My '57 98 Holiday coupe has the early car Bendix type master cylinder and power brake booster. Attached are a few photos of the final disassembly of the master cylinder. The compensating valve allows brake fluid to pass from the reservoir to the hydraulic cylinder. I then removed the residual check valve.

A NOTE ON PENETRATING OIL By using equal parts of automatic transmission fluid and acetone as a penetrating oil, the steel valve parts loosened with little effort. The only draw back to this is the acetone will evaporate if not stored in a sealed container. Use care as acetone will melt plastics and remove paint.

 

By ising various small wire brushes in my drill press I am able to clean up the bores in the master cylinder.

 

By using a 1/4-20 tap I cleared out the three master cylinder to brake booster attaching holes. A 10-24 tap was used on the master cylinder reservior cover holes. I used a bottoming tap after the regular starting tap. Since the booster attaching bolts were messed up, I will replace them with new 1/4 -20 bolts, as long as possible with flat and lock washers.

The third photo shows the resedual check valve passage from inside the master cylinder. I used an oil can to squirt some penetrating oil mixture into this passage to free the hyrdaulic outlet fitting from the master cylinder.

I will post reassembly photos as I progress with the rebuild.

 

We are standing by with baited breath...

 

I got a major flu bug and won't be back at it until Sunday at best. I will post my progress. Also, had to buy a repro '56 Olds chassis manual as the '57 manual only covers the Delco- Moraine units. The same holds true with the fuel pumps; only later car fuel pumps are covered the ones without the glass sediment bowl.

 

I hear you...just got over a cold that I had for thirteen days...usually takes about three or four....they're sending out bugs that are very buff, just like Arnold...

 

Hi,

Did we talk awhile back? Are you my good buddy John's friend?

 

Yes...the one with the scoops!!

 

Before the re-assembly begins, the 1957 and 1956 Oldsmobile Chassis manuals and a rebuild kit from Fusick Automotive were obtained. A holding stand was fabricated to hold the master cylinder/power booster assembly in it's correct position for final inspection and testing before installing the unit in the car.

 

Here are some of the master cylinder and power booster parts that have been cleaned and in some cases, painted. Two of the photos also show the old hydraulic plunger seals, washers and snap ring in their correct order of assembly. The rebuild kit has replacements for most of these parts.

 

The first parts to install is the Hydraulic Plunger assembly. Lubricate the seals with brake fluid and carefully work seal into the bore.

 

After the plunger assembly is in place, the tru arc ring is installed. Make sure it is completely in the ring groove. The plunger seal is placed in the bore next.

 

When the plunger seal is seated the O ring and master cylinder to booster gasket are placed on the master cylinder flange.

 

The residual valve parts are installed next. Use brake fluid on the seal and carefully make sure the spring and rubber valve is centered with the nut. The Compensating valve parts are assembled and installed next. Tighten the two nuts snug, but do not over tighten them.

 

With a new gasket the reservior cover is installed with the six screws. Snug up the screws evenly. Three new 1/4 - 20 hex head screws, flat and lock washers are used to install the master cylinder to the booster can. I used screws 3/4 of an inch long since I re-tapped the holes in the master cylinder with a bottoming tap earlier. A light smear of Anti-Seize is applied to the threads.

 

Now the piston return spring, return spring plate and "C" washer are installed. I used a telescoping magnet to hold the "C" washer and slip it in place. Trying to get both hands in the booster can while holding the spring back can be difficult. The magnet made the job easier.

 

nice work .....i'll more than likely be doing this this summer Thanks....Pics help me a lot

 

Hi,
Thanks a lot for the Manual, helped me a lot!!
But now, I’m struggling with bleeding. Tried to bleed just the Power Brake Hose (Master to junction) on Junction Block “A” Fig. 7-8 (Page 86-1954 Shop Manual), but there is not even air coming out.
Can this Junction be clogged?
I can unscrew the lower screw on the Junction – I’m not sure about the upper, is quite tight and I wouldn’t mess up this thing. Maybe I have to loosen the upper screw for bleeding and the lower is just a kind of dirt protection?
Followed the instructions from the 1954 Shop Manual – Engine not running (Page 95)
I do have pressure on the Brake Hose by the Hydraulic Master Cylinder (loosened it under pressure and Fluid splashed out), but just a few drops of Fluid coming out on the other side (tried to bleed the Hose by the Junction, but there is not enough space to do it proper).
My thought is to take the Junction out for checking, but I would appreciate if anybody knows something else.

Thanks for your help and greetings from Bavaria,
Monaco

 

Sometimes it's better to think befor writing, sorry for the question.
The upper screw is the bleeding one, worked perfectly got the air out.