Master Cylinder Swap

[Toyz]

That thought entered my mind but I dismissed it since it sounded as if it worked well before setting. If it is a drum/drum setup, it should have had 10 psi residual valves in both ports , which SHOULD have caused noticeable caliper drag from the start.
Paul

[ICEMAN6166]

does the pressure relieve itself when the truck sits overnight or does the calipers stay on until you crack a bleeder or line

[longcabjohn]

Open line where it goes into the rubber hose, if brakes do not retact the rubber hose has gone bad.


Johnny

[69supercj]

Got the new M/C installed and the brakes work good, have a "good" pedal right off and a real good pedal after one pump. No leaks at any of the fittings BUT the darned thing is leaking around the cap. I noticed that the top lip of the M/C was a wee bit pitted and came within a knats ass of turning it upside down and surfacing it on some 100 grit wet/dry but decided to go with it. Now I guess I'll have to try to smooth it out with some JB Weld. Other then that, all works well and no more drag!!!

[69supercj]

Well the JB weld didn't work so I took the M/C back off and ordered a new one. Hopefully it will be of better quality then the rebuilt unit that I had.

[ICEMAN6166]

Well the JB weld didn't work so I took the M/C back off and ordered a new one. Hopefully it will be of better quality then the rebuilt unit that I had.

i really hate when things like that happen.

careful inspection of parts while still in the store is a necessity these days.

[JRANGER]

I dunno if this helps but when doing a conversion on my 67 mustang a New Raybestos Dual Bowl Disc Master is used with a proportioning valve to adjust front/rear.

Just curious did the mustang MC directly fit or did you need a bracket? May do this on my truck as its already converted to front disc but its running single bowl stock unit? THat cant be good and i have the dual bowl MC sitting at the house.

[ICEMAN6166]

changing to the dual mc is fairly simple
you definitely need one with front discs
you can get a new proportioning valve ,either an adjustable type or a factory one from a truck with front discs.
the pushrod from the single mc is too short for the dual and the one from later trucks with disc brakes is 1" too long so must be cut down.

[69supercj]

I dunno if this helps but when doing a conversion on my 67 mustang a New Raybestos Dual Bowl Disc Master is used with a proportioning valve to adjust front/rear.

Just curious did the mustang MC directly fit or did you need a bracket? May do this on my truck as its already converted to front disc but its running single bowl stock unit? THat cant be good and i have the dual bowl MC sitting at the house.

The Mustang M/C bolted right up. I do need to make an adjustable push rod as my brake pedal is sitting about a half inch too high.

[JRANGER]

http://www.cjponyparts.com/scott-drake- ... /p/A21161/

[69supercj]

Thanks for the link but 43 bucks for a pushrod is a bit much in my book. I can make one for the price of a left hand die.

[ICEMAN6166]

Thanks for the link but 43 bucks for a pushrod is a bit much in my book. I can make one for the price of a left hand die.

get pushrod from 67-72 non power brake trucks, less than 5 minutes to cut off end and round off.