Still no brakes!

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These are the tools I used for the job; I removed the rear spring first using the brake spring pliers, then using the regular pliers, I removed both clips & pins.
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I just used my hands to remove the shoes, just lift up on the upper shoe to remove it from the cylinder slot and the whole thing comes out. Then I used the angled needle nose to remove the boot/piston taking care not to tear it, once you get a little bit of it off the lip of the cylinder, it comes off on it's own.
Burped the air out and install everything in reverse of how it came out.
Done.
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Not yet. I sent my bad booster to Mark A. and he'll be sending me a rebuilt one. So I'll have to install that and rebleed the system. Once that's done and the brakes are working properly, I'll be giving the Frontier a break for a while.
 
mydogpea said:
Well, I just was going off of what the Haynes manual said, "Using a suitable tool, rotate the adjusters through the backplate holes so that the tool tip moves in a direction from the wheel center towards the rim" This expands the shoes to firmly contact the drum. I've read in other threads that the tool handle moves from the center of the wheel outward towards the rim. Which is how mine turn. So maybe the Haynes manual is incorrect?

The Haynes manual is incorrect.
 
Not yet. I sent my bad booster to Mark A. and he'll be sending me a rebuilt one. So I'll have to install that and rebleed the system. Once that's done and the brakes are working properly, I'll be giving the Frontier a break for a while.

I'm pretty sure that if you can slide the MC forward enough to remove the booster and install the rebuilt one you shouldn't have to bleed the system again. There is no fluid transfer between the booster and MC.
 
Your springs are supposed to be on the backside of the shoe, that stops the shoe from collapsing in when you let the pressure off. This might be part of your problem?
Incorrect. The spring in front goes behind the shoes, the rear spring goes in front of the shoes. Also, that's what the retainer pins and clips are for.
 
My first impression is maybe your booster push rod is set incorrectly. Clearance should be 0.1 - 0.5 mm (0.004 - 0.020 in.) If your clearance is 1 or 2 mm that would cause the problem you have.

That new master cylinder may not be the same as the old one in that the booster rod clearance is no longer in spec.

The Toyota Factory Service Manual (FSM) shows a Special Service Tool (SST) that is used to set that clearance. I had trouble locating that tool so I made one and it worked perfectly. It's very easy to make one.:banana:

The boster push rod length is adjustable.

I'm concerned as to why your wheel cylinders adjust the wrong way. Where did you get them?

Six years old, don't know if anyone still uses or pays attention to four drum setups. All new wheel cylinders, the whole nine yards. Bench bled master cylinder. Ran about 3 qts thru the system today. Finally we notice that the master cylinder fluid level will draw down while pumping but return to full when the pedal is released. This is without cracking any bleeders. At this point I have put the old master cylinder back on (no problems with it) and will try again tomorrow. However, I'm curious as to why the fluid level would rise and fall in the master cylinder.
 
curious as to why the fluid level would rise and fall in the master cylinder.

The reservoir empties as the slaves fill, brake springs return it?
 
The old master cylinder is a single reservoir unit. The new one (that I took off because we decided it wasn't holding pressure) has two, the same size. Not very big. So watching it drop 3/4 while being pumped and then returning to full when the pedal was released was just unnerving. Are you saying it is normal?
 
The old master cylinder is a single reservoir unit. The new one (that I took off because we decided it wasn't holding pressure) has two, the same size. Not very big. So watching it drop 3/4 while being pumped and then returning to full when the pedal was released was just unnerving. Are you saying it is normal?

I just went through this. Got lots of great help from some people and after about a week I finally got them to work on one pump.

It takes a few pages of reading but I get it. Lots of good info here.

Goat. A 1967 survivor FJ-45 LWB
 
Are you saying it is normal?

Well, I'm just thinking here now, that can be dangerous, as that's the first time that this question has occurred to me. But, if you're forcing (brake) fluid down the lines, out of the master, into the slaves, to occupy the slave cylinder area, to force the shoes against the drums, than the fluid in the reservoir would decrease, right?
And then, when you are done braking and let off the pedal, the brake springs pull the shoes in, compressing the slaves, and sends the fluid back to the master, as it has nowhere else to go, hopefully.
so, I'm gonna think that's normal until Jim tells us the right answer.
Maybe, if you adjusted your shoes tighter, the fluid level change would be less?
 
Two gallons thru. All fittings and bleeders dry, no pedal. It won't pump up. I started this morning by checking each and every fitting and then used my Mighty Vac to go around, actually felt decent. My friend showed up and he went around all the fittings and agreed all were tight and dry. We started pump bleeding and the pedal never got as good as it was when we started. I would think that if one or more of the new wheel cylinders (Raybestos 7/8 rear 1 1/4 front) were leaking I would see fluid, I don't. Scratching my head, this should have been a one hour job.
 
That is my experience as well, tighter than you would "normally" adjust them. But, late this afternoon I decided that installing the old master cylinder didn't solve the problem. So I re-bled the new MC on the bench and put it back in and taped the threads on the vice grip fittings and installed them. Using the MityVac I experience the "usual" stream of fine bubbles that are generally attributed to pulling air around the fitting threads. So tomorrow morning I am going to tape all of my bleeders, put a smear of grease around them at the cylinder and stop pulling 10-15 Hg on the vacuum and use about 5 Hg and see if that improves the pedal, which now does pump up. Rain and darkness shut me down.
 
I had the same problem after complete replacement of entire system. The problem in my case and you are already on it was the air in top half of the wheel cylinders. "Burping" them did the trick.
 

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