Master Cylinder - bench vs. in-car bleed
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Ive got air in places it shouldn't be :blink:. Woohoo! So, is bench bleeding the master cylinder than better cracking the lines leading to the ABS block, as per the GM service manual bleeding procedure, or just less messy? Won't they acomplish the same thing?
Thanks
BobP
Thanks
BobP
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Honostly I think it would be just too much hassle to bench bleed it unless it's already unbolted. If I've ever had air in the system I've always just bled them normaly until there wasn't anymore air in the system. There shouldn't be air in there period, i would check to see if there's anything leaking first.
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Thanks for the input. Actually, I let the master cylinder drain down too low while dropping the axle so I think I let some air into it
. Anyway, I can't get a hard pedal after pushing a quart of fluid through. I got a response on another thread that it's hard to bleed fully in the car since it sets at an angle. So, I'll pull it then work on flushing the ABS as well.
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Thanks for the input. Actually, I let the master cylinder drain down too low while dropping the axle so I think I let some air into it
. Anyway, I can't get a hard pedal after pushing a quart of fluid through. I got a response on another thread that it's hard to bleed fully in the car since it sets at an angle. So, I'll pull it then work on flushing the ABS as well.
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
Did you have too bench bleed your master?
Thanks for any help
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^^ you just need hoses or brake lines going from the out of the master and reciruclating the fluid back into the resivoirs. Make sure the ends of the lines sits in brake fluid. Bolt it in the vice and use a screw driver to push the piston in. and backand forth till there is no more air bubble coming out. After you bolt it back on the car have a buddy push the pedal down and crack the lines at the master.
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Google "Dorman 13911" for an inexpensive kit. I don't know if any sponsors carry it - I got mine through a local national chain. Have them confirm that the kit includes kit one M12 x 1.0 and one M11 x 1.5 fitting. Those are the ones you need. It's an easy job.
If you do have air in the ABS, then your options are to take it to a shop that can cycle the ABS solenoids, or try it on your own. Search for ABS Bleed here and you likely find the procedure. Better yet, check your shop manual if you have one. It involves putting the car on stands, starting a few times per wheel and putting it in gear to cycle the solenoids while bleeding - you'll need a Mighty Vac or similar unit to do it alone.
Good luck.
BobP
If you do have air in the ABS, then your options are to take it to a shop that can cycle the ABS solenoids, or try it on your own. Search for ABS Bleed here and you likely find the procedure. Better yet, check your shop manual if you have one. It involves putting the car on stands, starting a few times per wheel and putting it in gear to cycle the solenoids while bleeding - you'll need a Mighty Vac or similar unit to do it alone.
Good luck.
BobP