Combination valve query
Thread Starter
Instructor
Joined: Nov 2020
Posts: 143
Likes: 28
From: Colorado Springs
Combination valve query
78 base coupe. Just finished rebuilding all four calipers with new flex hoses. Been reading a lot of posts on bleeding. I am a little confused about the combination valve . I know it acts as an electrical switch to turn on the dash brake light. When it slides in either direction to light the light does it also shut off fluid flow to the offending circuit or not? Do i need to use the tool that holds the shuttle centered in its bore during bleeding? I remember i bled the brakes a few years back and did not even think about the combo valve-just followed the prescribed FSM sequence.
Thread Starter
Instructor
Joined: Nov 2020
Posts: 143
Likes: 28
From: Colorado Springs
Just answered this query i think. FSM does mention the combo valve so i ordered centering tool. Also found a neat tool by Master Power Brakes that lets you bleed master cylinders by forcing fluid backwards through the outlets with a syringe. I’ll give it a try and report back.
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Cruise-In VIII Veteran
The tool doesn't center the valve. It holds it centered so you don't trip it while bleeding. Once you tripped it the tool won't work, to late. Stomping on the pedal will usually recenter it.
Pushing the fluid up works great. Air likes to travel up.
Pushing the fluid up works great. Air likes to travel up.
