Brake line routing vs. trapped air

[woody80z28]

Are there any no-no's with brake line bends & routing that are likely to trap air and make bleeding difficult?

I have been chasing a spongy pedal for quite some time. Tried different master cylinders & calipers and done what seems like a lifetime's worth of bleeding brake fluid. I've checked the master cylinders by plugging the outlet ports and it hydraulically locks. But when in the car, the pedal is spongy and never hits a wall. I can not get any more air out of the lines...tried pressure, vacuum, gravity and pump & crack. Even took it to a shop a while back to see if they had any tricks with no change.

Can the problem be in my line routing? I do have a couple loops between the master and front calipers because of my line lock routing. At no point is the line higher than the master cylinder, but I could potentially see it causing a place for air to get caught.

At this point I'm grasping at straws.

[Skip Fix]

Woody a loop could trap air but generally it will flow out esp if tapping there while bleeding, but I'd sure look at the MC might be bad. BTDT. Put some plugs in the out ports on the MC and it should hydraulic lock after maybe 1/8-1/4" travel of the piston. If not it is bad.

Tobin clued me into that test. I also used it after bench bleeding my last one to be sure as that MC took forever to get all the bubbles out.I would think I was done then some more would come out.

[Skip Fix]

Also it took forever to get the air out of the line lok. Had to keep tapping it. Flipped the solenoid while bleeding also.

[woody80z28]

Yup, checked the masters and they lock hydraulically. That was my first thought too. I plan on removing the line lock temporarily to see if that helps the bleeding process. Tobin got me on track there, too. He's been a big help. I was bleeding them with plugged ports and could not get the air out...so I bled with steel lines bent back in to the reservoir until I got no more bubbles and checked with the ports blocked and they were good.

I called Wilwood and they are sure there must be air in the system. They said my components match up fine and I should have a high, hard pedal. The suggested a brake pressure gauge in the bleeder port to see what I get. And if I pump the brakes and the pressure increases there is air in the system. My new gauge should be here tomorrow from Summit.

[Skip Fix]

Check that Line lok it held air in mine forever also. Could have bad O rings and be sucking air in .Might T around it as a trial.