Installed 92 4Runner Calipers

[Slowerthanu]

And now I need a new Master Cylinder!

I was posting this to say that

1. Install was easy, trim a little off of the brake shields, grind a tad for the steering stops and thats it.

2. I need a new Master Cylinder, I understand the FZJ-80 is a good choice, what year would I need?

I have good braking power, but the pedal goes to the floor when I brake.

Thanks for suggestions, I will do a full write up with pictures as soon as I feel the brakes are worthy of one.

Dan

[Slowerthanu]

anyone, anyone?

[yoda]

I did the 95 4Runner master (1" bore). Front disks only (so far). Works great.

[cruiserbrett]

I doubt the master diameter is the issue. I have run 1" bore and 7/8" master(drum and disc cruiser ones) and never had an issue with the pedal going to the floor and I had the big 4runner/t100 calipers. I even had a short 15/16" forerunner booster and the pedal barely went an inch or two before you had good braking effort.

Are you running drums in the rear? Are they adjusted properly? this makes a HUGE difference when you change the bias of power front to rear. do you have a residual valve in the rear? the strong rear drum springs can retract the shoes too much if you dont have the correct drum residual valve.

If your running discs rear, do you have the residual valve? rotor run out can retract the pads a bit requiring a bit more pedal travel to engage if there is not a residual.

"Guppie" on the board has a 72ish drum master/booster running the t100/4runner calipers up front and GM discs in the rear and it stops beautifully, but it did require a prop. valve and some time to bleed. Not even close to bottoming the pedal.

Brakes are simple.

[Slowerthanu]

Drums rear, recently adjusted as per FSM. I gravity bled and pressure bled for around 4 hours today, I also bench bled the Master to be on the safe side. the 77 M/C is a .87 bore as far as my research has revealed. The 95 4Runner is 1.00. I will try adjusting the rears again.

BTW, what all could knock the rears out of adjustment?

Dan

[Slowerthanu]

Originally Posted by cruiserbrett

I doubt the master diameter is the issue. I have run 1" bore and 7/8" master(drum and disc cruiser ones) and never had an issue with the pedal going to the floor and I had the big 4runner/t100 calipers. I even had a short 15/16" forerunner booster and the pedal barely went an inch or two before you had good braking effort.

Are you running drums in the rear? Are they adjusted properly? this makes a HUGE difference when you change the bias of power front to rear. do you have a residual valve in the rear? the strong rear drum springs can retract the shoes too much if you dont have the correct drum residual valve.

If your running discs rear, do you have the residual valve? rotor run out can retract the pads a bit requiring a bit more pedal travel to engage if there is not a residual.

"Guppie" on the board has a 72ish drum master/booster running the t100/4runner calipers up front and GM discs in the rear and it stops beautifully, but it did require a prop. valve and some time to bleed. Not even close to bottoming the pedal.

Brakes are simple.

I believe the 72 is a 1 inch bore also.

[yoda]

The 71 I took out was 1"......I just liked the look of the single reservoir.

[mantis]

Get the rockstomper GM 1-ton master/toyota adapter. $95.

http://www.rockstomper.com/catalog/b...mtoymaster.htm

[tornadoalleycruiser]

Hmm.. In trying to keep with the hardcore aspect of this BB..
When I installed my Big piston vented Calipers on my front axle with the widening kit from Sky after I installed my Profields and ARb adn fine spline ring and pinion and Pig inners in that same axle along with New knuckle studs from Marlin, I used a t100 master cylinder. I believe it is 1 1/16 bore. Actually took more pedal pressure with regular 76 calipers up front so should be just fine with the bigger 4skinner calipers. I haven't driven it yet cause I flipped my springs around and my front fenders had to go. Gotta fire up the tubing bender in the corner and make new ones..
Yeah I can play hard or soft!
But this is another cheaper option cause the t100 or similar should be found in a junkyard thus grab the master.. They're alum so shouldn't ever pit and need to be rebuilt other than the rubber seals inside.. I haven't killed one yet and run one on my FJ62 that has 4wheel disk and my FJ40 that has 4wheel disk. Use your old masters for those Restorations in the garage The stock master went on my 64 FJ45!

[cruiseroutfit]

Originally Posted by mantis

Get the rockstomper GM 1-ton master/toyota adapter...

Also available here in SLC Dan, might be an option to check into... just installed one on a LC axled'd rig (the yellow 40 that was up at the Pig Run) with OK results.

[Slowerthanu]

Update:

This morning I bench bled the m/c again, rebled the brakes front and rear and adjusted the rear brakes, I may need new rear brakes though, I set the cyinders out to maximum per fsm and had no change there was zero drag on the rear brakes at any time and now as awesome as it may be, my pedal goes all the way to the floor. AWESOME (sarcasm).

Any suggestion or should I go back to plan A and look for a new m/c

Dan

[tornadoalleycruiser]

Just a suggestion of a commonly overlooked thing in older brake systems.. But have you replaced your drop hoses and flex lines on the front axle yet? Those get old and the inner hose can swell taking pressure away from your brakes. I'd go to Brians site and order longer drop hoses if you replace them. WE had one truck that we coudn't get brakes to grab till we replaced those. Fold that old hose over and look at the cracks in the rubber, It'll scare you and should!
Second.. New master with more volume for the larger piston front calipers, but your not getting fluid to the rears? Right? You had stopping in the back before? With the 2 seperate chambers in the master your rears shouldn't have been affected as much as the fronts.. Someone that knows brakes better might be able to help.. I know phil johnson just went thru a similar situation on his truck.

third.. Throw away the rear drums and go disks.. The montecarlo calipers don't use as much volume as the rear drum cylinders and might be an option as well.. Probably won't work with your setup but might..
It's weird that changing the fronts affected the backs.. But I know nothing about my rear drums on any truck cause they're all gone and sport disk..

[Pin Head]

Originally Posted by Slowerthanu

Update:

no change there was zero drag on the rear brakes at any time and now as awesome as it may be, my pedal goes all the way to the floor.

Dan

Does the pedal level come up when you pump it? If so, then the brakes aren't adjusted properly. Lengthen the adjuster until the shoe is tight and then back it off a couple of clicks until there is a slight drag.

[tornadoalleycruiser]

If you get no pedal after a pump or so? Might be a blown piston in the master? Maybe try putting a bleeder screw in the front circuit and see if you can get the rears to work only, then do the same with the fronts? Just ideas, not necessarily the right ones and I wouldn't drive like that but we've gotten people home and off the trail with fixes such as this one..

[Slowerthanu]

Entire brake system uses braided steel lines.

Brakes were actually acting kind of funny (too much pedal travel) before the new calipers (I ripped a hard line off in moab).

When adjusting the rears, I put them out to maximum and got zero drag on the brakes.

I am going to use this winter to upgrade the m/c and put discs on the rear.

[tornadoalleycruiser]

"I am going to use this winter to upgrade the m/c and put discs on the rear."

It ain't winter yet.. So I'm guessin you still have wheeling to do before you tear it down! Try the master block off trick.. Sounds like you've tried to eliminate most variables, Got a spare master lying around? They aren't that much at parts stores.. Rebuilt A-1 is like $40.. I think I normally pay about $25 for a t100 master complete used..
The rear pistons aren't leaking I assume? And the new hoses didn't fix your problem..
Is this on an FJ40? or something newer that might have a LSBV like an FJ62?

[Slowerthanu]

Originally Posted by tornadoalleycruiser

"I am going to use this winter to upgrade the m/c and put discs on the rear."

It ain't winter yet.. So I'm guessin you still have wheeling to do before you tear it down! Try the master block off trick.. Sounds like you've tried to eliminate most variables, Got a spare master lying around? They aren't that much at parts stores.. Rebuilt A-1 is like $40.. I think I normally pay about $25 for a t100 master complete used..
The rear pistons aren't leaking I assume? And the new hoses didn't fix your problem..
Is this on an FJ40? or something newer that might have a LSBV like an FJ62?

Master is not losing any fluid, I am going to hit the pick and pull this weekend in search of a T-100 or 92-95 4 Runner master.

[4x4Poet]

I don't think anyone has mentioned looking at the mas cyl push rod adjustment.

Since the rears are origs, are the drums within spec? That is, not turned past the max allowed. I expect the shoes appear fine, since they'd have to be in the rivets to not have much adjustment left.

May I suggest you have someone gently apply the brakes with one rear drum off so you can check for top and bottom shoe movement. Could help ascertain whether what happens at the pedal gets translated to the rear, hydraulics wise.

[theSherpa]

1985 FJ60, rear drums, swapped '92 4WD 4Runner calipers on with no other changes, system was in good shape before swap...have somewhat more travel in the pedal (maybe 20%?), but no way does it "go to the floor". when my back brakes get to needing adjustment, pedal travel goes way up...I'd say you have (and have had) issues with back brakes having too much travel getting shoes to the drum, and the new calipers fluid demands have pushed it over the line from marginal to unacceptable. sounds like bigger master will just mask a problem elsewhere in the system to me. swap some other drums on...I think Walt's advice is good. just my $0.02.

Steve

[Slowerthanu]

well, tomorrow I will inspect the rears closely and update. I have had that feeling too.

[Slowerthanu]

Re-adjusted the rears and that helped alot.

Installed a 93 4Runner M/C and holy poop! It stops like never before and the pedal feels absolutely wonderful.

Dan

[yoda]

Gotta love good brakes! That was my feelings the 1st time I hit the brakes after my swap, but I had done the calipers and master at the same time.