[Y-Blockhead]

Purdy's Brake adjustment procedure has always worked for me. And yes, the 15° lever position must be correct before you start. Add pills or replace parts as needed to reach 15°.

No, Purdy does not use the "Brake Board".


Purdy’s Brake adjustment

Here is what works for me, even if there is wear in the system. Disconnect all of the service brake rods at the clevis end. Adjust the brake pedal rod so that the brake switch plunger is 1/16 inch from the inside back of the center cross member with the brake pedal at the top of its travel. This is where the pedal rod plunger contacts the brake light switch on the 30-31 models. In extreme cases, to give more threads at the clevises it may be necessary to adjust the pedal rod all the way back to the center crossmember without the 1/16 gap. Because there will nearly always be some wear in rear wheel bearings and axle housing bearing races, I first adjust the rear brakes. With any wear, rear brake adjustments made with the rear wheels off the ground will be TOO tight with the wheels on the ground. With the tires properly inflated for easy roll, I adjust the rear brakes with the tires on the shop floor. You only want very slight drag if any or the brakes will quickly overheat. Unless something is too tight, wheel bearings, brakes or the tires are low, a man should be able to slightly push the car back and forth by hand while making adjustments at the rear wedges to determine brake drag. You don't want much drag. After the rear brake adjustments at the rear wedges have been made Move to the front. With jack stands under the front axle, adjust the front brakes at the wedges until the brakes lock and back off as needed .You can check brake action by spinning the wheel and moving the brake lever by hand before connecting the brake rods. After the front wedges are adjusted, its time to move on to the brake rod connections. If you want good brakes, BELIEVE me, forget about any exact measurement here!!!!!!! The brake rods need to all be adjusted at the clevis ends so that the clevis pins will just enter the pinholes with ALL slack removed. This setup will have the pedal at the top of its travel and ready to put the lining to the drum. There is no need to concern yourself about whether the rear brakes engage first, its built in. I guarantee that if the brakes are right or even have some wear this setup will give very good brakes. anything less will not. In testing and as new parts wear in, adjustments will need to be monitored I usually make panic stops in sand or dirt to gauge skid marks and adjust as needed.