[Pecosbill]

Installed all new brake lines, new master cylinder and had the booster rebuilt. They're all currently dry as a bone, but tomorrow I'm planning on filling the master cylinder and bleeding. I've read some about "bench bleeding" the master cylinder and wondered if that is necessary if my replacement master cylinder has a bleed valve on it.

Also, the 1964 Pontiac shop manual says to bleed the left front (closest to MC) first then gradually work back to end up with the right rear, the furthermost away from the MC. But I've seen on this board where others have said to start with the one furthermost away and work back towards the MC. I'm tending to go with the manual but would like to hear what others have to say.

[Terry Gartner]

Personally I've always bench bled the master first and then worked furthest away from the master.

It seemed to work out for me.

[Tempest]

Yes, you need to 'bench' bleed the master. There is no "bleed valve", but I always use the 2 clear plastic hoses that come with the master. Screw the plugs into the outlets, place the hoses into the brake fluid in the master, and pump until there are no more bubbles. That's all.

I have always started at the wheel furthest away from the master and worked my way to the closest wheel. (Right Rear, Left Rear, Right Front, Left Front)

It may take a while to get the fluid to the wheels, (with brand new dry lines) so don't let the master go dry, or you will have to bleed it again.

[Terry Gartner]

One of the best ways to get it started is to put a hose on each bleeder and put the hose end in a cup (so you don't make a mess - if that's possible); It takes a while, but start furthest away as stated before; open the bleeder and let gravity pull it through. Once you see the clear fluid come through the tube, shut that bleeder and move to the next one closest. Otherwise whoever your friend is pumping the brakes might quite helping, that's usually my wife and pumping the brake pedal isn't one of her favorite chores.

The little vacuum pumps are of some help too.

[Pecosbill]

Thanks, guys. Look at this photo of my MC. Notice the bleed screw. What is its purpose?

[61-63]

You do not need to bench bleed the master or bleed the master first just fill it up, put the top on, and start bleeding the wheel cylinders. Go back to the master frequently however and keep topping it off because the level will drop quickly as you push or pull (if you are using a some sort of vacuum on the wheel cylinders) fluid through the lines, especially the right rear when you first get started.

Within the past three months I put new lines and/or brake components on both a '63 Catalina and a '67 Fairlane and didn't bleed the master on either one I just filled the master up and got after it. On the right rear I had my wife pump the pedal up only four or five times and then I would top off the master cylinder again. Same with the right front.

Like you I read where the chassis book says to start with the closest wheel and I may try that next time just to see what happens. The shop manual also says to not rebuild
the master or wheel cylinders because honing them removes a special hard surface put in the bores when they were manufactured but I've been rebuilding/honing them all my life with no adverse affect.

Use DOT 5 fluid and you don't have to worry about it taking paint off. I can't tell any difference between the DOT 3 that was in the brake systems originally and the DOT that is in now we will see if I feel the same way a year from now.

[Old Goat 67]

Pressure bleeding is the only way I'll bleed brakes. Been doing it that way for 30+ years. One man operation, no mess, no waste, no fuss.

Watch this video and pay close attention to the reasons for doing it at the beginning. Mercedes guy but the video is very informative.

https://mercedessource.com/tech-help...ique-diy-tanks

My setup is not this fancy, but the basics are the same.

[Terry Gartner]

That's nice. How did you fabricate the cap for the master?

[Old Goat 67]

Simple is good for me.

C clamp to hold it to master, small regulator to control pressure at no more than 15 lbs from shop compressor, clear tubing to bottle at wheel, one wheel at a time checking fluid level in master, done in 20 minutes maximum, no waste, no mess, never fails!

You wouldn't believe the look on peoples faces when you do it on their vehicles.....

Charles

[65blackplate]

good idea old goat and the price is rite
thanks

[Terry Gartner]

Ditto

[salem1912]

I've had good luck with gravity bleeding first, then hold 1/2 way and crack the w/cylinder bleeders.

[Sirrotica]

45 years as a mechanic and I have always gravity bled all brake systems. I was taught by my father which started working on cars in the mid 30s and that is also the way he bled brake systems during his 45+ years repairing cars. It's the fastest easiest way with only 1 person required. Nothing to make or buy, can't beat free and easy.

It mystifies me why so many people want to make a really easy operation complicated. There are probably hundreds of posts on PY about bleeding brakes and almost as many experts telling how the latest vacuum/ pressure/pumping/ speed bleeders, way to bleed a brake system. Simple physics, fluid travels downhill and creates a siphon, that's all there is to it. I can bleed all 4 wheels at once and be done in under 10 minutes.

[rexs73gto]

I can say from the experience that if you want to get it done quick all you need is a clear bottle & hose & this is the way it was done on the Studebaker line. Fill the master , start with the rt. rear , put the clear line on the bleeder, open it up put the hose down in a bottle with brake fluid in it , have someone pump the brakes. As you pump it will push the air out & draw the fluid back in. Pump it about 4-5 times & that wheel is done. Go on to the next which is the lt. rear wheel do the same again until all 4 are done. Just keep the master full & the bottle full & you'll be done in about 10-15 min. It works great & you are assured that there is no air in the system, because the fluid is always present as long as the hose is in the fluid & the master is full because whether your pumping up or down it's either drawing in or pushing fluid out.

[geeteeohguy]

Sirrotica, that's what I've said over and over and over. Gravity bleeding has worked for me for the pat 35 years (I guess I'm a hair younger than you are!). Power bleeders, vacuum bleeders, pumps, etc....not necessary at all....at least on these cars. We ran into a Honda with ABS that required some special equipment to bleed out the modulator valve, but that was a late model that needed other work. You can lead a horse to water....

[rontiac]

^ ^ ^ ^ ^ ^ ^

Gravity bleeding all the way.......just have to set a timer, so as you're doing other things on the car while it's bleeding.......you don't forget .......and run the master dry!

(Don't ask how I know this...!)

[salem1912]

Originally Posted by Sirrotica

45 years as a mechanic and I have always gravity bled all brake systems. I was taught by my father which started working on cars in the mid 30s and that is also the way he bled brake systems during his 45+ years repairing cars. It's the fastest easiest way with only 1 person required. Nothing to make or buy, can't beat free and easy.

It mystifies me why so many people want to make a really easy operation complicated. There are probably hundreds of posts on PY about bleeding brakes and almost as many experts telling how the latest vacuum/ pressure/pumping/ speed bleeders, way to bleed a brake system. Simple physics, fluid travels downhill and creates a siphon, that's all there is to it. I can bleed all 4 wheels at once and be done in under 10 minutes.

Your just replacing air with fluid,most fluid will run down hill so if the M/C is at the highest point and the w/c are at the lowest point it shouldn't require all that fancy stuff. I see guys at work replace a wheel cylinder and 1.5 hr later they finally have it bleed(with the help of a second guy sitting in the car.WTF just put it on-crack the bleeder take the lid off the m/c wait for it to drip. tighten the bleeder push the pedal 1/2 way cracked the bleeder and a few bubbles will come out and your done.