Vaccum Brake pedal sits low

[rbarragan]

Hey guys I have recently removed my powermaster setup to a vaccum setup. I installed a new master cylinder and vaccum canister. Bled the system and the car stops but the brake pedal sits very low. It seems like when I step on the brake pedal im all the way to the floor. There are no leaks in my system and I also bench bled the master cylinder. I was thinking the rod that attaches to the break pedal is not long enough and does not allow the brake pedal to come up higher. Anyone else have this issue? Can I buy a longer rod to attatch to the brake pedal?

 

[SuperSix]

Did you replace the brake pedal assembly too? If not, you need to. The PM and vacuum brake pedal assy are different - fulcrum point is in a different spot.

 

[rbarragan]

Yes I replaced the brake pedal with one out of a vaccum brake regal from the junk yard.

 

[rbarragan]

Anyone have any other suggestions?

 

[m1tankr]

Anyone have any other suggestions?

What are all the parts you used. It should come to the same height the old pedal did.

 

[rbarragan]

I used all parts from a donor car in the junkyard. Got the pedal canister and rod from the car. The master cylinder is brand new.

 

[Vince13]

Make sure you depress the plunger on the brake proportioning valve when you bleed the brakes. There is a good write up here http://www.gnttype.org/techarea/brakes/linelock.html
Check that your rear shoes are adjusted up so there is just a very slight amount of drag and your emergency brake cable is tightened up so it only takes 3 -4 clicks to fully engage.

 

[turbo96max]

i had and continue to have the same issue. got everything from a donor yard regal, and when i slam on the brakes, the pedal bottoms out but the car still slightly rolls. i may try rebleeding with the valve deal mentioned here and see what happens. a few auto parts check valves have blown too, im not too convinced on this swap yet.

 

[m1tankr]

i had and continue to have the same issue. got everything from a donor yard regal, and when i slam on the brakes, the pedal bottoms out but the car still slightly rolls. i may try rebleeding with the valve deal mentioned here and see what happens. a few auto parts check valves have blown too, im not too convinced on this swap yet.

You might have a bad or leaking booster. I didn't notice the part where the parts were used. I'm doing the swap right now (this will the 3rd one I've done on TR's. Always had good results. This time I just ordered a new unit (master cylinder/booster combo from Rock Auto) for $120. I figured the used parts are 25+ yrs old. What did you do for the vacuum line block?

 

[turbo96max]

You might have a bad or leaking booster. I didn't notice the part where the parts were used. I'm doing the swap right now (this will the 3rd one I've done on TR's. Always had good results. This time I just ordered a new unit (master cylinder/booster combo from Rock Auto) for $120. I figured the used parts are 25+ yrs old. What did you do for the vacuum line block?

master cylinder was new, actually ran through a few gm models looking for the thicker diameter rod to see if it helped. the booster looked good , didnt look that bad in shape , but i will probably just go out and get a new one to test. i am using the longer unit, dual diaphram if i remember correctly, not the short more flat wider unit. which one have you been using? my vac block ontop of the throttle body is the billet version with the vac brake port.