TFeld78

Question 1

Will worn brake rotors cause the brake pedal to feel soft?
(Assuming there is no air in the system). Sometimes I
have to press pretty hard to get the car to stop. The
pedal doesn't seem soft like air in the line, just not effective.
Also, sometimes, the brakes grab or shudder as if they were
wet. BTW, I have organic pads (at least they don't squeak!!).

Question 2

If the rear rotors are original, and the rivets have to be drilled
out, is there a technique to this? What size drill bit? Any
suggestions?

This is on a 1978.
Thanks!!!

GTR1999

Sounds like the caliper(s) might be sticking or leaking if they're pulling to one side. If the rotors were warped you would get a pulse feeling, low pedal could be air in the system or bad M/C.
The rivets are a PITA to remove but can be done. Center punch them,center drill, then step up to a 1/4" and finally 5/16 to get past the head of the rivet. Then use a chisel to get the head out and a punch to get the body out.
Good luck,
Gary

73Ken73

If you can't lock up the brakes then you really shouldn't drive the car. It is probably some air in the system.

TFeld78

Any suggestions on checking for sticking calipers?
I assume on the front, I can put the car up on
jack stands, and try to turn the wheels while an
assistant presses on the brake.

But what about the rear? Will this work as well with
the car in neutral?

Thanks.

lyonsh

Q1: Worn rotors won't make the pedal feel soft. But worn out pads will make it harder to stop (as will worn rotors if they're REALLY worn a lot), and warped rotors will sometimes feel like they're grabbing.

Q2: Center punch the rivet - in the exact center! - then start with a small drill and work your way up. I don't remember the exact size drill, but you should be able to tell when then rivet stud is about gone. If the head doesn't pop off when you've got the center drilled out, cut off the head with a cold chisel. Then if there's a little bit of the rivet center still in the hole, you can usually punch it out.

For stuck calipers, yes you can have someone hold the brakes and check the rears as in the front. If you've got the rear wheels off the ground, it's not that hard to turn them -- all you have to overcome is the resistance in the differential.

Another trick: if you suspect stuck calipers, you just might have a piston that's cocked in its bore. A quick way to check: go to an empty parking lot, get up to about 30 mph and make a fairly hard stop. Then put the car in reverse and back up. If you hear a substantial "pop" that's the piston uncocking itself, and it's time for a little caliper work.

Good luck :cheers:

Barry's70LT1

Q1 Also, the flex lines, (one going to each wheel), can collapse on the inside and look perfect on the outside. They are a two layer rubber line. The inner layer
can crack and split which causes the restriction.
This causes a severe restriction to the flow of brake fluid to the wheel.
This will result in all kinds of weird brake problems.

boredsoIstrokedit

can anyone post a picture of the rear rivets or describe them, i dont want to start drilling and punching until i am sure what i have got.

ZD75blue

the rivits are these tiny little things that are around center hub. i havent pulled mine to check em out, but i think there was a pic on here a while back...