Hey guys,

I have been scratching my head and have not been able to come to a reasoning for the following problem I am having bleeding my brakes. (Sorry about the length.)

Preceding my LS1 Brake upgrade, I installed the LS1 Master cylinder. I bleed all the calipers starting at the rear passanger, rear driver, front passenger, then the front drivers side. This is where my head scratching began. All the calipers bleed fine and bubbles stopped coming out of the hose in the catch can after a few pumps of the brakes. That was until I bleed the front drivers side. After pumping it thru 5 times I was still getting bubbles coming out of the hose. Thinking maybe the caliper piston was full of air, i filled the res. and pumped thru the the entire res., making sure not to empty it. I closed the speed bleeders and took the car for a test drive.

I set the prop valve to full pressure to start. Got up to about 15 MPH hit the brakes and the rears locked. The pedal felt low, but I was just testing so it did not register. I backed off the prop valve to the point that the rears were wanting to lock up before a complete stop. Then I got up to about 35 and stood on the brakes. The car stopped fine but neither the front or rears locked up. I was happy that the car stopped in a straight line, but unhappy that the fronts did not lockup. Not a big deal, knowing that the LS1 Setup would clear that up. While driving home was when I noticed the pedal was lower that before the M/C swap. I thought that maybe there was some air in the system, so I blead all the brakes again. All were fine until I the front drivers side. I blead that damn caliper and put over 32 oz of fluid thur it, and I still get bubbles when I pump it. There are no visable leaks at all in the front.

Does anyone have any ideas as to what can be causing this? I will be upgrading to the LS1 setup soon, but I want to resolve this before if possible.

Thanks in advance,

 

Depending on how you bleed the brakes it in possible to saturate the fluid with tiny air bubbles which are almost impossible to get out. I have seen that a lot, especially with one man bleeders you tend to pump the pedal to fast and instead of pushing the air out it breaks up the air into tiny bubbles and saturates the system. Either let it sit for a day or so without touching the pedal or gravity bleed the system, meaning take out the speed bleeders and let the fluid run out on its own just keep the M/C full. I have had to use 3 or 4 32oz bottles of brake fluid before . It might take quite a while so be patient and take your time you should be fine.

 

Well I am glad I am not the only one that has had the problem. I was begining to wonder. I have allowed the car to sit for a few days between bleeding. I even tried to pump slow and fast. The bubles are not small they are regular size like if you were bleeding a open system. I will gravity bleed them tonite. It hase been raining here, so I will try and take it out for test drive later today. Thanks,