Brake Booster Pushrod Adjustment

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73Swinger18

73Swinger18

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I'm installing a new booster and master cylinder on my '73 Dart. I looked in the chassis manual for an adjustment on the pushrod, but came up short. Does anyone have a reference for the gap to be set for this rod? Thank you.
 
I was going to post the same question as I too would like to know how to check the adjustment.
I just had my master cylinder rebuilt and I'm getting ready to reinstall it on my power disc brake 69 Dart. I think someone had a posted on how to adjust it, but I'm unable to locate it.

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I just put a newer set up in my car - I don't recall a "gap" - the rod sits upto and onto the plunger in the MC.. there is no real tension when your not on the brake pedal, but there is no play either
 
I've seen some references for 0.020" gap between the rod and MC. I unthreaded the rod from the booster completely and inserted it in the MC. I measured the length of the rod inserted in the MC from the mounting flange. I then threaded the rod back into the booster and adjusted it just shy of the length measured earlier from the flange of the booster. This should get it close. You want it so it isn't pushing the cylinder dragging the brakes and also don't want a large gap creating a soft pedal.

Got A Soft Pedal? Don't Forget The Booster Pin to Master Cylinder Gap
 
73Swinger18
That's the article I now remember seeing before. Thanks for putting up the link!
 
I extend the adjuster outward and hold the MC against the booster until I feel the rod touching the MC piston, note the gap and repeat, screwing the rod tip in each time. You don't want much play because that would give "lost motion" in your brake pedal. But, you also don't want the rod pushing the piston in much either since too far and the piston won't return enough to expose the "fill port". Many people have issues with that, usually from having the pedal bottom out against the brake pedal switch. Always loosen that switch and adjust it when done. You don't want the switch preventing motion of the pedal, only sensing it. Seems obvious, but many never consider that.
 
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