Brake issues
Thread Starter
2nd Gear
Joined: Jul 2011
Posts: 2
Likes: 0
From: Los Angeles CA
Brake issues
I swear I searched, before hand.
I picked up my grandpas old 78 L48 a couple weeks ago and have been struggling with brake problems ever since. First things that got replaced was the right front caliper where the piston seals had gone. I thought that would fix it but I'm running into an odd problem. At higher speeds (normal street driving 45ish) the pedal is nice and firm. Slowing down for a stop light the pedal is initially firm but then basically goes to the floor board. Needless to say the car is parked while I try to figure this out. Now I'm not losing any brake fluid anywhere and I was told the Master Cylinder is in working order. I think it has to do with the vacuum assist, but I wanted to ask if anyone else has experienced this or if there's another item I should be looking at.
I picked up my grandpas old 78 L48 a couple weeks ago and have been struggling with brake problems ever since. First things that got replaced was the right front caliper where the piston seals had gone. I thought that would fix it but I'm running into an odd problem. At higher speeds (normal street driving 45ish) the pedal is nice and firm. Slowing down for a stop light the pedal is initially firm but then basically goes to the floor board. Needless to say the car is parked while I try to figure this out. Now I'm not losing any brake fluid anywhere and I was told the Master Cylinder is in working order. I think it has to do with the vacuum assist, but I wanted to ask if anyone else has experienced this or if there's another item I should be looking at.
Race Director
Joined: May 2006
Posts: 18,604
Likes: 2,540
Did you check every caliper for fluid seeping past the seals? Did you bleed the whole system starting with the right rear, left rear, right front, left front? Too much rotor runout causes air to be sucked in past the seals.
Thread Starter
2nd Gear
Joined: Jul 2011
Posts: 2
Likes: 0
From: Los Angeles CA
Yeah, when I had the right front done I had the rest of the calipers checked. I don't know if they bled them in that order though. That fix was kind of an emergency stop as I was in the midst of driving the car back down to LA from where it had been stored in Idaho.
It doesn't feel like it's air in the lines system as the pedal is rock solid and not spongy at all until I start to slow to a stop.
It doesn't feel like it's air in the lines system as the pedal is rock solid and not spongy at all until I start to slow to a stop.
