Replacing master cylinder in 58 apache

[62lwbc10]

Hey guys how hard is it to replace the master cylinder? My pedal is going to the floor and the pedal is not returning and im assuming I need a new master cylinder. Looking for any advice on how to do it. THanks alot.
Mark

[Daze57]

its not really that difficult . but i am guessin' that you could rebuild it . there are kits available to do that ; most of the major vendors should have a rebuild kit . if not that route you prolly can buy a ''new one '' not sure of the cost .also if you decide to pull it and rebuild it yourself make sure you use plenty of p b blaster or wd 40 to loosen all the bolts and fittings .And make sure you have the correct wrench to lossen up the brake line fittings - good luck with your project .

[mr48chev]

WEAR GOGGLES or a face shield as you will knock plenty of rust, dirt and other crud in your face unless the bottom of the truck is spotless.

Unless the bore on the cylinder is pitted beyond honing out I'd rebuild it as they usually take a rebuild pretty well.

When you go to pull it take the brake line loose first as it's just easier that way and use a brake line/tubing wrench if you can get your hands on one. You stand a lot lower chance of rounding off the nut part of the fittings that way. One of the TF guys might have photos of what one looks like and what you have to take loose to get it out.

[_Ogre]

seeing as the truck is new to you i'd inspect the whole system
look for leaking wheel cylinders and lines, personally i'd rebuild everything

the mc has 1 line, 2 bolts and the pedal attached to it, easy peasy
of course easy goes out the window when you try to get the rusty line loose

[62lwbc10]

THanks guys for the advice. I would like to buy the correct brake line wrenches for this job, can onyone tell me exactly what wrenches I'd need? One other thing - I will need to bleed the system, can anyone give me any tips on this? I have the service manual but it would be good to hear from pointers from you guys. Is there a step by step thread perhaps that would be useful to me?

THanks alot
Mark

[booger1949]

have you thought about upgrading to a newer style mc while your at it, it would be cheaper an alot safer, i do that on all the old truck i work on, just my 2 cents worth

[OrrieG]

5/8, 9/16, 1/2 and 7/16 will cover most conditions. Get individual wrenches because the male and female connectors are usually one size different for line sizes. I would agree with upgrading to a dual MC, adaptors are easy to get and you have everything apart so it is the same amount of work. While you are at it you could even upgrade to a power unit too.

[_Ogre]

Originally Posted by OrrieG

5/8, 9/16, 1/2 and 7/16 will cover most conditions.

those will disassemble 99% of these trucks

[trucktony]

I allways use a vise grip,and the only wrenches you can use are half open box wrenches.
IF IT'S OLD:
Sometimes it's better to saw thru the small line right behind the mc so you can use a closed box wrench and make a new line because you would wreck the allen head anyway.
Allway's be patience and try to tap it loose both directions.
Usually it snaps loose in a sudden, but is still frozen to the line which will be turned to bits.
So all your precautions are out the door.
So, just cut it get it out and fix in your vise.
The 3way split can be held with a Bahco wrench(or the vise grip),so you can turn the nut out that was left at it with a closed box wrench

When in good condition.
Allways gently tap loose with a half open box wrench.
The opening slides exactly over the line
They are specialy made for this.
They can safe you a lot of time.
when the allen head is a little damaged I use a metric wrench.
Usualy they are just a little smaller then the american standard size.
Tap the wrench on and it has "bite"again.
It's allways better to think twice then spending a afternoon drilling and tapping new threads.