I have new braided lines at the four wheels and steel throughout.
Not sure about the MC. I know it is not stock and I cannot remember what I purchased. Could be a chevy cylinder for all i know. Threw it in during troubleshooting years back. It is certainly bigger than the stock and has the ports on the left side instead of the right. No free travel in the linkage either.
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.
Gravity bled today and got a little air out but still have the same issue as before.
Double checked the linkage on the bell and the linkage is tight and no indications of wear. My issue is surely from the end of the linkage to the MC. Just does not look like it is moving the piston of the MC. Before installing and bench bleeding the MC I did check for smooth freedom of movement on the piston so that says what? I will try to adjust the end of the pushrod out a little more but beyond that I am at a loss. I need an expert over here or I can come to you. Come on locals chime in...
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.
I looked at my brake linkage (manual) and I have about 1/4" of travel pushing with my hand before I can't push anymore.
I can feel resistance from the very first movement of the linkage.
How far does your MC linkage travel before you feel resistance?
If it's moving a ways I would think perhaps your leaking past the seal cup in your MC
at the beginning of the stroke and not building pressure till the end of the stroke.
Did you have your MC apart and replace any of the internal seals?
The pedal starts in the released position at 42 degrees and engages the pushrod at 45. Max resistance is at 50 degrees (still no effective braking action). Max pedal movement (to the floor with MC removed) is 65 degrees.
I obviously should have more movement out of that pedal.
The MC was replaced new a few years back when troubleshooting this same issue so I had assumed it was not the culprit when the problem continued. Not I am not so sure.
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.
Damn Chuzie ... you have replaced everything.
Here's what I would do as a last ditch effort.
beg borrow or steal an adjustable proportioning valve so you can dial in front and rear bias on the fly ... Nascar style.
It might be that your valve and MC / brake system are not matched up and not balanced well.
See if you can make a difference by changing pressure from front to back.
Other than that I don't know what to do.
Every component of your system is new or has been checked out.
All I can think is the components are not working together correctly.
Adjusting the bias on the fly might fix it or at least give you some new insight.
Already did that. Replaced the stock prop and replaced with an adjustable in hopes of solving the problem but it is still no go. It was suggested I double check all my routing and consider the possibility that one of my hardlines may be blocked.
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.
To check for an obstuction open a rear bleeder, put a few feet of clear hose over the bleeder so the fluid goes up the hose. Check the rear axle first, then the front. We call that a one man bleeder. Clear fluid and if there are any bubbles they will go up the hose.
To be honest it reminds me of some of the master cyl swaps I have tried. If you get the wrong one (for smaller or lager rear wheel cyls) it can make your pedal travel down allot further to stop the truck. Keep in mind the master cyl is supposed to be matched to the rear wheel cyl and front (calipers or wheel cyl). If its incorrect it can give either a hard pedal with a short stroke or a long stroke and a soft feel. Wheel cyls are diffrent depending on the axle size (load rating). Double check what parts you have put in.
MIke, have you tried adjusting this tiny nut/stud in the center of this push rod yet? when i 1st went to power brakes and 4 wheel disc...i had the same stopping as you. had to pump the peddle2-3 times to get complete stopping power. I then adjusted the tip of the push rod out/in until i got perfect brakes. its simple and easy...i read your thread, but didnt see where anyone suggested that(maybe i missed it)
77 built 306,Trickflow Cam/Alum Heads/dome pistons/10:1comp,nv3550,duff long arms,3.5" lift,family cage,protofab rear bumper,twin sticked, and 35KM2'sG.D.I.
mokin:![[Image: sig2.jpg]](http://i288.photobucket.com/albums/ll176/mchuzie/sig2.jpg)
