71 disc brake conversion problems..help

[chuckee]

i did a front disc brake conversion from a 81 fj60...and a rear conversion from jt outfitters..i bled the brake lines and i have rear brakes ok, but the front calipers dont put enough pressure on the pads to do any good...anyhelp would be appreciated.also installed new brake booster and master cylinder..
chuckee

[Pygpen]

Welcom New-b!
Did you "bench bleed" the master first?
Did it have good flow from the front output?
PMK

[lc tpi]

just wondering if the rear locks up when you get on them, asking this because most disc swaps on the rear reqiure a proportioning valve to cut the pressure down on the back to equalize the pressure front and back. i have discs on the back and have one. i turned it down to when (im emty of all gear except usual stuff )the back just starts to lock up but doesnt. this could be the problem if you dont have one. also the rear brake port on the master cylinder has a residual valve in it that keeps pressure in the line for the drum brakes. if this is still in there it can cause the discs to drag. hope this helps.

[ROCK HUGGER]

Did you pull the residual valves out of the master?

[chuckee]

i dod not bench bleed the new master cylinder...matter of fact i didnt know you had to bleed the master cylinder...as, i have enough pressure on the rear disc's..its the front calipers that arnt working properly...the calipers do squeeze a little but not enough to stop the truck.......i will attempt to bleed the master cylinder, and hope it is the problem..any other ideas?
chuckee

[warpdriv]

Did you get the same year master cylinder? I put a 85 Supra on my 70 FJ40.

[65SWB45]

Here's a thot. Don't try this for any distance away from home tho. Try plugging off the rear brakes and see how the front brakes by itself without the hydraulic resistance of the rear possibly affecting the piston travel inside the master.