brakes drag sometimes.

[rcsavage]

was driving today and on two occasions, noticed that the pedal stayed low and was dragging the brakes. one time it did this, was after i had let off the brake, was engine braking, and when i went back to the brake, the pedal was low.

Dad said that its the "vacuum booser" and that we wont replace it because it costs "600 dollars". i cant find that part anywhere. he just wants to drill a hole through the pedal and attach a spring to keep the pedal up. to me, this sounds like a bad idea. he insists that it will be fine and that he did it to his old sho.

can someone help me? why would my pedal stay low like that. i assume that since it dropped when i was at a high rpm, it has to do with the vacuum going to the brake booster. (am i even on the right track?) thanks in advance guys.

 

[SASHO91]

The spring inside the MC does loose its compression after time. I noticed this on the 91' a few months back.. Mounted a spring to the pedal(about halfway up the arm) and hooked it to the metal cover... works fine.

But I would just double check the rear calipers just incase.

 

[wood_e]

Check the vacuum line to the booster. The brake booster costs $45 at rockauto.com....

 

[frosho]

could be the rear hoses too

 

[Daedalus]

I'm having the exact same problem in my '91.

Is the return spring in the vacuum booster or the master cyl? My '74 Dart has the springs in the master cyl, so replacing the vacuum booster wouldn't help. (The vacuum booster is only a diaphragm that helps pull the pedal down using manifold pressure)

If I understand the system correctly, swollen rear brake hoses, while causing the brakes to drag, would allow the brake pedal to come all the way back up.

 

[dantheman68]

using a spring is a perfectly acceptable way to "shadytree" fix it... and i bet a few mechanics would reccomend it before the $600 alternative... there is a spring that has the pedal return to the normal height anyway, youre just replaceing it with one thats easier to change when it wears out

 

[wood_e]

Funny thing is the $600 alternative is bull, it's a $50 alternative

 

[doclees]

When my rear flex hoses gave out I didn't get any change in peddle feel. But the fire was a real good clue that the caliper had locked up.

 

[Daedalus]

If I am reading this thread correctly, the master cylinder is the part with the return spring? Or is it the vacuum booster?

Will any of the master cylinder rebuilt kits from RockAuto work in a SHO? They are listed under SHO, but only the $26 Dorman part says it will work with ABS.

 

[projectSHO89]

The return spring is in the booster, not the MC.

Steve