need help please with brake bleeding 63 c10

well i got the lines run and the new single master cylinder installed. went to the rear right wheel and cracked the bleeder screw and used the mutyvac to try and pull the brake fluid through. after about 15 mins i still get nothing and the level in the master cyl has not changed. i see that if i turn the bleeder screw more than 3/4 of 1 turn, a little brake fluid seeps out. same with rear left wheel.

also when i looked at the master cyl plunger, i have to push the brake nearly to the floor before the brake rod really starts to actuate the master cyl. there was no fluid in the system before so maybe this will "fix itself" when all the lines are fully bled? i triple checked and dont see any leaks anywhere.

am i doing something wrong/missing something?

thanks in advance.
- jason

 

I bought a few weeks ago an air-powered ejector from Harbor Fright - worked damn good! That said change out your bleed screws as they are probably filled with crap and buy an extra to drill out as shown for easier bleeding. Also, get a gallon of fluid, don't screw around with quarts...

 

can you explain that better?

Are you just looking at the plunger rod with the black boot still on?

What you want to see, with the boot pulled off to one side; is that the piston is all the way back, and that the plunger rod should start to move the piston with maybe 1/2" of movement on the brake pedal pad.

answer please

 

did you bench bleed the new M C ?

 

Make sure there is just a little bit of free play in the pedal, so you have to push it a little bit and then it starts to push the piston in. Like F&J says.

Make sure the tube nuts are all TIGHT, use a flare wrench. If you see any fluid leaking out anywhere, then air will also leak in there, and keep you from being able to bleed the brakes fully.

Have a helper push the brake pedal....it really does work a lot better with two people. My method is to get the helper to push the pedal 3 times (slow pumping then hold it down), then I open a bleeder, let the air/fluid out, and have them do it again, repeat. After several tries be sure to fill up the m/c with fluid again. When I get mostly fluid out of one bleeder, I move to the next. After I get some pedal, I usually go over each one again, having the helper just slowly push the pedal down while the bleeder is open, then I close the bleeder and have them release the pedal. Check for any air bubbles, if there are some then repeat until it runs clear.

When this method doesn't work, it's always because there's a leak, or I didn't bother to rebuild the master cylinder, or something.

Also make sure to adjust the brakes themselves, it's hard to bleed them when they are too loose, as the pedal will always go to the floor.

 

No helper? here is the way I do it. Nobody ever shows up until I am finished

That is a real easy cyl to bleed if there is "that free-play" at the rod. That can be adjusted under the dash with 2 wrenches.

With that done, loosen the single line on the front of the master, a half or full turn.

Move the brake pedal down, but don't let it come back too fast. Do this slowly till you hear fluid or bubbles spitting. when you get good fluid there, tighten that line.

You now throw the repair manual away and open the driver front bleeder about a half to one full turn. Now slowly work the pedal, without letting it go back too quickly. It should start to flow. Tighten that bleeder when you think it's running fluid with no air. You can work the pedal with a long stick while kneeling and trying to see that bleeder....or at least see fluid hitting the floor..

Then do the rt front, and then go to a rear one. and then the other rear.

This always works for me on single circuit brakes.

If for some reason, you can't get fluid out of the first wheel cylinder, after you bled the master, you can bleed it at the T where the two front lines meet the one from the master. Then go try a front, it will work then.

 

thank you all i actually just got back from HF picking up the air vaccuum gizmo. i rebuilt the brake lines on my 67 dart from scratch with no issues yet this one is giving me fits lol.

what i was trying to explain was that i installed a brand new master cyl which i had bench bled first. i hooked it up after examining all the lines/junctions etc. pushed the pedal down a few imes and found 2 leaks - 1 at the fitting at the master cyl and 1 ata junction i needed to join 2 lines. i used flare wrenches on all and tightened them up and no leaks.

so i started at the rear as i had been told years ago to do. bleeder valve opens/closes freely but after 15 mins o using a mityvac i got nothing.

i then went and looked at how the rod from the brake pedal was actuating the piston in the master cyl. the rod does not engage the piston until i have pressed the pedal about 2 inches from the floor. i am guessing this is since there is so much air in the system?

i read that adjusting the free play of the brake rod can throw off the ratio of the brake action and thus dont do it? something about the ratio of how much pressure is exerted vs how much travel?

 

The free play will not affect the ratio. the ratio is determined by how far the push rod is from the pedal pivot.

If the push rod is too short, then the piston won't have full travel, and you'll have a lot of trouble bleeding the brakes.

 

if you still have your old master have a look where the brake rod goes in, see if it looks different then your new one, sounds like it is.

 

There are two styles of 63 masters, one rectangular and a round cover. One has straight across bolt pattern, one is angled pattern. But from what I recall, they interchange with no mods? I think both patterns are on a 63 firewall.

I don't know why the rod would be that far off on adjustment....except if the rubber bumper for pedal return stop, fell off. Then the pedal would come back further, and seem to have too much freeplay.

 

Ok on post 7. The piston may be stuck down the bore of the master cylinder for some reason. Or you have the wrong master cylinder and the hole in the end of the piston is quite a bit deeper than the one in your old master cylinder's piston. If you have the old one compare the depth of the hole that the pushrod goes in on each.

If you have the Vac pump hooked up correctly and haven't had any fluid come through in that period of time you are probably sucking air somewhere or flat have it hooked up wrong. Are you getting a vacuum reading when you pump the lever on the pump that might show that the fitting is blocked?

I used mine hundreds of times until a former boss backed a loader over it and always got fluid to come through the system. But sometimes if the bleeder was too loose I sucked air in around the threads of the bleeder screw.

Pull each bleeder screw and make sure that you can get air or fluid through them. They often get filled up with rust or mud if they don't have the rubber plugs on them.

If you have a helper available that can follow directions it is still simpler to bleed them the old fashioned way as Jim suggested in post 5. Have the helper pump the pedal VERY SLOWLY, have them hold the pedal down, open the bleeder, let anything out, close the bleeder and then tell them to pump it again. Check the fluid level often to make sure you don't run out.
My daughter started pumping the brakes for me when she was 4 years old and she still is one of the best at it of any helper I have had before or since.

 

Wow.

 

i checked the master cyl and there are 2 diff bolt hole setups. the one i got has the round cover and the stock one was more of a square. mine mounts directly side to side while the old one was the one with angled bracket. the old's push rod is seized in the "on" position - akak jammed all the way forward and it wont unstick so i just got a new one. the new one's piston moves freely and seems to work fine its just not engaging early. ill take it off tomorrow and see what it looks like. i know the old one appears to go in more towards the firewall than the new one - maybe i am supposed to swap a part over or something?

 

just realized also that the new master cyl didnt come with any brake pedal stop things? ill try and take a pic but essentially the brake rod just kind of goes into he piston and thats it. i am prob just over analyzing things lol

 

have you ever worked on brakes before.make sure the person helping you is paying attention to what you say(i gave up on getting my wife to pump the pedal).if you replaced lines it will take a while to bleed all the air out.i upgraded my 64 to a double master cylinder .i fill better pulling my trailer with a double instead of a single master cylinder

 

you really need 2 people, if your worried about the person not understanding what you need then try this. FIRST make sure everything is tight and the master is bench blead, second get a small glass jar and some clear tubing. Fill the jar about 1/4 full of brake fluid, put the clear tubing OVER the bleeder and into the jar (making sure the end of the tube is submerged in the brake fluid), crack open the bleeder slightly and start pumping SLOWLY. You'll need to keep checking the master so it doesn't go dry, once the air bubbles are gone, close the bleeder and move to the next wheel.

Not to get off topic but, you know if your not doing a resto and you want a dual chamber master one from a '67 will bolt right on. All you need to do is re route some brake lines, run 1 new one and use 2 line adapters.

the pic is of my '64 panel

 

yeah i have done brakes before and it was not a huge deal. an hour or two and i was done. all new lines front to back. this one im not getting.

i just took apart the stock master cyl. basically i can get the piston to move up/down but when i add brake fluid the piston gets stuck when i try to bench bleed it. i cleaned the inside good, cleaned up all the gunk etc cleaned each individual art and repeated the bleeding. same thing 3 times. no idea what is going on with it.

 

i'm usely by myself bleeding brakes, i have a multi-vac, i built a pressure bleeder, but what i use now is a stick and a couple nice strong bungy cords, i have a wooden stick about 3ft long that i place one end on the brake pedal and the other near the bottom of the steering wheel, your stick should go a foot up beyond the steering wheel, i take the bungy cords and hook one end on the steering wheel up over the end of the stick and back down to the steering wheel, i like the heavy rubber bungies, now i slide the stick off the pedal and pump it a few times, then with the pedal pushed down i place the stick back on, its kinda like a bow and arrow effect, works like a charm.

 

If you are using the HF vacuum bleeder and the gauge shows a steady vacuum the bleeder is plugged. If you are showing no or little vacuum then you are pulling air. If the bleeder is out to far you are just pulling air around the bleeder screw.

 

When bench bleeding don't push the piston all the way, a 1" stroke is sufficient for bench bleeding--- with no helper for the whl cyl bleed, jam a stick/ prybar between the seat and pedal cycle 4 bleeds and refill...works for me.
Bench bleeding can be done with a return hose or even plugging the port.

 

Is this a rebuilt new cylinder? The last one I bought was maybe 8 years ago at Carquest, it was maybe $13 with a core.

 

i have both a new master cyl and the stock one. figured id see if i can save the stocker. the piston was stuck so i took it apart and cleaned it good. i cn get the piston to actuate fine if there is no brake fluid in it but as soon as i add fluid the piston gets stuck and the brake fluid gets warm - even just during a bench bleed.

i went to the truck and adjusted the brake rod and it needs to be nearly all the way extended to get the rod to engage the m/c piston. its better but still seems odd to me.

the stock master cyl seems to go thru the firewall and extra inch or so compared to the new master cyl. i get comensating for this by extending the brake rod out but seems odd to me. thats why i tried to save the original master cyl - give me more brake action - but cant figure out why the piston gets stuck when you add fluid? maybe the vaccum is not working properly to let the piston return?

 

duh well i think i am just an idiot

i needed this type:
http://www.ecklerstrucks.com/chevy-...le-with-automatic-transmission-1960-1962.html

but got this type:
http://www.ecklerstrucks.com/chevy-truck-reservoir-brake-master-cylinder-round-1963-1966.html

note the diff length of where the brake rod enters the piston.

going to try and find this kind. idiot.

 

damnit sorry to keep bumping the thread but i am way confused my truck is a 63 with 4 speed manual and had in it the square master cyl. according to autozone etc i should have the round one for my year/trans, yet the truck has the square one. there is def a diff in length of brake rod tunnel? why would this matter with a manual or auto trans? sorry for the continued posting just dont want to waste a sunday trying to bleed brakes for no reason if the equipment is wrong?

 

I have a '65 C10 and I'm not sure if there is a difference in the ' 63 vs. the ' 65 models as far as brake line routing ? I know you're supposed to start bleeding from the farthermost wheel cylinder working to the nearest ? I don't know if this applies to a ' 63 C10 but on a ' 65 C10 , the left rear wheel cylinder is the farthermost away from the MC. The brake line comes down from the MC , tee's ( on the front cross member ) to the left front then to the right front , then down the right side of the frame to the rear axle where it drops down to the axle and tees off to the right rear brake then across to the left rear brake . Not sure if this would make a difference in your particular situation but thought I'd mention it ! Also , my ' 65 C10 has the round MC as had been mentioned and I have replaced it with one from Autozone .

 

going to try it with the new one. the new one ia a 1 in bore the old one was a 1 1/8 bore. what does this mean?

 

Don't buy a gallon of brake fluid unless you are going to use it all at the same time! Just buy it by the quart as brake fluid will draw moisture if you store for a period of time after it has been opened.

 

The smaller bore will apply more pressure to the wheel cylinders with the same force from your foot.

If a bore is too small for the wheel cylinders, then there will be a lot more movement on the brake pedal to stop the truck, so you need the brakes adjusted well.

There should be bore specs for the correct 63 cylinder on some truck repro parts sites?

 

what is the bore of your wheel cylinders?

 

hi newbee here. does your c10 have power brakes , if yes then it could be your booster cylinder is partially frozen not allowing the rod to move freely.it sounds like it could use dissasembly , cleaning and lubricating. just did one on my 57 and it sure helps the bleeding process if the brake rod wants to follow the peddle