Ok so I got 75 Newyorker spindles and a Chevy 7booster and master and stock rear drums rebuilt ...what's going on is the pedal is spongey and I am getting fluid out of all bleeders with good stream and no air ...also when we pump the brakes it builds pedal and when we bleed back the pedal depresses like normal but when bleeding the front we get pressure and nice fluid but the pedal doesn't move ...what I have done so far is put I a 10lb residual valve for the rear line and I have tested the master and master with front and all is good but when back is hooked back up to the master I have garbage for a pedal ...put vice grips on rear rubber line with a rag( I know I know ) and had pedal and then I adjust the rear drums as much as I could ( only bolt on each side is not stripped ) and the rear has a nice light grab to it but still can't get a good pedal and we also checked the ratio for the pedal assembly and had to modify it by bending it up to get a longer pedal and a 4 to 1 ratio that is called for and tried adjusting the stupid adjustment between the master and booster ...so this is where I'm at ...any ideas ??? I have to measure my bore on the master also and will do that next but the only thing I don't have is the block that comes off of the master but I have an adjustable valve for the rear to increase and decrease pressure and have tried messing with that a few time Sent from my iPhone using The H.A.M.B. mobile app
Here is my booster and master and here is the ratio we used for the pedal...now I know we are not perfect but we have full stroke and Idk what else I can try Sent from my iPhone using The H.A.M.B. mobile app
This is the bore and the size is what looks to be 1 1/8th Also the cap could be leaking so I'm getting a new cap tomorrow if I can find one local or just run to summit Sent from my iPhone using The H.A.M.B. mobile app
Anyone have any ideas??? Haven't been to bed today and still trying to work this out but I can't come up with what's wrong Sent from my iPhone using H.A.M.B.
Ok..this might help..get the specs for the 75 chrysler..proportioning valve , master etc...factory specs are what i go with...always works ....if master is down low residual vave up front ..2 lbs keeps the front pads in contact with rotors... ....no residual valve and the fluid bleeds back to master.....
I had similar problems with my Olds. I used a speedway 8" dual diaphragm booster and I think it was for a 60's GM Master cylinder. the pedal was mush. in the end it was two things. it was the ratio ( which seems you have worked on) I will say that I adjusted mine 3 times till it was right, and that was just drilling holes along the pedal and it was amazing what 3/8" movement made the pedal feel like. I also had to adjust the booster pushrod that goes into the MC as it was too short, so I had throw before the MC was being engaged. You can measure this by using some calipers to measure from the flat of the booster down to the top of the push rod- call is A. Then with the MC measure down to the bottom of the bore, Call that B, but you need to subtract the part that sticks up past the mounting surface. Call that C. B-C = A (roughly) However from your photos the piston looks to be quite high in the bore. If you want a firmer pedal a 1" bore will give you a harder pedal feel.
I spoke to a friend and he said the same and just keep messing with what you said till I get it right haha and it's almost perfect and front feels like it's not hanging up at all but gotta drive it a little to see ...the fronts a skittle rusty from sitting but between pedal ratio and the adjustment for the booster to the master and rear drum adjustment I think she's good Sent from my iPhone using The H.A.M.B. mobile app
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