Brake pedal does not return to full up position?

[tcs69rt]

This car does have a large cam! I have searched and read this pedal problem with alot of you. My 69 RT has new master cylinder, rebuilt front disc calipers and all new lines. I bled the system and had great pressure until I backed t of the driveway last night. Pulling the car into drive the brakes took about 2 seconds and then released allowing the car to roll forward. The pedal will sometimes build up enough pressure to return and the brake lights do not stay on but after a ride last night...it is not returning at all and the brake lights are stuck on because of the low pedal height. So, I pulled the battery terminal and will get to it tonight.

Once again it has a big cam, 25 miles on it since replacing all the new parts. No leaks with the system. Pedal is not rock hard so I think that tells me the new booster is working. Pedal will go down alittle after starting engine. I did pull the master cylinder cover, pressed the pedal with engine off and did not see any bubbles? Should I start there and adjust the master cylinder pushrod, then bleed the brakes again? Suggestions?

Thanks! TC

[Rolling_Thunder]

I would double check the master cylinder pushrod length especially if you installed a new booster.  I would then bleed it just to be sure.

[tcs69rt]

I'll do that this afternoon, thanks!  TC