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tchevs · 08-10-2020, 08:26 AM

As an update i was able to work on it a little yesterday. Separated the master from the booster to take some measurements of the pushrod. Turns out that with the pedal to the floor, the pushrod travels about 1 inch. With some measurements at the pedal, I figured that the rod will travel more if the rod was set lower at a 4:1 ratio. I drilled a hole 3-3/4" center to center from the upper pivot. The pedal now travels 1-5/8".
I was looking at the cutaway for the prop valve and got to thinking, since its a little difficult to get to, why not just test the switch for continuity to see if the valve has moved to one side? Isnt that what that valve and switch do? If the valve moves to one side the switch closes and sends a ground to the brake light on the dash right? If theres no continuity the valve is centered.

08-10-2020, 08:26 AM	#23
tchevs Registered User Join Date: Feb 2017 Location: Castroville California Posts: 492	Re: Manual to power brakes on 1961 Apache As an update i was able to work on it a little yesterday. Separated the master from the booster to take some measurements of the pushrod. Turns out that with the pedal to the floor, the pushrod travels about 1 inch. With some measurements at the pedal, I figured that the rod will travel more if the rod was set lower at a 4:1 ratio. I drilled a hole 3-3/4" center to center from the upper pivot. The pedal now travels 1-5/8". I was looking at the cutaway for the prop valve and got to thinking, since its a little difficult to get to, why not just test the switch for continuity to see if the valve has moved to one side? Isnt that what that valve and switch do? If the valve moves to one side the switch closes and sends a ground to the brake light on the dash right? If theres no continuity the valve is centered.