Imperial Homepage -> Repair -> Brakes ->Adjustment
Question from Philippe (1957):
I have an excessive travel of the pedal before brake apply. The brakes are efficient only in the last 1/3 of the travel (but the pedal don't touch the floor) with or w/o the brake booster and the distance between no brake and wheel locked is closed. I have adjust the master cylinder rod according to the FSM but I don't feel in security with all this "gap". Do you think I must lengthen the rod by adjusting the nut rod ? Or is it a problem of bleeding? I use silicone fluid.
Reply from Dick:
There should be just a little free travel of the pedal before it contacts and begins to move the piston in the master cylinder. No more than 1/2 cm, at most, as measured AT THE PEDAL, not at the rod itself. But there must be some free travel, so that the pressure relief port in the master cylinder is opened up after each use. If your pedal is too low, but otherwise everything is OK, it sounds to me that you just need to do a normal brake adjustment at the wheels. Your car doesn't have self adjusters. Just go through the normal adjustment at each wheel (tighten each wheel until it cannot be moved by hand, then back off 8 clicks), and see if that helps.
Question from Jeff (1958):
My brother and I just finished a total brake job on his 58 4dr and we are having a little trouble adjusting them properly. We have the manual and we have tried to follow the instructions but they seem to be too tight. Does anyone wiser then us have a sure fire method for adjusting them? The manual says to adjust them until they are so tight that the wheel locks then back the adjusters off till they spin freely. We did this but the brakes still seem too tight. Should we do the front or rear adjusters first? Thanks for any tips or hints you can offer.
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From Joe:
I believe you have been bitten by the same problem I had. On the older Imperials and other Chrysler Corp. cars with the "Total Contact Brake System" the relined shoes are supposed to be ground down on a special machine which matches the internal diameter of the drum to that of the relined brake shoes. If the shoes are installed as is from a rebuilder, they are too large to allow proper operation, especially after some heat buildup in normal use.
You may be able to find someone in your area who still has one of the machines for doing this. I had a local dealer try to install relined shoes several years ago. He did not have the correct equipment to grind down the shoes. As a consequence, when I drove the car home, I smoked the brake linings. The car has hardly been driven since, and I am afraid I have warped the drums front and rear. You may have luck if you look for a clutch and brake service company which can work on farm tractor brakes. I understand that they are some of the only people left which may have the equipment.
The reason that the brake shoe grinding equipment is so rare now is that the EPA and OSHA made most of the dealers throw away the equipment because of asbestos dust particles being released when the grinding was under way. The danger is minimal if done correctly with the original dust shields in place. Another instance of government bureaucrats gone wild. I don't know if I can stand much more government protection!
From Jim:
The new brakes need those HARD FAST stops. Drums and new linings are rough and need to have this 'fuzz' worn off. This is called 'burnishing the brakes' I have made this a practice with every new brake job. I learned this in my first days of car ownership and maintenance.
It is the way to get the new brakes smoothed up and working up to their capability. The smoother the surfaces of drum and lining the more area that is touching, so it makes for better brakes.
From Nancy:
If your brakes are over tight it may be that the shoes were relined with lining that is too thick. Chic got hold of some of these once too. He got them at a local auto parts and they had them ground to fit for him. Currently none of the brake linings we have been buying contain any asbestos. It has apparently been banned and recent relines don't have it. My guess is if these shoes were relined recently they would not have any asbestos. If they were NOS or NORS then that would be another story.
Did you put new springs and all new retaining hardware on the brakes? Are the wheel cylinders relatively new? Center plane brakes really love to stick. Weak brake springs may make your brakes shoes not return fully which might makes the brakes smoke and smell. By the way new brake lining generally smells for the first half dozen or so times you drive the car anyway even on late models. I wouldn't worry unless the brakes started to smoke as they really can catch fire if things get hot enough. Had it happen once on a '57 Imperial on an Interstate. Luckily didn't hurt the car much.
Question from Rex (1959):
How does one properly adjust those front brakes?
Reply from John:
The adjust you will see 2 adjusting cams on each front wheel. You will need a 7/16 socket & to tighten, you turn them in the direction of the FORWARD rotation of that wheel. The amount of travel on the adjuster is very little, less then a complete turn.
Question from Timothy (1960):
I've been busy over the last three weeks puttering away on a brake job on the sixty in my "spare" time (I have none hence 3 weeks for a 1.5 day job...). Here's the situation...No pedal! no matter how many time you pump it. We have replaced the front shoes and hoses, rebuild the front wheel cylinders, took apart the back drums and realized that the have already been done in the not to distant past and left it at that for the moment and adjusted everything, then gave it a try. When that didn't work we checked for leaks and air and decided that the master cylinder was leaking out the back. Yanked it and rebuilt it, reinstalled, rebled, readjusted, and still nothing. The car slows down and will sort of stop if it's not on high idle or pointed downhill. I have a new rear hose which I am still meaning to install but both BJ and I can't see how a hose that's not leaking could cause the problem.
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From Paul:
After all that you have done, try going back and readjusting all the brake shoes. If you turned the adjusting cam in the wrong direction on just one shoe, then your brake pedal will go to the floor as you have indicated. Use a 7/16 inch six sided socket, of 3/8 drive to adjust the shoe cams. Six of the eight tighten in the forward direction of the wheels. The rearmost two, which are most frequently adjusted wrong, are tightened by turning in the reverse direction of the wheels. After you have properly adjusted the cams, that may solve the problem. But if it doesn't, then be sure to bleed the brakes in the proper order: right rear, left rear, right front lower, right front upper, left front lower, left front upper. Right and left are as you sit in the driver's seat of the car.
From Mikey:
On my '62 it clearly says NOT to adjust the length of the pushrod between the booster and master cylinder. I only know because I switched boosters once, and was about to do just that when I read the notice. I agree that if its too long the cylinder won't be able to fully return , and if its too short there will be wasted motion before the cylinder starts to apply the brakes. I'd go back and double check the adjustment and maybe even double check the bleeding, that's a long distance to push an air bubble around. As far as the advice about the check valve in the master cylinder, that's also a very good thing to check and very easy too.
Question from Tony (1960):
How do you adjust the brakes on a 60?
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From John:
The adjuster have 2 lugs per wheel that stick out through the back of the dust shield. You may also be able to adjust with a 7/16 offset box wrench, its just easier with a socket since you can just reach around instead of crawling underneath. Wearing safety glasses is a good idea just in case. The spring doesn't usually unhook from the opposite end but if it doesn't engage the hook, it does snap back with a lot of force. The removal part is no problem since you are just prying against the shoe & lifting the spring, at this point, the spring is not under much tension & will pop right off. When installing however, you are stretching the spring & caution should be used.
From Brett:
Basically the rear wheel adjusters turn CCW on the left and CW on the right as you look at the back of the wheel. The front brake adjusters BOTH turn the SAME direction as the wheel when the car moves forward. Spin the tire, tighten the adjuster until it stops the wheel, then untighten about a quarter turn.
Clarification from John:
One clarification on this. The adjusters all tighten in the same direction as the wheel is turning in the forward direction with the exception of the rear shoe on each rear wheel. These turn in the reverse direction. To sum up, first 3 on drivers side CCW, last one CW. Passenger side, first 3 CW last one CCW.
From Jack:
Before you adjust the brakes try stepping on the brake pedal a few times to center the brake shoes. Sounds also like you still have air in the system. I had a rough time getting my brake pedal up after the last brake job. It was a total brake job, lines, wheel cylinders, master, and hoses. I bench bled the master before I installed it. I went through the whole cycle of bleeding all wheel cylinders to no avail . Finally in disgust I re-bled the master at the line going in and to my surprise I got a hiss of air. The pedal came right up to the top.
From Joe:
I use a 7/16 swivel socket that has an open end wrench at the other end. What I did not read as part of the brake adjustment was to rotate the wheel in question the direction of travel, so must be off the ground, and adjust it as said prior, but remember that new lining as it seats will need another adjustment very soon, as when I do one, it needs another adjust in about 3 to 4 weeks, but I drive my 61 LeBaron about 20 to 30 thousand miles a year. I have several sets of spare brakes for it because I drive them so much. When I adjust them, I rotate the wheel in a forward motion on a jack stand and tighten till the wheel stops, then loosen about 1/32 of a turn, ever so slight, as I do not want to constantly be doing them.
Question from Gavin (1961):
How do you adjust the front brakes on a 61 Imperial. Mine are pulling to hard to the right. The shop manual does not go into detail about adjustment at all.
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From Brett:
The biggest problem I've had with Imperial brakes is getting them adjusted properly. The front brakes adjust differently than the rear and most repair techs assume a Chrysler product will work the same as a GM or Ford. We all know that's a dangerous assumption on many levels! By 1963 Chrysler no longer used the dual-front brake cylinders, so the adjustment issues may no longer be an issue for you.
From Ed:
Put the car on jack that lifts both front wheels. Adjust the brake from the underside of the car: Loosen the retainer that keeps the adjustment screw from being adjusted. Tighten the adjustment screw until it stops the wheel from turning. Then loosen it slowly until the wheel turns freely, (just barely looser than a slight scrapping sound, which would be the brake shoe against the brake drum). Do that to both front wheels and try to be exact on the amount that you loosen each one so that they are equally loosened from the referenced "scrapping sound." Tighten the retainer to the adjustment screw, to keep the brakes at that setting. If it still grabs on one side, you probably have a damaged drum on the right side that must be removed and "turned" on a machine to be exactly round again.
From Frank:
There are two adjusting cams for each drum. One cam is for the forward shoe and one is for the rear. The cams have a 7/16 adjusting head. First loosen both cams and adjust one shoe at a time. To adjust the cam, tighten it down in the direction of forward rotation. I like to give the free wheel a spin then lock it up with the cam and wrench. Slowly loosen the cam in the opposite direction until there is no drag. The idea is to get it as close as possible without drag. When you are satisfied with the adjustment do the same for the other brake shoe. You may hear a slight scrapping due to imperfections in the drum. Adjust both wheels as close as possible to avoid front end pull.
From John:
There is no retainer nut to loosen on a 61, just the adjuster itself. This is adjusted with a 7/16 wrench. To tighten, turn the adjusters in the direction of the forward rotation of the wheels. The only exception to this is on the rear wheels, the rearmost shoes tighten opposite the forward rotation. Other possible cause of grabbing could be air in the lines.
