Bleeding brakes, sucking air from Master cylinder?
- Thread starter optimusprime
- Start date
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optimusprime
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Problem finally resolved!
Thanks for all the great advice from everyone. The fix ended up being very simple. I ended up buying a Mityvac just for ease of operation for when I have to do it again. The problem was actually in the threads of the bleeders themselves. When I was bleeding the fronts, the cracking of the screws was causing air to be sucked in through the threads. Probably wouldn’t have been an issue had I done the standard bleed procedure with opening and closing the valence each time the pedal was depressed but with the hose and constant pump method air was being sucked in through the threads on both sides. All I did was smear silicone grease around the fitting threads before I bled it, which kept any air from being sucked in through the threads. I will probably replace the valves as they are starting to look pretty rusty. The Mityvac made it much easier. Finally got all the air out of the lines and just finished bedding my brakes and rotors. Again, thank you all for your input and advice!
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Thanks for all the great advice from everyone. The fix ended up being very simple. I ended up buying a Mityvac just for ease of operation for when I have to do it again. The problem was actually in the threads of the bleeders themselves. When I was bleeding the fronts, the cracking of the screws was causing air to be sucked in through the threads. Probably wouldn’t have been an issue had I done the standard bleed procedure with opening and closing the valence each time the pedal was depressed but with the hose and constant pump method air was being sucked in through the threads on both sides. All I did was smear silicone grease around the fitting threads before I bled it, which kept any air from being sucked in through the threads. I will probably replace the valves as they are starting to look pretty rusty. The Mityvac made it much easier. Finally got all the air out of the lines and just finished bedding my brakes and rotors. Again, thank you all for your input and advice!
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George B
¯\_(ツ)_/¯
Glad it was simple. I usually put anti-seize on the bleeders once I have them loose but never use the method you were for bleeding. If I have to bleed brakes again I am just gonna order the motive bleeder.
Jason in DLH
Cheeseburger and Fries
I’ve heard of that happening, but didn’t even think of it here. Glad it wasn’t a bigger issue!
ThomasKelly1952
TYF Newbie
Yes Did that had to bring it into a mechanic I couldn't fix it nor could 2 mechanic (friends)
I also use the Motive pressure bleeder, won’t use anything else. So much better and easier than a vacuum bleeder. Perfect for a full system flush which should be part of everyone’s maintenance schedule. Glad you got it figured out. Sounds like you dodged a bullet on that MC by pressing the pedal to the floor. Next time add a piece of 2 x 4 on the floorboard so it can’t happen.
Joseph Garcia
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Thank you for posting your solution to your issue. Our collective knowledge base has been increased.
I did the same but with no beer and found that when my wife released the pedal, the air was suck in from the valve thread. So I went back to two-people way.
I'm just sharing my experience. You probably didn't loose the valve too much. It's worth to notice it.
You’re supposed to have the person hold the pedal steady, then you tighten the bleeder, then they release the pedal. The only time the bleeder is loose is while the pedal is going down.
Yes, you are right about it.
I will use gravity way next time. No pedal pump, have a beer and just watch the fluid level.
