Tips to bleed completely new and empty brake system?

1990 NA Miata non ABS

I just installed a new master cylinder, calipers, and ss lines. Hard lines were blown out. Entire system is effectively dry. 

I filled the reservoir and attached a Motive pressurizer thing at the master and used a handheld vacuum pump for good measure to pull fluid to each caliper. 

Next step is going to be a traditional 2 person bleed. 

The brake pedal still feels soft. Figured I'd ask for tips and input on whether I'm on the right track as I've never dealt with a totally dry system before. 

Thanks!

Bench bleed the master before installing. 

dean1484 said:

Bench bleed the master before installing. 

yep

As mentioned bench bleed the master to start.

I use one of two methods for the rest;

Back bleed the system using the caliper bleed screws

or

Run a hose from the caliper into a container filled with brake fluid and pump the pedal...........this works well for one person.

Also note I fill the calipers on the bench as well.

Reverse bleed if you can.  Stick some Teflon tape on the bleeder screws so the threads seal to the caliper, and push fluid in from the bleeders.  Air will be forced up, the way it naturally wants to go, and out into the reservoir.  This also bleeds the master cylinder.

Easiest to do this before you put any fluid in   Sometimes this is the only way to get all air out.

Another tip...gently tap on calipers and master periodically to loosen sticky air bubbles. 

Tom1200 said:

As mentioned bench bleed the master to start.

I use one of two methods for the rest;

Back bleed the system using the caliper bleed screws

or

Run a hose from the caliper into a container filled with brake fluid and pump the pedal...........this works well for one person.

Also note I fill the calipers on the bench as well.

 

I have been known to run lines back to the master on a new system with all fresh fluid.   I also use clear line so when I am sitting in the drivers seat I can see the air bubbles in the line comming out of the system and when they stop. 

I will admit it. I do not bench bleed master cylinders and I haven't for decades.

First point, The moment you disconnect your bench bleeding lines they are no longer "bled". Second point, I have never not spilled brake fluid all over the car I am installing a "bench bled" master into.

They are such simple devices. A bit of pressure on the master side or a bit of vacuum on the brake side usually does the trick. 

I haven't done the fancy reverse/vacuum bleeds, but I did break down and get a Motive power bleeder. Got an adapter from eBay to fit the Miata master res. Its way easier to dump some fluid into it and pump it up than to get a second person, especially if its a new system and might take a while. Wife thinks its the best tool purchase I've made!

amg_rx7 (Forum Supporter) said:

1990 NA Miata non ABS

I just installed a new master cylinder, calipers, and ss lines. Hard lines were blown out. Entire system is effectively dry. 

I filled the reservoir and attached a Motive pressurizer thing at the master and used a handheld vacuum pump for good measure to pull fluid to each caliper. 
The brake pedal still feels soft. Figured I'd ask for tips and input on whether I'm on the right track as I've never dealt with a totally dry system before. 

Put some additional time into this last night. And bled again using the Motive power bleeder and pumping the pedal to work the master. Looks like my process worked. 
The pedal is feeling normal. 

Next step will be to do a 2 person bleed for good measure 

Trent said:

I will admit it. I do not bench bleed master cylinders and I haven't for decades.

First point, The moment you disconnect your bench bleeding lines they are no longer "bled". Second point, I have never not spilled brake fluid all over the car I am installing a "bench bled" master into.

They are such simple devices. A bit of pressure on the master side or a bit of vacuum on the brake side usually does the trick. 

 

 

Yes they are simple as long as they are perfectly level. I hate bench bleeding too and feel it should be useless for the same reasons.

Still, I struggle to bleed brakes nearly every time I try it.

Fill a (new) oiler with brake fluid. Attach a clear tube from the oiler to one of the bleeders. Open that bleeder and pump fluid into the system until no more bubbles come out at the reservoir.

Andy Hollis said:

Another tip...gently tap on calipers and master periodically to loosen sticky air bubbles. 

 Calipers with integrated parking brakes have lots of places inside for air to hide. A lot of times this is the only way.

Also struggling here with a brake bleed.  My master has three ports coming out of it.  Two up front and high on the side of the master and one on the bottom.  The bottom one goes to the LF the front two got to the prop valve one for front brake one for the rears.