No brake pressure

[abentz]

82 Brat. I finally replaced most thing I needed to get the thing going, then realized my brake pedal goes to the floor. 

I have read some forums about bleeding the brakes, and I have been trying to do that. I did it from RR LF LR RF. The back ones seemed to bleed just fine, but I am not really getting much fluid out of the front ones. Cleaned out the bleeders best I could, still not much. 

Any suggestions on where to continue? Replace master cylinder? 

 

[el_freddo]

Start by adjusting the rear shoes.  These are done manually via a small square headed bolt that could be covered by a rubber boot. Many lose this boot and are more than likely seized. 

Cheers

Bennie

[djellum]

how are you bleeding, having someone work the pedal, gravity, vacuum pump?

 

did you replace the front brakes?  if so how did you open up the caliper to reset it for new pads?

ive had them take a bit of doing, you think theres no more air but then you find a big bubble.

[abentz]

11 hours ago, el_freddo said:

Start by adjusting the rear shoes.  These are done manually via a small square headed bolt that could be covered by a rubber boot. Many lose this boot and are more than likely seized. 

Cheers

Bennie

Ok, I will look into this. Thanks!

[abentz]

3 hours ago, djellum said:

how are you bleeding, having someone work the pedal, gravity, vacuum pump?

 

did you replace the front brakes?  if so how did you open up the caliper to reset it for new pads?

ive had them take a bit of doing, you think theres no more air but then you find a big bubble.

I am working the pedal myself, with the occasional help of a friend. 

I did replace the front brakes, to open the calipers I used a kit from Autozone and twisted the calipers into the pistons. 

How long are you talking for a bubble to come thru? 

To clarify, the brakes aren't just soft, the pedal goes down to the floor easily every time. 

Thanks for the reply. 

[skishop69]

You can't bleed brakes on your own unless you have a check valve bleeding hose. Without that, someone has to pump the pedal 3x and hold on the third while the other person opens the bleeder screw while holding. Close the screw and then release the pedal. Repeat until no air comes out of that circuit.

[Jmpjose]

Make sure you have a vacuum line to master cylinder. Break pedal will sink to floor if this is disconnected. This happened to me  

[jono]

Bleeding on your own is possible but need an old plastic bottle with hole in its lid for clear PVC hose from bleed nipple. An air breath hole in lid is also handy. I use an inch of rubber hose to fit tightly over nipple and PVC hose at its other end. Trick is then to have upward travel up before then drain down into bottle. This way you can monitor any air bubbles coming out and helps reduce/prevent air sneaking back in while not looking.

This way you can go blast pedal as required. No need to buy one man bleeder valve kit

 

[el_freddo]

3 hours ago, Jmpjose said:

Make sure you have a vacuum line to master cylinder. Break pedal will sink to floor if this is disconnected. This happened to me  

 

Ive never heard of this being an issue. Without the power assist vacuum line the brake will operate about the same as trying to push a brick through the floor when properly bled.  That meaning the brakes are only as good as your leg strength. 

@abentz The rear brakes may need adjusting but this isn't the root cause of the issue.  If you've swapped the calipers or renewed the seals, it can help to fill the calipers with brake fluid as best you can prior to install.

You definitely need a second person that doesn't mind doing the boring task of listening to your calls as you bleed the brakes OR use one of those self bleeder kits. You've still got loads of air in the system or you need to bleed the master cylinder. 

Cheers

Bennie

[abentz]

On 7/21/2018 at 11:28 AM, skishop69 said:

You can't bleed brakes on your own unless you have a check valve bleeding hose. Without that, someone has to pump the pedal 3x and hold on the third while the other person opens the bleeder screw while holding. Close the screw and then release the pedal. Repeat until no air comes out of that circuit.

Ok, so I went back and bled all of them the right way, as you described. I did not see much air in the system, but bled each brake for a while. 

I am beginning to think now that the master cylinder could be at fault, bc there seems to be no air in the system.

Thanks for the reply, and bare with me as I am learning new processes. 

[djellum]

did the brakes pump up and hold until you opened the bleeder or was it 3 to the floor and no pressure?

have you checked that the brake pedal is actually attached to the master?

did they work before this?

 

[abentz]

On 7/21/2018 at 3:43 PM, Jmpjose said:

Make sure you have a vacuum line to master cylinder. Break pedal will sink to floor if this is disconnected. This happened to me  

Everything looks connected to me. 

[idosubaru]

 

On 7/20/2018 at 11:25 AM, abentz said:

I have been trying to do that. I did it from RR LF LR RF. The back ones seemed to bleed just fine, but I am not really getting much fluid out of the front ones. Cleaned out the bleeders best I could, still not much. 

The master cylinder is moving fluid, subaru MC's fail so rarely I wouldn't replace it without compelling evidence which I don't see so far here. 

if the system was opened it will take FOREVER to bleed.  in some cases i've used two large cans to bleed a completely open system before.  if you're toying around with a tiny amount of fluid and little bottle you're probably not bleeding it enough.  also if you let it get too low while bleeding it sucks in more air and you gotta start over. 

you may be introducing air as you bleed, we can't see how you're doing it or the condition of the screws. 

if you have bad bleeder screws - replace them. 

***What is the history of the brake system?  Have you ever known it to work properly?  Has it sat unused for 30 years?  was it previously worked on?  was it low on fluid?

Edited July 23, 2018 by idosubaru

[abentz]

6 minutes ago, idosubaru said:

 

The master cylinder is moving fluid, subaru MC's fail so rarely I wouldn't replace it without compelling evidence which I don't see so far here. 

if the system was opened it will take FOREVER to bleed.  in some cases i've used two large cans to bleed a completely open system before.  if you're toying around with a tiny amount of fluid and little bottle you're probably not bleeding it enough.  also if you let it get too low while bleeding it sucks in more air and you gotta start over. 

you may be introducing air as you bleed, we can't see how you're doing it or the condition of the screws. 

if you have bad bleeder screws - replace them. 

***What is the history of the brake system?  Have you ever known it to work properly?  Has it sat unused for 30 years?  was it previously worked on?  was it low on fluid?

Ok, I will try and bleed the system more. 

The bleeder screws seem fine to me, I picked out any debris that was in them and they are letting fluid pass through.

History of the brake system- I just bought the car 2 months ago after knocking on someone's door asking if the Brat sitting in their driveway was for sale. The car had been sitting there for about 3 years awaiting a new hub that had stripped. The brakes were removed from the rotors for most of that time I am assuming. The handbrake seems to work just fine. That's really all I know about it for now. 

[1 Lucky Texan]

no sign of brake fluid dripping anywhere?

 

does kinda seem like master cylinder could be at fault - very old car, sitting unused for a long time....add full travel pedal excursions and I could see the MC seals being bad.

[abentz]

1 hour ago, 1 Lucky Texan said:

no sign of brake fluid dripping anywhere?

 

does kinda seem like master cylinder could be at fault - very old car, sitting unused for a long time....add full travel pedal excursions and I could see the MC seals being bad.

The only place that looks relatively damp is where the master cylinder and the brake booster connect? I have attached pictures, but can't really see much in this photo.

Another thing I keep wondering about is what appears to be a part a piece of steel brake line that I have found in the engine bay. After following the brake lines I cannot see where it would connect, but maybe I am missing something. Photo also attached. 

[1 Lucky Texan]

I am unfamilar with models as old as yours - could brake fluid be pooling on top of the fuel tank or inside a crossmember or ????

Edited July 23, 2018 by 1 Lucky Texan

[john in KY]

Problem could be the hill-holder if so equipped. 

[idosubaru]

that master cylinder has bleeder screws on it and i've never seen that on any 1980's EA82, ER27, or 1990-present EJ, EG, EZ subaru's so you might want to make sure you're bleeding it right or otherwise understanding what part those MC bleeder screws may, or may not, play in it.

 

LT has a good point - do the brake lines go above the gas tank and is there any rust under the vehicle?

like LT said two posts ago - an initial leak will be just enough for the pedal to do what you're describing but you won't notice a leak until it springs huge and gushes out from over the gas tank if they're routed above it.  so if it's got some rust back there and the lines go above the gas tank this is possible.  the fluid will just pool up on top and get absorbed by years of dirt and dust and takes a good bit before it finally will start running down the sides or it blows a larger hole through the rust and starts spraying further and larger quantities. 

[djellum]

did you bleed the master cylindar, that should be what those nipples are for.  

as stated above make sure the hill holder isnt engaged, most people unhook the cable and just turn the lever by hand and it should stay open.  cant imagine it would do anything for your problem unless the holder is leaking but just in case.

the reason for bleeding is that air compresses and fluid doesnt, so if you have enough air in the system it will compress a lot.  it will still dribble out cause the pressure increases but its nowhere near enough give you any pedal.  Ive gone 3 or 4 pressure bleeds with an assistant before getting any pedal at all.  and Ive bled solid powerfull streams of fluid multiple times only to get another section of air.

can also check for leaks at the wheel cylindar in the rear drums.  can leak there and the drums contain it.

if you really cant get someone to help you pump them then either hook up a vacuum pump and bottle setup (just a cheap harbor fright one is fine and inexpensive), or get a long pipe and depress the pedal and wedge the pipe against the seat to hold it, then go open up the bleen nipple, rinse repeat.

its hard to say witout seeing it, how much fluid has it taken total through the process?

[djellum]

is that hill holder hooked up right?  it should have the lines from the master cylinder going into it (maybe just one though my later model has both), then from there 2 lines out to a distribution block that changes the pressures front to back.  that block should have 2 lines out for rear and 2 lines out for front.

not 100% on what an 82 actually has, but the hill holder needs to intercept at least one line so it can lock it, and there should be a metal gizmo of some kind in the motor compartment that the final 4 lines leave from (the disc and drum brakes need different pressures) 

im wondering what that line that goes from the hill holder to the outer side of the master cylinder is doing?  looks much cleaner that anything else around it.

[el_freddo]

You guys got the hill holder on your BRATs? Our Brumby equivalent over here never saw a hill holder fitted from factory.  That only occurred on the L series onwards. 

As for the state of the master cylinder I'd say clean it up and see if you can see any fresh evidence of leakage. If it is in fact leaking fluid between it and the booster it's time for a new master cylinder. 

I'd find a willing volunteer to help you bleed these brakes. Select a brake fluid that is a different colour to what you have now, run the old stuff until low then too up with the new stuff. Bleed until the new colour comes through. This should indicate that no air is in the system if bled correctly. 

I'd start by bleeding the MC if possible then follow the sequence you've already been doing. 

That line you've got could be a spare or some odd part from another vehicle that's giving you a bum steer.  I also doubt the brake line, or any for that matter, pass over the top of the fuel tank.  

Cheers

Bennie

[abentz]

18 hours ago, idosubaru said:

that master cylinder has bleeder screws on it and i've never seen that on any 1980's EA82, ER27, or 1990-present EJ, EG, EZ subaru's so you might want to make sure you're bleeding it right or otherwise understanding what part those MC bleeder screws may, or may not, play in it.

 

LT has a good point - do the brake lines go above the gas tank and is there any rust under the vehicle?

like LT said two posts ago - an initial leak will be just enough for the pedal to do what you're describing but you won't notice a leak until it springs huge and gushes out from over the gas tank if they're routed above it.  so if it's got some rust back there and the lines go above the gas tank this is possible.  the fluid will just pool up on top and get absorbed by years of dirt and dust and takes a good bit before it finally will start running down the sides or it blows a larger hole through the rust and starts spraying further and larger quantities. 

The brake lines do not go above the gas tank. They look pretty good, can't see any rust surprisingly.

[abentz]

I bled the system more this time using a bottle with brake fluid in it with the hose running from the bleeder valve into the bottle. 

I got really good flow and air out of the system on all but the right front. It seems clogged? or it is just not getting any pressure. 

Next step when I get back in town in two days will be to bleed the MC. I will also check the hill holder. 

[idosubaru]

15 minutes ago, abentz said:

I bled the system more this time using a bottle with brake fluid in it with the hose running from the bleeder valve into the bottle. 

I got really good flow and air out of the system . 

This is tough because bleeding is relatively simple but has some very particular details sometimes and you're working on an unknown vehicle...!!??!??

More than likely there's still air in the system. 

Take note - everyone was saying bleed the brakes - and you were guessing master cylinder multiple times. 

You reassessed your bleeding and got more air out - so those suggestions were spot on. 

I'm not sure where the line is drawn between "you need to bleed more" and "it's probably something else" - that's a very gray area - but it's often the case more bleeding or proper bleeding or a better bleeding set up (don't run out of fluid in MC, screws not leaking, hose/pump/whatever make shift system is being used working well)....