Brake Bleeding question on a 68
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Brake Bleeding question on a 68
I installed a new master cylinder and entire system is dry, no fluid in lines or calipers.
I am gravity bleeding starting with passenger rear caliper.
My questions are:
Should the master cylinder cover be on or off while gravity bleeding?
Sine the rear calipers have two (2) bleeder screws per caliper, do you open both screws at the same time on the caliper or just one at a time.
Need help please as I am trying to get this done today.
Thank you in advance,
I am gravity bleeding starting with passenger rear caliper.
My questions are:
Should the master cylinder cover be on or off while gravity bleeding?
Sine the rear calipers have two (2) bleeder screws per caliper, do you open both screws at the same time on the caliper or just one at a time.
Need help please as I am trying to get this done today.
Thank you in advance,
Instructor
Joined: Jul 2002
Posts: 245
Likes: 0
From: Raleigh NC
Re: Brake Bleeding question on a 68 (ksbunting)
Hmm, I always thought if the entire system was dry that the master cylinder should be bench bled to work the bubbles out of that before bleeding the rest of the system. The MC should have come with a kit to do so.
I imagine since you're gravity bleeding you can open up both screws for the rears, but I think if you were using the old pump and hold method you'd do the outers then the inners. But I could be wrong on that too.
Standard DOT-3 brake fluid sucks up moisture like crazy, I'd rather have the cover at least sitting on top of the MC to minimize the amount of moisture that gets into the lines. Synthetic dot-5 brake fulids don't have this problem as much, plus it wouldn't mess anything up were you to spill it on some other part of the car.
I imagine since you're gravity bleeding you can open up both screws for the rears, but I think if you were using the old pump and hold method you'd do the outers then the inners. But I could be wrong on that too.
Standard DOT-3 brake fluid sucks up moisture like crazy, I'd rather have the cover at least sitting on top of the MC to minimize the amount of moisture that gets into the lines. Synthetic dot-5 brake fulids don't have this problem as much, plus it wouldn't mess anything up were you to spill it on some other part of the car.
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Re: Brake Bleeding question on a 68 (Enkil)
Enkil,
Thanks for the rapid reply.
I did bench bleed the master before installing into the car yeaterday.
I am using Ford Heavy duty brake fluid as it came highly recommended for Corvette brakes by several on this forum.
Just can't seem to get any fluid at the wheels and I let it gravity bleed for at least an hour.
Thanks for the tip on keeping the master cylinder cover on.
I agree about the air and possible contamination. Just didn't know if it would disrupt the flow in any way by causing an air pocket or whatever.
I am confused and frustrated as hell at this point.
Thanks for the rapid reply.
I did bench bleed the master before installing into the car yeaterday.
I am using Ford Heavy duty brake fluid as it came highly recommended for Corvette brakes by several on this forum.
Just can't seem to get any fluid at the wheels and I let it gravity bleed for at least an hour.
Thanks for the tip on keeping the master cylinder cover on.
I agree about the air and possible contamination. Just didn't know if it would disrupt the flow in any way by causing an air pocket or whatever.
I am confused and frustrated as hell at this point.
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Re: Brake Bleeding question on a 68 (wombvette)
Have tried everything, suction, pumping, and still no fluid movement.
Does anyone know what can go wrong with a master cylinder rebuild since there are so few parts involved and they only go in one way?
Have tried at front and rear calipers and no fluid, even using suction.
Master cylinder moved fluid OK when on the bench while bleeding air.
Does anyone know what can go wrong with a master cylinder rebuild since there are so few parts involved and they only go in one way?
Have tried at front and rear calipers and no fluid, even using suction.
Master cylinder moved fluid OK when on the bench while bleeding air.
Instructor
Joined: Jun 2003
Posts: 156
Likes: 12
From: Arkansas
Re: Brake Bleeding question on a 68 (ksbunting)
couple of weeks ago,i did all calipers. i also had a dry system. tried and tried to pump and hold, suction type bleeders. never any satisfaction. i talked to a local mechanic. he told me best for a corvette is to pressure bleed. i used his pump and WOW! now i have a great brake. instuctions say to bleed the inner bleeders first. hope this helps
Advanced
Joined: Jun 2003
Posts: 59
Likes: 0
From: Smithtown NY
Re: Brake Bleeding question on a 68 (olelucky)
The $40 investment in a hand vacuum pump bleeder is well worth it. You'll have the brakes done in no time. Start with the furthest point from the MC (RR outer) and work your away around. When you're done, the hand pump does double-duty as you can use it to trouble shoot problems with all of the vacuum operated everything on the car.
