Hey guys, heres what I've done so far. C6 z51 calipers and rotors up front, 2002 Camaro rear axle swap with discs. At this point I'm pretty confident my lines are all empty. Still have the OEM master cylinder mounted at this time. I planned to swap it for the 2002 MC as the OEM is garbage at this point. Heres my question. Would it be best to fill the lines using the OEM MC with fresh fluid by opening the bleeder and letting gravity do the work. Then bench bleed the new MC and power bleeding all corners after its installes? Or should I skip the bench bleed and line filling, just power bleed the whole system at one time? I've never delt with an empty line before so not sure what to expect.

 

It's not really going to matter. When you swap the MC you are going to have air trapped at the front of the circuit that has to make its way to the bleeder screw anyway. My personal opinion is, I like to see them gravity bled more than anything. Lets you know you have free flow in each circuit to each caliper. This is a hobby, not an on the clock job. I used a vacuum bleeder to fill mine last time, and in the end gravity bleeding got the last little bit of air out.

If you are using a power bleeder that will push brake fluid... Just swap it all over and shove it in.

 

Thank ya sir.

 

Compare to:

YOU doing the … w … wo.... wo... wor… [baaaaaarrrrrrfffffffffffff] sorry, I REALLY tried, but, just can't say that word. My mom used to wash my mouth out with soap when I said foul 4-letter words like that. Early-learned patterns are hard to overcome.

Ummmmmmm……… which one looks better to you?

That said, in these cars, GOTTA bench bleed the MC. PERIOD. The lines aren't at the highest point in the MC. Meaning, no matter how much you bleed the system after the MC is installed, it will NEVER get all the air out of the MC. You can bleed it EVERY DAY, and even TWICE every Sunday, and it will NEVER EVER EVER EVER EVER get all the air out of the MC. Gravity, pressure, WHATEVER; doesn't matter. The air is TRAPPED up there. GOTTA "bench bleed" it, otherwise your future is HOPELESS.

 

Sorry if I gave the wrong impression... this is absolutely a true statement.

Still, even if you bench bleed and fill the lines... when the OP would swap the MCs, there would be air trapped in the circuit which is what I was getting at. There is no extra value in filling the system then swapping.

 

Heres what's in my mind. If I bench bleed the MC then attach the lines. The air is going to rush back into the MC anyway. I'm not fighting the idea of bench bleeding, just trying to get it right the first time.

 

Not true. It will not rush back into the MC.

I bought a kit for bench bleeding. The last time I installed a MC, I bench bled mine with the tubes to return fluid to the reservoir. Then, I swapped out for plugs that came in my kit and mad sure the plunger had a good hard stop with the outlets plugged. Installed it in the car with the plugs in. Then removed them one at a time and installed the lines. BTW, don't tighten the MC to the brake booster before installing the lines. Makes getting the threads lined up a bit easier if you can move the MC around to get them to match up. The brake lines can kink pretty easily.
Then I went to each corner (Pass Rear, Driver Rear, Pass front, Driver Front) and just gravity bled them until I saw air appear (my lines were already filled) and then waited until I saw it stop having air bubbles. Closed it all up. The following evening just to be sure, I had a friend help with the two man method, just to confirm.

I have used a vacuum bleeder and while it will help move the fluid quickly, couldn't seem to get the last bit of air out using it.