brake help

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2 Darts said:
Worried about panic stops, eh? Recall that maximum braking effort is achieved immediately prior to lock up. A locked up wheel can not be steered. The factory bias in the system is towards the front. Lock up the fronts and the car tends to go the direction in which it was heading prior to lock up. Lock up the rears and the back end wants to come around.

If you're still not impressed with the performance of your drum brakes they may be out of adjustment or the linings may be glazed.

The drum brakes are equipped with self-adjusting mechanisms (little tab that contacts star wheel adjuster). To engage them, drive backwards and apply brakes HARD. It is not necessary to be going very fast, 5-10 mph is adequate. You may hear a pop or clang during this operation.
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If the adjusters are working. Sometimes the best way is to block the rear on jack stands, put the car in neutral and reach through the slot on the backing plate with a screw driver and adjust until the tire barely turns then back it off a little. You'll know you're doing it right when you hear a series of clicks as you move the adjuster wheel against the adjuster, and spin the tire at the same time to feel for resistance. Once you get it close you can keep 'em maintained in the above manner.
 
i have no idea what or where the adjuster valve is, I will do a little research and try it.
 
hamsterhats said:
i have no idea what or where the adjuster valve is, I will do a little research and try it.
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Are the brakes working as well as they did before the flexible hose broke?

If not, then you still have air in the system. Replacing a broken flexible hose would not cause the power booster to go bad or cause the rear brakes to go out of adjustment.

BTW: the adjuster that ramenth mentioned is not a valve, but a double ended threaded piece inside the drum that the bottom of the shoes pivot on.

The valve that someone mentioned is the proportioning valve, which you can find by following the metal brake lines from the MC down to the inside of the front sub-frame.
 
hamsterhats said:
i have no idea what or where the adjuster valve is, I will do a little research and try it.
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The best help you can get, if you're new to this, besides the great tech on this site, is to buy a manual, be it Haynes, Chiltons, or the Factory Service Manual on CD for the computer. (Sold online anyone have the website handy?) They all have some pretty good exploded views of a drum brake system for you to familiarize yourself with, including part names, etc.

Sorry, man, I've been wrenching for over 20 years now, doing everything from frame straightening to computerized driveability and I consider brakes all basic gravy work, easily diagnosed, easily fixed, that I forget that sometimes others are just learning.

Take the drum off and you'll see the basic components of your system: the shoes, the adjuster, the hold downs, springs, etc. The adjuster is the part that goes between the two shoes with what looks like a little gear on it. That little gear, or star wheel, should turn freely, by turning it with a screw driver using the axle as leverage or reaching in with a pair of side cutting pliers and gripping it. (You'll have to pry out the adjuster arm, the little piece of metal that rides against it.) Experiment a little bit and you'll see that it if you turn it the right way the shoes will move out a little bit and turning it the other way they'll come back together. Behind this little wheel is a slot in the backing plate, filled by a rubber plug. Pry the plug out and reach through with a screw driver and turn that little gear through the backing plate you'll see the same thing happening: the shoes will spread apart or come together. Put your drum back on and start tightening the shoes by turning the adjuster with the screw driver through the whole in the backing plate and feel for resistance as you're spinning the drum. When it's hard to turn, stop tightening and replace the little rubber plug. Done.
 
alright, cool, thanks for breaking it down! I looked for a book, found the haynes but it says that it is a book for six cylinders only, no v8. I think it was for a valient too? I will keep looking around. Also just wanted to say thanks to everyone who has helped me, i'd be lost without all the help. Thanks

Jeremy
 
hamsterhats said:
alright, cool, thanks for breaking it down! I looked for a book, found the haynes but it says that it is a book for six cylinders only, no v8. I think it was for a valient too? I will keep looking around. Also just wanted to say thanks to everyone who has helped me, i'd be lost without all the help. Thanks

Jeremy
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Just came across my old Chiltons. One covers the years 1953-1964 and the other goes 1965-1974. These books both have very good sections devoted to manufacturer specific brakes, but I'm having a b**** of a time finding a good part number to use to order one.

I just went back on the posts, but didn't see year and model of your car? Let me know and I might be able to hook you up with diagrams and break down, specific.

Did you find your proportional valve? This will be in line of the hydraulic sytem. Trace the lines coming out of the master cylinder until you come to a "block" that will have the brake lines from the master cylinder going into it and the brake lines actually going to the wheels coming out of it. As was suggested this valve system may be stuck. Contaminated fluid, particulate matter from worn cups in the master, bad o-rings, etc, may be causing this to stick. My '82 Dip has all brand new brakes, lines, master, rotors, drums, calipers, wheel cylinders, crap for pedal! Bad prop valve keeping me from stopping 400 horsepower isn't fun.

Don't attempt a rebuild on this unless you have a lot of experience with brakes and overhauling things like wheel cylinders and calipers. It's easy to screw up and could put you in an even worse position than you are.

As for the help that's what we're all here for. I personally don't know everything (it's been pointed out to me subtly...)but if I'm wrong hopefully someone with some better suggestions will chime in and lead us both down the primrose path.
 
ok, changed the front pads, the wear is one sided only. The outer pads are worn twice as much as the inner. I am assuming that the piston is in need of some work. Found my idle and braking problem, bad booster, when plugged the motor runs smooth as silk. Anyways, is it hard to rebuild the piston and assembly? Any input appreciated!
 
If you don't rebuild your booster, I have a almost new (20 miles) 73 Duster disc brake car booster 4 sale @ $85.00 plus shipping..pm if interested or [email protected]
 
if you have single piston sliding calipers. it sounds like the caliper isnt sliding from what your describing. take the caliper off and clean the area where it slides on then put some caliper lube on it. throw on some new pads and check after some miles are on the pads to see if they are wearing evenly.
 
hamsterhats said:
ok, changed the front pads, the wear is one sided only. The outer pads are worn twice as much as the inner. I am assuming that the piston is in need of some work. Found my idle and braking problem, bad booster, when plugged the motor runs smooth as silk. Anyways, is it hard to rebuild the piston and assembly? Any input appreciated!
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rebuilding a caliper is easy. Unfortunately the rebuild kits can cost almost as much as a new caliper.

The problem could also be a partially plugged flex line, where pressure on the pedal is enough to engage the brakes but the plugged lined prevents the fluid from returning an relieving pressure on the caliper.
 
autozone has calipers for a 73 duster for 30 bucks a piece, should i get them?
 
hamsterhats said:
autozone has calipers for a 73 duster for 30 bucks a piece, should i get them?
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For $30 a piece, I'd buy them. You'd be way ahead by the time you buy the rebuild kits, disassemble the calipers, clean the bores and pistons, put in new seals, etc.... heck you could be back on the road and cruising by then. Of course, you'll have to bleed the brakes again, but you're getting to be an old pro at that. Did you turn the rotors when you put the pads on the front??? You'd be surprised at how smooth the brakes operate with a fresh turn of the rotors. It sounds like with a little love, those fronts should be road ready. I'm with the other guys on the back brakes, but I would dis-assemble them, take the star wheel adjusters out and take them apart, clean the threads and use some anti-seize compound on the entire assembly. My oldest trick when I'm doing brakes is to jack up the rear, take both drums off, but only do one side at a time, that way you always have a reference right there should you have any questions during re-assembly. One other thing I would suggest is to have the rear drums turned while you're back there. Over time, the shoes will wear the drum where they contact it, causing a ridge at the outside where the shoes don't wear it. When you are adjusting the rears, you can get the shoes to just rub the drums, which is where you want them, but if you need to take the drum off and there is a ridge, you have to back the shoes way off to get the drum off. By turning the drum, the ridge is removed and the next time you need the drums off, you will only have to back the star wheel off a small amount. A well adjusted and well maintained system will provide sound peace of mind to your cruising. One other thing, that critter in your avatar is worrying me!!! I wouldn't gewt that close if I were you, he looks like he means business!!! Good luck with your ride, Geof
 
sewer and cocsig have it right on the money. If you buy the calipers at AZ also buy the little packets of brake silicone they usually have for sale at the front counter. Clean all your hardware and use this like a grease on the adjuster threads and every where the pads and calipers make contact with the front brake anchors (or brackets). It's designed to take the heat from braking, it will keep everything clean and moving. Also spending about $10 each to turn your rotors and drums with a local machinist or brake shop will go a long way to enjoying your ride.
 
tahnks guys! I will order everything today! Wasn't sure which size shoes to order, guess i just measure the drum right? Thanks again! Can't wait to finally drive it!
 
Alright, ordered front calipers, booster and cylinder and pads all the way around. Need some help with the rear drums. When i measured the drums they were 10", i go to order them under 71 dodge dart, no luck. Do you think these drum are from a 73 duster like the front discs? Help please!
 
i found them for a 73 duster with 10" drums. Are they the same on both sides? will these work?
 
If by both sides, you mean passenger side and driver side then yes both are the same. If the rear brakes are from a 73 then they should have the large bolt pattern lugs.

If you're not sure take the old ones in and match them to the new ones you are buying.
 
Step away from the critter there hampsterhats, he's reelin' back for an attack!!! Oh, about the shoes. The rear shoes are the same from side to side, but there are 2 different shoes. Make sure that each side gets one of each. Now here's the tricky part, when you put the 2 different shoes side by side, you will notice that the braking material is mounted to the shoe differently for the front shoe than the back. When the wheel is spinning forward, which it is most of the time, the binding (braking material) on the front shoe should not be right at the top of the shoe. The front shoe should have the binding close to the bottom of the shoe, and the rear shoe should have the binding close to the top. What this does is allow the shoe to start to work slowly as the drum rotates around in forward motion. If the binding were near the top of the front shoe, it would cause the shoe to "grab" the drum and cause lock-up. By shifting the binding on the shoe, the brakes have what is called a "trailing edge" action. Remember that the wheel cylinder pushes the shoe out from the top, and if the binding were near the top of the front pad, it would contact first, and hard enough to lock up your brakes. If your old shoes are still on, (they are aren't they??), this should be the case with them as well. Remember to take one side apart at a time to allow a visual reference at hand in case you get stuck. FYI, you can measure the width of the binding on your new shoes, and the wear pattern on your drums to make sure that you have the correct width shoe. Good luck, and happy braking, Geof
 
hamsterhats said:
Alright, ordered front calipers, booster and cylinder and pads all the way around. Need some help with the rear drums. When i measured the drums they were 10", i go to order them under 71 dodge dart, no luck. Do you think these drum are from a 73 duster like the front discs? Help please!
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Did you measure the inside of the drum, or the outside? The diameter used for sizing the shoes is the inside diameter.
 
72, i measured the inside. cosgig, awesome info! Everything should be here tomorrow! Spending the whole day with her!
 
if you put a piece of vacumn hose tightly on the bleeder and submerge the end in a jar of brake fluid you can crack the bleeder and pump the brake till you see no more bubbles in the jar because when you release the brakes they cant suck air with the hose submerged. thus you can pump the crap out of them till theres no more air. just dont let the reservoir go dry and close the bleeder screw before disconnecting the submerged hose.
 
thats how i did it daredevil, worked great! Now i have to do it again after installing the new components. My young neighbor loves to come over and help!
 
hamsterhats said:
72, i measured the inside. cosgig, awesome info! Everything should be here tomorrow! Spending the whole day with her!
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Also a good idea to take digital photo of each side before starting & print out for reference.
Good Luck
 
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