Topic: Not quite Brake Hell II, but....
in Forum: C3 Engines, Driveline and Handling

Ok, so I rebuilt all 4 calipers, installing VB&P's O ring conversation kit, 4 new rotors (the old ones appeared to be original), and a new mater cylinder from Corvette Central.
Now the pedal goes almost all the way to the floor, and barely holds the car at idle in forward or reverse. The brake warning lamp is functional, but does not illuminate when I press on the pedal, indicating to me that the proportional valve is not an issue. I have not taken it out on the street, as I feel decent brakes are a good thing!
I have bled those puppies by gravity first, then via the pedal approach until NO bubbles appeared, then I went around and tapped on each caliper with a rubber malet to dislodge any trapped bubbles. Then I bled them again and saw little or no bubbles. No leaks apparent anywhere.
Other than the power poster, any ideas? I thought when the booster goes bad, pedal effort increases, which is not I case I find. I will checking the length on the adjustable rod that transmitts the action from the booster to the M/C vs the spec.
Any and all suggestions ( as they relate to my problem) will be greatly appreaciated.
Thanks
NJ BB Ken

1972 T Top 454; "Boomer" Latest "upgrades": 1 1/8" front Stabilizer bar. Rebuilt SS calipers with O-ring pistons. Under car Chambered exhaust. Fiberglass rear spring (360lbs/in). Bilstein Rear Shocks. 3/4" Rear Stabilizer Bar. Tow hitch. Performer manifold with 600 cfm Holley. Comp Cam 262 .499 lift. L-88 Hood in process

have someone push the pedal while you check and see if they are swelling.
Reid '72 T-top


I had installed SS braided hoses when I installed the SS sleeved calipers when I first got the car ('88).
This is most frustrating, as I essentially did the same things to my '67 roadster, and had pretty good brakes as a result!
As the Stones once said, "Let it Bleed!"
Cheers
NJ BB Ken

1972 T Top 454; "Boomer" Latest "upgrades": 1 1/8" front Stabilizer bar. Rebuilt SS calipers with O-ring pistons. Under car Chambered exhaust. Fiberglass rear spring (360lbs/in). Bilstein Rear Shocks. 3/4" Rear Stabilizer Bar. Tow hitch. Performer manifold with 600 cfm Holley. Comp Cam 262 .499 lift. L-88 Hood in process

i prefer actively bleeding the brakes..
i used a pair of those speed bleeders recently and they rock.. the easiest ive ever done..
you might try to screw those little plastic fitting from a master cylinder bleed kit into it.. bleed the master cyl.. then leave it over night..
rebleed it in the morning and see if there is any air in the MC. if not the MC is ok..
use brass fittings and block off all the brakes but one. bleed it.. tap on it with a hammer.. let it set for a few hours.. rebleed.. any air..
repeat with each wheel until you find the leak.
I'm having a similar problem. I've gone through all the same steps, but still have a soft pedal (not as bad as yours though). I'm waiting to see how things work out for you before tackling my problems. My brakes still stop adequately, but not as well as I think they should.
Keep us posted!!
Thanks - Al

I have completed the replacement of the power brake booster, it was not as bad as I thought it was going to be, but then I removed the driver seat and the steering wheel to allow the easiest access under the dash. ( I strongly reccomend this to anyone attempting to replace their booster!) Even with the easier access my lower back is barking a bit today!
The brakes feel better, although I am in the process of installing the Reflectix insulation in the driver side, and have not sat in the seat and depressed the barkes with the engine on yet. As with most projects on a 32 year old car, You start out to replace "A", and you find you also need to address "B", "C", & "D"!!!
So, when I removed the driver seat, I discovered the carpeting was shot, so I ordered up a set from Wilcox Corvette parts. Having heard the good opinions on the value of installing the Reflectix, I went out and got roll of the insulation from Lowes. I should have the Driver side finished by the weekend, so I'll post my brake status then. Before I give it the once around the block test, I intend to give the brakes one last Vac. bleed with my Mini-Vac pump.
I finally got my Collectors Insurance, so the Historic Plate application goes in today!!

I hope to actually do some damage out on the street with the car before the glaciers return this winter.

NJ BB Ken
1972 T Top 454; "Boomer" Latest "upgrades": 1 1/8" front Stabilizer bar. Rebuilt SS calipers with O-ring pistons. Under car Chambered exhaust. Fiberglass rear spring (360lbs/in). Bilstein Rear Shocks. 3/4" Rear Stabilizer Bar. Tow hitch. Performer manifold with 600 cfm Holley. Comp Cam 262 .499 lift. L-88 Hood in process