Master Cyl Push Rod

1970 Challenger power brakes with disks on front. Every single brake component rubber and metal is totally new, car just finished restored. Problem Im having is I have brake pedal showing good pressure, not going to floor at all. I can pump and bleed front brakes with no problems, fluid shoots out showing pressure. But regardless, when pressing brake pedal after bleeding I get no front brakes, you can turn tires by hand. I have replaced the new calipers, proportion valve and master cyl with another set of new ones. Same result. I'm told that the master cyl push rod may be out of adjustment. Anyone know what procedure is for adjustment?
Thanks.

did you bench bleed your master cylinder?

Is the brake failure warning lght on? The pressure differential valve in the PV may not be centered, blocking fluid to the front brakes.

Yes, both of the master cylinders I have tried have been bench bleed. When I bleed the front brakes the fluid is plenty and nothing seems wrong, but stand on the brake pedal and the rears work, but nothing happening with the front unless you pump and pump the pedal and then some braking starts to happen on the front. Acts just like its air, but I have a river of brake fluid from bleeding the front, and no air is showing during bleeding, just pure fluid shooting out both sides in a volume that is normal. I then got a bran new disk brake proportion valve, its also got the secondary valve to equalize pressure to the front brakes. I'm no stranger to mopar brake systems, worked on them plenty. This one stumps me, never had it do this before and every component including lines are bran new. That's why I was wondering if the push rod which is adjustable has a process for checking its right. Not sure what else I have left to try?

Actually I have not checked to see if the light comes on, I have the battery disconnected most of the time. Not for any reason related to the brakes, I just prefer not having it connected when parked in my garage. I will see if it gives me a light or not. Thanks.

Not trying to insult your intelligence or anything but the more I think about your problem are you sure you plumbed the front brakes into the rear resevoir sp? on the master cylinder? If the whole system was new that would be an easy mistake to make. Maybe something to check... Good luck!

No problem with the intelligence lol...and actually I got my suspicions. The old one and the last new master cylinder looked the same and had F and R clearly indicated on the ports. This is my second new cyl and its different, its larger with no indications of F or R. The part number on the box is correct for what I need, but I wonder if the master cyl that arrived in the box was correct in relationship to the part number. This has been bugging me, I need to check it for correctness again before concluding its not part of the problem. I can say the larger of the two reservoirs (the rear one) is feeding the front brakes. This is usually normal to what I remember? But I'm now suspicious of the master cyl itself, I may have been given the wrong one overall. I'm going to get this doubt cleared up before fighting it any further. Appreciate the help. Thanks.

Hum...check and make sure the caliper is mounted correctly. Lube the pins etc. Also disconect the hose to the caliper & rebleed, push the piston back in & then bleed again. Piston should move back to the rotor. Just a few things I have run into. I have bought new defective calipers that were stuck & bad hoses. God luck

Did you put the calipers on the correct sides? The bleeder screws will not be at the tops of the caliper resivoirs if you have them reversed. Sounds stupid, but I have seen it done.

buy some brass plugs at your parts house & plug the M/C & if it is good(and bled) the pedal will be rock hard & virtually no travel. then take out (1) brass plug & hook up the line to the port next to the firewall & bleed them(your front discs) out & see what you get(for fluid and travel) and if it's the same then take off the 2 lines for the front brakes at the prop valve & plug the 2 ports on the prop valve w brass plugs & this will tell you if the prob is in the prop valve or downstream in the front calipers. EDIT on prop valves w the pin dont you have to pull it out(or in) to bleed the fronts?

I agree check the bleeders are on top.You can bleed a gallon of fluid and still not have brakes.Dont ask how I know.Rocky

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b EDIT on prop valves w the pin dont you have to pull it out(or in) to bleed the fronts?

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No, the pin should be left alone unless you are pressure bleeding through the master resivoir. Then the pin should be pulled out - and there is a little paper clip type tool for that. Not too many people pressure bleed through the master anymore - more of a dealer type thing as it can be a one man job and speed up the over all process. - beat the book time.