like a hawk for signs of stress for the next few months, but I don’t think there will be an issue. Thanks for all your comments, every one of them is valid and I appreciate your candor. I’m still happy.
Relatively little mass was removed. Less than a penny’* worth. It’* also very close to the center of rotation, so the effect should be negligible. You’ll experience more balance problems from a little mud, snow, or road tar on the inside of your rim. Or a nail in your tire (of course, then you’ll have other problems!).
…I was wondering about the same thing, as well as the integrity of the drum itself. Are the holes for the studs drilled or cast, and will the shorter distance now between the stud holes and the adjustment hole weaken the drum?...
That, of course, is a consideration. Since that area of the drum is sandwiched between the rim and the axle flange, there shouldn’t be any flex around there. A properly installed drum and wheel assembly should not experience any linear or lateral movement in that region, therefore stresses around that area should be minimal. I will continue to monitor it for cracks and other signs of failure, however. I believe the stud holes are punched.
…I wonder if that will still pass state inspection?...
No worries. There’* a list of things they check for and looking for holes some idiot put in his brake drum is not one of them.
…The idea seems a little weak to me. For the effort you went through to drill a hole, you could have just adjusted the brakes. And even aside from that, they are self adjusting if they are in proper working condition so why even bother with the hole drilling or adjusting? If they don't adjust on there own, then there is something else wrong anyway...
Not necessarily true. As the brake drum wears, and as corrosion builds up, a ridge grows around the outside edge of the drum. You can only adjust the brakes enough to clear that ridge in order to install the drum. A properly adjusted brake should have a very slight amount of drag, this can’t be done if there’* a bit of a ridge on the drum. Self adjusting brakes work fine in theory, but they are a gross adjustment when they work and even then about all they do is keep your brakes from being terribly out of adjustment. It took me 5 minutes to throw the drum on the drill press and drill the holes. Less time than it took to pull the drum, adjust the brakes, install the drum (or attempt to install the drum), adjust the brakes, repeat. And the brakes are now adjusted where I like them. It will be a trivial task to properly adjust them at the next tire rotation, as 93 SLE suggested.
…Whoa! This is weird. You could have adjusted the brakes from behind the back plate. Leave the drum on and adjust until it the drum stops turning. Not too tight, but enough to stop the drum…
I could find no access through the backing plate and no easy way to create an access. The adjuster is up near the slave cylinder, not at the bottom of the assembly as is typical. Not exactly easy to get to the adjuster area from the back side.
…I actually prefer pulling the drums everytime I adjust the rear brakes only becuase I use Brake Clean to remove the crap out (please don't use your mouth to blow the brake dust out) AND actually see the condition of the shoes and wheel cylinders…
That is a good point. Drums are pulled yearly here as part of safety inspection and I like to look at them when the inspector pulls them off. I wouldn’t pull them off for a brake adjustment "tune up". Note that the adjuster can be loosened through the hole in order to get the brake drum off if the above mentioned ridge is present.
The brakes feel really good and there’* no noticeable vibration in the wheels. I’ll be watching them like a hawk for signs of stress for the next few months, but I don’t think there will be an issue. Thanks for all your comments, every one of them is valid and I appreciate your candor. I’m still happy.
#15
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I always pull the drums to check out my rear brakes for several reasons;
#1, I can check the brake cylinders for leaks, I've often found cylinders that are starting to weep and have been able to avoid ruining good brake shoes before they are worn out.
#2, I can vacuum (never blow!) brake dust from the mechanism.
#3, If the self adjusters are working (and they normally do if lubed properly and assembled correctly) I may have a struggle getting them off if the drums are worn to leaving a lip on the drum, if that is the case and the shoes aren't worn out I know to budget for for new drums next reline. They wear out just like discs, just take longer to do so.
The rear brakes on my car do a lot more work than most as often the car is fully laden with a caravan behind it, the proportioning valve allows the rears to do more work.
#1, I can check the brake cylinders for leaks, I've often found cylinders that are starting to weep and have been able to avoid ruining good brake shoes before they are worn out.
#2, I can vacuum (never blow!) brake dust from the mechanism.
#3, If the self adjusters are working (and they normally do if lubed properly and assembled correctly) I may have a struggle getting them off if the drums are worn to leaving a lip on the drum, if that is the case and the shoes aren't worn out I know to budget for for new drums next reline. They wear out just like discs, just take longer to do so.
The rear brakes on my car do a lot more work than most as often the car is fully laden with a caravan behind it, the proportioning valve allows the rears to do more work.
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Will Buick rear DISK brake assy bolt up to my '92 Olds 98 Regency?????
I too object to no hole in backing plate to adj the rear (drum brakes) shoes on my Olds. Self adj feature usually inop. Backing off adjuster allows drum removal w/o headache.
Speaking of rinky-dink: Read the Olds factory manual, it sez one shoe fcns when moving fwd, and one shoe fcns when reversing.
I too object to no hole in backing plate to adj the rear (drum brakes) shoes on my Olds. Self adj feature usually inop. Backing off adjuster allows drum removal w/o headache.
Speaking of rinky-dink: Read the Olds factory manual, it sez one shoe fcns when moving fwd, and one shoe fcns when reversing.
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