FJ60 Master Cylinder upgrade

[Brian Worthan]

I have a 1984 FJ60 with the TSM rear disc brake conversion kit installed. Have installed new pads and the rotors are within spec. Calipers were completely bled (pressure bled it) and the parking brake adjusted up. Problem is the brake pedal travels a long way (almost to floor), is spongy (like air in lines) and the brakes are not adequate (can't lock them up). Local mechanic believes the original master cylinder does not put out enough volume to move the pistons in the rear "Eldorado" calipers enough to get adequate braking effect. Anyone have experience with the same problem. Is there a bolt on solution which would provide additional fluid volume? Would a M/C from a FZJ80 work (bolt on) since they came with rear discs (and might have more volume)?

 

[meluhha]

There is lot of info already on this in the Tech section and by using the search function (friendly hint...before the bashing comes). The short answer is yes, an FJ80 master cylinder should work. Look for a 1" stamp on the side. It's basically upgrading from 7/16 (maybe?). I pulled one off a '94 T100 when I upgraded to larger calipers on the front and it made a difference for me. Have no fear...others will chime in as well.
Cheers

BTW: Yes, it is a bolt on process, a one job. You'll have to bend a couple of brake lines and figure out how to connect the wires so your light doesn't come on all the time (I never did...)

 

[HZJ60 Guy]

There's a pic of the FJ80 master cylinder in my 1987 HZJ 60.

 

[sl33py]

would this be a worthwile upgrade even without modified brakes (ie - no rear disk - stock drums)?

 

[meluhha]

Definately wouldn't hurt! I'd imagine it would give your brakes a little more pressure = better braking. Probably not too noticable though...these MC can be found super cheap at your local pick-in-pull ($10-20). Ask for the T100 (93-95, 1-ton, 4x4--may be some other years too) instead of the popular 4-runner MC and you'll pay less.

Matt