Bench bleeding help

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OllieDemon45

OllieDemon45

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Once i have the Master cylinder bench bled.. do i put the pushrod back on since the the rubber hose and bracket get mounted on the master cylinder too. Than attach the brake lines.
Hoping this doesn't take too long and get air back in the master cylinder.
I have the stock push rod and also bought a new gasket/seal for it from Dr. Diff.
 
OllieDemon45 said:
So basically I’m using the pushrod to bleed it?
Click to expand...

Yes, you can bench bleed it on the car, but it must be level, so you may need to jack the car up to level the MC out. You do not pump the MC several time like when you bleed the system. If you have the little rubber hoses you can. Just put them into the MC reservoir and gently pump the pedal until you don't see anymore bubbles. Than it's bled.
 
I bought the bench bleed kit so i have the hose and clamps to make it easier.
I guess it's time to hook up the push rod and connect it to the brake pedal and gets things done. Hopefully i'll have it done tomorrow.
Thanks for the help
 
OllieDemon45 said:
I bought the bench bleed kit so i have the hose and clamps to make it easier.
I guess it's time to hook up the push rod and connect it to the brake pedal and gets things done. Hopefully i'll have it done tomorrow.
Thanks for the help
Click to expand...

You're welcome. It's important to get it level if you do it on the car. If the nose is high in the front, you'll never get the air bubble out.
 
OllieDemon45 said:
Once i have the Master cylinder bench bled.. do i put the pushrod back on since the the rubber hose and bracket get mounted on the master cylinder too. Than attach the brake lines.
Hoping this doesn't take too long and get air back in the master cylinder.
I have the stock push rod and also bought a new gasket/seal for it from Dr. Diff.
Click to expand...

I always bench bleed master cylinders in my vice and tap the MC with a small hammer to help dislodge any small air bubbles. A large phillips head screw driver works well to fully depress the plunger too. I also tip the MC nose down a few times to help displace the air. If I come back to it about an hour after bench bleeding it, I always seem to get a few more bubbles out of it.
 
I always use a #3 Philips with a comfortable handle to bench bleed.

I clamp one of the MC ears in a bench vice.

I use twist ties to hold the hoses via the bail (if it has one), and I leave the hoses attached wile installing the MC in the car, and then swap them for the metal lines one at a time- real quick like.

You can also put the lid on to create a vacuum lock while holding the bleeder hoses higher then the reservoirs.
 
YY1 said:
I always use a #3 Philips with a comfortable handle to bench bleed.

I clamp one of the MC ears in a bench vice.

I use twist ties to hold the hoses via the bail (if it has one), and I leave the hoses attached wile installing the MC in the car, and then swap them for the metal lines one at a time- real quick like.

You can also put the lid on to create a vacuum lock while holding the bleeder hoses higher then the reservoirs.
Click to expand...
So as long as the hose is above the bail, no air can get in I assume. This gives me time time attach the push rod assembly.
 
So here is the assembly, does it matter what direction the seal goes? I see there is a small “v” cut out on one side, should that be up or down or does it not matter?

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I have found the best way to install the rubber grommet into the MC, is to use a long socket the size of the grommet and simply tap it in, or push it in until it bottoms out. Once that's done, install the MC and its 4 nuts. Next, install the push rod to the brake pedal. Put a little lubricant (wd40) on the end of the push rod, and put it into the MC. Give the brake pedal a push, and it will pop into the grommet. Install the rubber dust shield.
 
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I use the vehicles push rod to bench bleed a master cylinder in my vise. A piece of 2X4 about a foot long, wrapped in shop towels, held against my chest. Push rod against that. Left hand grabs back of the vise. Lean in and away to stoke it! Too easy. Power brake master cylinder is same except a long drift pin substitutes the push rod.
Master cylinder ports are going to dribble fluid, so by the time I get the line fittings tight any small air bubble in top of the line bled away. Check brake lamp switch adjustment. Done
 
Now it doesn’t fit through the firewall with everything hooked up. This has been a fight every step of the way.
New nickname “Demon Child”

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