Leaderboard

My '71 240z has a metal check valve with a rubber isolator around it. It is not plastic or black and grey like the ones being sold now. I removed it to double check that it was installed correctly and it was, on the booster side of the valve you can blow air through it and on the intake/engine side you cannot. My question is, how much pressure should it take to open the valve inside? On mine when I blow in to it, it takes some strength to overcome the valve. When it does I can feel it closing or thumping inside. It is not smooth but I do not know how it should be. My car has always stopped fine with plenty of pedal feedback but right now I am working to diagnose why my front brakes are sticking and I am doing a check of all the components. Any feedback is greatly appreciated regarding the proper action of valve.

As a diagnostic procedure; when the brakes are stuck, open the bleeders on each caliper and see if any fluid squirts out. If so, and then the car will roll easily, the pressure is being held in the lines. If not, then the calipers are stuck for some reason.

Holy crap! I guess I should insure my glovebox door!

Have fun C'man - http://www.classiczcars.com/topic/49754-throttle-opener-control-valve-and-servo-diaphragm-for-a-240z/

Monroe's How To Rebuild book says .020" is the most you can shave before needing cam tower shims. Can't remember standard head thickness so can't do the math for minimum.