Projects Brake bleeding is making me crazy

I completely re-lined the brakes on my '59 Rambler and installed a remanufactured dual system m/c that I completely bench bled. New wheel cylinders and spiffy new front disc setup. Nothing leaks, yet I can't seem to get all the air out!

Bleeders are on the north end of the calipers and I've been starting from the farthest and working to the closest. It looks like, when I pump the brake, I'm getting out all the air - but still have a mushy pedal.

A friend told me to pump the pedal about half-way down and hold it there with a stick against the seat overnight, to let small bubbles work their way up to the m/c. Not going past the 'second hole' in the m/c - so those bubbles can escape. Ever tried this? I'm going to give it a shot today.

 

I have a OT car that I put disks on and couldn't get the air out. My son's friend said to open a bleeder and have some push the pedal down to the floor and hold it then tighten the bleeder. Did that several times on each bleeder and I had a good pedal been good since.

Jim

 

Look closely at All connections. Any leaks will induce air into system
Make sure shoes adjusted properly
Honestly this is the way we bled the brakes, on our IMSA Porsche while I was a professional race mechanic
Simple plastic bottle with clear hose. Drill hole in top and insert long length of clear plastic hose, all the way to bottom.
A string and zip tie help hold it, if solo.
Start at furthest wheel, attach hose to open bleeder and bend hose upward in a loop. This so you can see all the bubbles
Slowly pump pedal with bleeder open, until solid stream of fluid. Snug bleeder and move on to next. After all 4 are done, you can do a pressure bleed just to be sure.
Normally I’m working by myself so this method works fine.
Pressure bleed does require 2 people.
Good luck


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Got rear drums? Make sure the adjustment is good. Sometimes I'll over-adjust them a little just to make the bleeding go easier, back them off after. There really are NO tricks to bleeding brakes and pumping them with air entrapped only makes them more air-bound.

On my Ford, I used a vacuum bleeder for the first time and it made things easier. In shops I've used pressure bleeders for years. They always made bleeding short work.

 

Thank you, Guys!

 

I use the low pressure bleeding technique. I got a garden sprayer to connect to the master cylinder cover to keep a slight pressure to push the fluid through the system. Pumping the brakes to bleed them allows air bubbles to travel back and forth in the line. The constant pressure pushes them through. I didn't bother to set it up to use fluid but there are many YouTube videos on that. I just fill the master. Replacement caps are available for some master cylinders to put a tube in to connect the hose. It only takes a couple of psi.

I used it on a newer truck with antilock brakes. The antilock brake valve makes them a pain to bleed but the low pressure did the job easily.

 

Can make you crazy! Agree with all posts so far. But we don't know exactly what Tom is doing when 'pumping ' the pedal - can mean different things to different people. Long, fairly slow presses (maybe 2 to 3 seconds to go down?) to the floor followed by equally slow pedal return always works for me. Some folks stamp hard and rapidly as if they're trying to put out a fire!

Chris

 

Is your mastercylinder under the floor?
Are you using residual pressure valves?

 

Done that many times and had your problem just as many times! Finally figured out after many of the many times it wasn't wheel brake adjustment (usually had them so closely adjusted, could hardly turn the wheel), and was not the fluid/air problem. Many times it was the adjustment of the push rod in the master cylinder. It is surprising how little adjustment of that rod can make the brakes rock solid or totally non-functional.

 

Check put "Speed Bleeders". They make it an easy, one-person job. I always had a real tough time getting the brakes on my '67 Corvette bled. Since I installed the "Speed Bleeders" I have had no problems.

 

Tom, one tip that I picked up along the way somewhere's or another might help, and can't hurt. The rear axle is a drum setup if I'm reading your post correctly.

These are very often adjusted incorrectly as drum systems are somewhat obsolete and the knowledge base on these recedes back, left only in the minds of old dodderers like myself.

Prior to bleeding, the star wheel & shoes should be ran up as tight as they will go on the drums, so they don't turn at all. Then proceed with the bleeding. I think the idea here is that the wheel cylinder pistons can interfere with the inlet port during bleeding. It does seem to make for maximum volume of brake fluid in the cylinder anyway. Depress the brake pedal after bleeding several times to center the shoes and take up any clearance or "slop" in the linkage. Then, back off the star wheels to the point where the wheel will spin, not quite freely but with a "light drag".

Incorrectly adjusted brake shoes will have a low, mushy pedal that feels very much like air or bubbles in the system. It may take an iteration or two as they start to wear in. Take a short drive or two around the block. For best results the shoes and pads need several repeated moderate braking to get them up to temperature, to burn off the resins and binders. You can smell 'em. Otherwise they tend to glaze over.

p.s. Say hi to Van & Bonnie

 

The bleeders need to be at 12:00, straight up and that may be different than the "north end"

 

Also do not assume that the M/C is good there seems to have been a lot of bad "new" master cylinders over the last couple of years.

 

I'm one of 'em! On my 32 sedan build I COULD NOT get consistent pedal, from some to none. Couldn't drive the car! Must have bled them two dozen times! Changed out the supposedly rebuilt M/cyl and BINGO.

 

If you have a helper working the pedal, they need to be trained. Some people mash the pedal to the stop. It takes a measure of finesse especially the last round of final bleeding. I usually have a great pedal after the 2nd time around.

 

I know right !?!

 

Also, if you are using silicone brake fluid, I read that it is somewhat mushier than DOT4

 

It's all in how one see's it.

 

I got a 1958 rambler which I changed to a duel piston setup. I usually place a rubber hose on the bleeder and then into a clear jar full of fluid. I have someone push on the pedal and I open the bleeder and the bubbles come out into the jar and once they are all out and the hose sucking the fliud back up, I close the bleeder. It seems to work every time but then again I still have an all drum system.

 

Military time clock.
so when "they " being THEE military say "watch your 6" or "bogie at 3:00"
They are not referencing a 24 hr clock.

 

All joking aside. Is the master above or below the equator on this type of vehicle?

 

Actually, it a Rail Road invention. "Where's that darn train?" "Oops it arrived 12 hours ago"

 

Do you have thru frame line connectors? They can trap air.
Good suggestion above making sure the brakes are adjusted correctly prior to bleeding.

I just installed and bled my system. No bench bleed on the M/C, vacuum bleeder. No issues. I didn't pay that much for the bleeder and I have used it for many years on countless cars. It is a life saver...quite literally.

 

I usually bleed my brakes solo. I pump the pedal then wedge a 2X4 of a suitable length between the pedal and the lower seat cushion then crawl under the car and loosen the fitting with a hose in a clear bottle.
Lots of going back and forth but good exercise.

 

I did the same for the first time with OT newer truck when I swapped to stainless lines. I bought a 1/2 gallon hand garden sprayer at menards for a few bucks.

Good set up. Had a pressure bleeder on the feed side and vacuum bleeder at the wheel. Got it done in no time, first time, and didnt have to ask anyone to pump. That alone is worth the price of the equipment.

 

"Check 1800" just doesn't roll off the tongue the right way.

Bobby Bare didn't sing "I'm 804.672 Kilometers From Home"; for a reason.

 

"She left on that 5-0-9 Eastern standard blue time"

 

You didn't mention if you are using metric calipers.
Certain years of those are "low drag" style which means the piston retracts farther to prevent the pad from rubbing the rotor.
These require something called a "quick takeup" master cylinder.
Those look pretty ugly, so you need to make sure you don't get the low drag calipers...and then you won't need one!

Seriously though...the low drags don't work with a regular master so you can bleed them until the cows come home and still get nowhere. The first pump is required just to get the pads back out to the rotors!

 

Could you elaborate on this method a bit more? I am just not seeing it in my mind. I am not a gardener so that is one drawback to visualizing it.