|
|
Veteran
Posts: 161
 
Location: Pearland, Texas, McPherson, Kansas | So I have been having troubles with my 57 Chrysler's brakes ever since I got the car. I've been able to get them pretty good, only needing to press the pedal about 2/3 of the way down before they catch fully, then I release and when I press them a second time it grabs right at the top of the pedal. Nice and firm. I want to get the pedal to be as firm as the second pump the first time I press it. I've replaced both rear wheel cylinders, all brake lines besides the rear two, and also the two hoses that go to the front top wheel cylinders. The front 4 wheel cylinders have been good since I bought the car. I re bled the entire system today and there is for sure no air in any lines. Do these master cylinders have residual pressure valves? Do I need to adjust the push rod some? One thing to add is that this car does have power brakes, and the bellows booster is freshly rebuilt as well.
Any help is greatly appreciated.
Jacob |
|
| |
|
Expert
Posts: 2490
Location: Kansas City, KS | If you're confident all the air is out of the system, then it sounds like you need to adjust the brake shoes. |
|
| |
|
Expert 5K+
Posts: 8947
  
Location: WHEELING,WV.>>>HOME OF WWVA | what mast. cyl. did you use-----------------------------------------------later |
|
| |
|
Expert
Posts: 3774
Location: NorCal | KcImperial - 2016-08-07 10:46 PM
If you're confident all the air is out of the system, then it sounds like you need to adjust the brake shoes.
Yep, if the brakes are loose the first pump of the pedal moves the shoes out to the drums, raising the pedal "takes another bite" and the pedal is higher. Same thing happens if the MC is too small. |
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | KcImperial - 2016-08-08 12:46 AM
If you're confident all the air is out of the system, then it sounds like you need to adjust the brake shoes.
That is what I was thinking. I dried adjusting them once before, but I probably didn't get them out far enough. Ill do that today to see how that changes everything.
Jacob |
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | 60 dart - 2016-08-08 3:10 AM
what mast. cyl. did you use-----------------------------------------------later
I'm using the direct OE replacement made by dorman, bought through rockauto.
Jacob |
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | 57chizler - 2016-08-08 1:17 PM
KcImperial - 2016-08-07 10:46 PM
If you're confident all the air is out of the system, then it sounds like you need to adjust the brake shoes.
Yep, if the brakes are loose the first pump of the pedal moves the shoes out to the drums, raising the pedal "takes another bite" and the pedal is higher. Same thing happens if the MC is too small.
That makes perfect sense, and I was actually thinking that to be the case earlier when I was working on the brakes. Now that I have some more opinions saying the same thing, I'm going to readjust. master cylinder is a brand new reproduction of OE cylinder. Made by dorman and distributed through rockauto.
Jacob |
|
| |
|
Expert 5K+
Posts: 7389
Location: northern germany | check the residual valve. |
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | 1960fury - 2016-08-08 4:19 PM
check the residual valve.
I would, but I don't know how to do that. |
|
| |
|
Expert
Posts: 1906
Location: Ontario, Canada | If, " raising the pedal "takes another bite",
I would say the residual valve is working. If not, it probably wouldn't take another bite.
Greg |
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | LD3 Greg - 2016-08-08 9:53 PM
If, " raising the pedal "takes another bite",
I would say the residual valve is working. If not, it probably wouldn't take another bite.
Greg
Its definitely taking another bite, because i can press the first pump a ways of the way down and when it finally starts grabbing, I release it. The next pump grabs right at the top and is as firm as all get out.
Jacob |
|
| |
|
Expert
Posts: 3393
Location: Chestertown, NY ( near Lake George) | Make sure you have no more than 1/4- 3/8 free pedal travel. |
|
| |
|
Expert 5K+
Posts: 8947
Location: WHEELING,WV.>>>HOME OF WWVA | did you bench bleed it real good and there shouldn't be any need for a residual valve --------------------------------------------------later |
|
| |
|
Expert
Posts: 3393
Location: Chestertown, NY ( near Lake George) | Chuck, correct, drum brake masters have them built in. |
|
| |
|
Expert 5K+
Posts: 8947
Location: WHEELING,WV.>>>HOME OF WWVA | i've had distribution blocks/prop. valve go bad while bleeding brakes . that one was terrible to figure out the problem , terrible------------------------------------------------------later |
|
| |
|
Expert 5K+
Posts: 7389
Location: northern germany | LD3 Greg - 2016-08-08 10:53 PM
If, " raising the pedal "takes another bite",
I would say the residual valve is working. If not, it probably wouldn't take another bite.
Greg
its not that its always either working or not. could be a partial/delayed working residual valve caused by dirt in the system or simply an aged leaking valve. i once had that problem and a new residual valve fixed it.
so if after pumping, following the bleeding, all is okay, then all is okay. but from what i understand the firm pedal doesn't stay firm. right? that could very well be a leaking residual valve, as a residual valve is supposed to hold a certain pressure in the system, if it slowly leaks it can lead to the said problems.
Edited by 1960fury 2016-08-10 8:37 PM
|
|
| |
|
Veteran
Posts: 161
Location: Pearland, Texas, McPherson, Kansas | 1960fury - 2016-08-10 7:30 PM
LD3 Greg - 2016-08-08 10:53 PM
If, " raising the pedal "takes another bite",
I would say the residual valve is working. If not, it probably wouldn't take another bite.
Greg
its not that its always either working or not. could be a partial/delayed working residual valve caused by dirt in the system or simply an aged leaking valve. i once had that problem and a new residual valve fixed it.
so if after pumping, following the bleeding, all is okay, then all is okay. but from what i understand the firm pedal doesn't stay firm. right? that could very well be a leaking residual valve, as a residual valve is supposed to hold a certain pressure in the system, if it slowly leaks it can lead to the said problems.
No, the pedal is pretty soft on the first press until about 2/3 of the way down. Then, on the second pump the pedal is rock solid from the top to the bottom just like it is supposed to be.
Jacob |
|
| |
|
Expert 5K+
Posts: 7389
Location: northern germany | J97_Imperial - 2016-08-15 7:56 PM
1960fury - 2016-08-10 7:30 PM
LD3 Greg - 2016-08-08 10:53 PM
If, " raising the pedal "takes another bite",
I would say the residual valve is working. If not, it probably wouldn't take another bite.
Greg
its not that its always either working or not. could be a partial/delayed working residual valve caused by dirt in the system or simply an aged leaking valve. i once had that problem and a new residual valve fixed it.
so if after pumping, following the bleeding, all is okay, then all is okay. but from what i understand the firm pedal doesn't stay firm. right? that could very well be a leaking residual valve, as a residual valve is supposed to hold a certain pressure in the system, if it slowly leaks it can lead to the said problems.
No, the pedal is pretty soft on the first press until about 2/3 of the way down. Then, on the second pump the pedal is rock solid from the top to the bottom just like it is supposed to be.
Jacob
??? isn't that what i posted? please explain what you mean by "first press". if only the first press is soft after the bleeding and all following are rock hard you ain't got a problem. am i missing something? again, if the firm pedal does not stay firm after some time of driving, it could be the residual valve.
Edited by 1960fury 2016-08-16 8:32 AM
|
|
| |
|
Board Moderator & Exner Expert 10K+
Posts: 13045
Location: Southern Sweden - Sturkö island | - Adjust the brake shoes in all 4 corners.
- Press down the brake pedal once and take a proper measurment from the pedal to the floor (or other reference), release the brake pedal
- Wait 30 seconds and press down the pedal again - it should go down approximately to the same measurement.
If you mean that you always must press twice on the brake pedal to get a proper height on the brake pedal, then there's still air in the system, or, as Sid informs, a problem with the residual valve |
|
| |
|
Expert 5K+
Posts: 6497
Location: Newark, Texas (Fort Worth) | http://www.imperialclub.com/Repair/Brakes/bleeding.htm
From Scavenger:
One sure way of telling if you are getting any action from the hydraulic system would be to remove a drum and have a partner observe at the brake cylinder while you GENTLY apply the brake pedal. I overhauled the brakes on my '57, and it took several trips around the car bleeding the brakes before I got a substantial "pedal". I would also suggest adjusting the brakes so they are just barely dragging, then bleed them Thoroughly. This whole process requires a lot of patience. It also helps if you have an assistant helping you. One person inside operating the brake pedal, another at the wheel being bled opening and closing the bleeder valve on wheel cylinder. Also, as someone else suggested, check the adjustment at brake pedal. |
|
| |
Brakes Needing 1 Extra Pump Even After Full Bleed
