New to working on brakes - need troubleshooting advice

[UFO68]

I've got a '68 Plymouth Satellite 2dr.

I replaced front shoes and springs, and I should probably get around to doing the wheel cylinders. Those have not been done yet. I also have not bled the system. Still trying to figure that one out. Never bled a brake system before.

When the car is off, pedal is hard.

When car is running, pedal is soft, all the way to the floor. With basically no stopping power, the brake light on the cluster comes on before I can get stopped. I'm pretty sure I have power brakes, well at least, I'm supposed to.

Where do I start with working through this?

Thanks!!

 

[dadsbee]

Well if you didn't have any brake lines off, or knock a wheel cylinder piston out when doing the shoes, you shouldn't need to bleed anything.... I would suggest you didn't adjust the new shoes out to just shy of the drums.

 

[slepr1]

 

[MoparLeo]

Wow. First get/download a Factory Service Manual and read the brake section.
Never drive a car on public streets to "test" your brakes. You can "feel" the brake pedal in your driveway.
The brakes are the most critical system on any vehicle and demand the most attention.
The car is over 50 years old. Replace all hydraulics, brake lines. Flush entire system first so you don't just pump the goo in the lines into your new wheel cylinders. Clean/or replace the wheel bearings and seals. Pack bearings with new grease. Rear axle bearings also need repacking occasionally ( 50 years is nice)Check drums to make sure they are still within oversize specs. Replace in pairs when needed. It always helps to have someone with experience in doing brakes to help you. An extra set of eyes and hands is always good.
https://moparconnectionmagazine.com/gallery-your-ultimate-classic-mopar-brake-restoration-guide/

 

[PurpleBeeper]

You have power drum brakes front & rear (fyi).
1. Bleed (the air out of) your brake lines. One each brake, there's a little bleeder screw on each wheel cylinder (a little hole in the center of it). Spray those down BIG TIME with PB Blaster rust penetrant. Soak & repeat. Soak again and wait 1-day. Use SIX POINT sockets or box end wrench and "crack open" those bleeder screws about 1/2 turn. Do them one at a time 1.passenger rear 2. driver rear 3. passenger front 4. driver front. One brake at a time, have a buddy push down slowly on the brake pedal while you "crack open" a bleeder screw. As he pushes the pedal closer to the floor, you close off that bleeder screw. He lets the brake pedal move back up & repeat. You're basically trying to "burp air bubbles" out of the brake lines. Each time, make SURE you close off the bleeder screw before your buddy releases the brake pedal or you'll suck air back into the brake line....just "burp" it out again if this happens. All the while, keep topping off the brake fluid in the master cylinder reservoir (slide that metal wire clamp thing to one side by prying with a screw driver and it will open up).

2. After you've bled each of the brake lines, in order, and until you got a good flow of brake fluid out (& no air bubbles) whenever your buddy pushed down on the brake pedal.....then test the brakes with the engine running.

3. If the brake pedal still goes to the floor, then look for leaking brake fluid anywhere along the brake lines going to any of the brakes. You can also inspect the wheel cylinders (or near them) for signs of leaking brake fluid. If you find a leak, fix it and bleed the brakes again.

4. If no leak is found, the brakes have all been bled and there aren't any leaks.....then for sure, your master clylinder is bad.

Let us know. We can all talk you through replacing a master cylinder if needed.

 

[MoparLeo]

Read the Service Manual first. That book is your bible,

 

[Mr. Mike]

Factory service manual reprints can be had for $50 or so, check ebay for used. One thing Mopar never did was change much from year to year except body styling, so if you find a cheap 1965 to 1972 FSM buy it.
Depending on the age of everything attempting to open bleeder valves results in snapped off screws.
Also be extremely careful older brakes shoes contain asbestos.
check youtube videos like

 

[WileE]

Wow. First get/download a Factory Service Manual and read the brake section.
Never drive a car on public streets to "test" your brakes. You can "feel" the brake pedal in your driveway.
The brakes are the most critical system on any vehicle and demand the most attention.
The car is over 50 years old. Replace all hydraulics, brake lines. Flush entire system first so you don't just pump the goo in the lines into your new wheel cylinders. Clean/or replace the wheel bearings and seals. Pack bearings with new grease. Rear axle bearings also need repacking occasionally ( 50 years is nice)Check drums to make sure they are still within oversize specs. Replace in pairs when needed. It always helps to have someone with experience in doing brakes to help you. An extra set of eyes and hands is always good.
https://moparconnectionmagazine.com/gallery-your-ultimate-classic-mopar-brake-restoration-guide/

^^ I could not agree more. New hydraulics !!!!!!!

 

[MoparLeo]

Free FSM downloads here:
https://mymopar.com/service-manuals/
Get the replacement parts before you start to take things apart. When they break or strip you will have the parts already on hand. But if you just replace them ( not really expensive) you don't have to worry about it.

 

[UFO68]

You have power drum brakes front & rear (fyi).
1. Bleed (the air out of) your brake lines. One each brake, there's a little bleeder screw on each wheel cylinder (a little hole in the center of it). Spray those down BIG TIME with PB Blaster rust penetrant. Soak & repeat. Soak again and wait 1-day. Use SIX POINT sockets or box end wrench and "crack open" those bleeder screws about 1/2 turn. Do them one at a time 1.passenger rear 2. driver rear 3. passenger front 4. driver front. One brake at a time, have a buddy push down slowly on the brake pedal while you "crack open" a bleeder screw. As he pushes the pedal closer to the floor, you close off that bleeder screw. He lets the brake pedal move back up & repeat. You're basically trying to "burp air bubbles" out of the brake lines. Each time, make SURE you close off the bleeder screw before your buddy releases the brake pedal or you'll suck air back into the brake line....just "burp" it out again if this happens. All the while, keep topping off the brake fluid in the master cylinder reservoir (slide that metal wire clamp thing to one side by prying with a screw driver and it will open up).

2. After you've bled each of the brake lines, in order, and until you got a good flow of brake fluid out (& no air bubbles) whenever your buddy pushed down on the brake pedal.....then test the brakes with the engine running.

3. If the brake pedal still goes to the floor, then look for leaking brake fluid anywhere along the brake lines going to any of the brakes. You can also inspect the wheel cylinders (or near them) for signs of leaking brake fluid. If you find a leak, fix it and bleed the brakes again.

4. If no leak is found, the brakes have all been bled and there aren't any leaks.....then for sure, your master clylinder is bad.

Let us know. We can all talk you through replacing a master cylinder if needed.

Hey PurpleBeeper,
So, I followed your instructions and the only wheel that had brake fluid flow out was the passenger front wheel. The other 3 had no fluid that came out. I'm thinking probably collapsed rubber lines or blockage in the metal lines? At this point, I'm thinking I should replace the wheel cylinders, rubber tubes, fittings, etc., and then bleed again?

I did attempt to bleed with the lid of master cylinder off, and the fluid did shoot out of the front reservoir whenever I let off the brake. Saw negligible, if any, movement on the rear reservoir. Removed the fittings from the master cylinder and when the brake is pressed, fluid does come out of both openings, but it does shoot quite aggressively out of the front reservoir anytime the brake is pressed.

Let me know if there is anything else I can provide to help troubleshooting.

Thanks all!

 

[Ranger16]

I'm thinking probably collapsed rubber lines

That would be my first guess.