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View Full Version : Stock Master Cyl and Wilwood 4-piston calipers - no movement



Tweaked Zed
05-11-2010, 07:54 PM
Just bled all my wilwood calipers tonight, and figured I'd just use the master cylinder that was in the car (69 camaro) with the stock power disc/drum setup. I changed out the prop valve to a disc/disc, and away I went. Well, after a long bleed process, the pedal still goes to the floor, and the pads hardly move at all. And I mean just a tiny bit that you can barely see, so they don't even touch the rotors. Do these Dynalite 4-piston calipers need that much more fluid? Can I get a stock-looking master that will move enough fluid, if that's the problem? Anybody here run 4-wheel wilwoods with a stock master?

Thankyou for any and all help.

Bryce

Vegas69
05-11-2010, 08:05 PM
Sometimes when you reuse an old master cylinder you cut the piston seals. The master piston travels into uncharted territory and the orings get compromised. Did you run the master dry bleeding? If you did, then it's time to bench bleed the master cylinder.

Tweaked Zed
05-11-2010, 08:26 PM
Definately did not run it dry. I just tried using the bottom hole on the brake lever for a longer actuation stroke, but that doesn't work either. I find it odd that the pads hardly even move. The brakes worked fine with the stock disc/drum setup.

scott0
05-11-2010, 08:48 PM
are you getting a good amount of fluid out of the bleeders while bleeding?

speED
05-12-2010, 05:09 AM
On a 67 Camaro, I currently have stock type calipers in front with 4 piston wilwood in rear. I used a stock master from a 66 Vette (disc-disc) with an adjustable proportioning valve in the rear line only. Brakes work good, I eventually will change front to C5 set-up.

Tweaked Zed
05-12-2010, 03:55 PM
Thanks Vegas. The master is toast....

Vegas69
05-12-2010, 04:05 PM
Glad you figured it out. It happens quite often.