VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Master Cylinder

Going back a number of pages I do not see anything in previous posts about removing the master cylinder on a '37 master deluxe. I did one lying on my back on the garage floor on a business coupe twenty five years ago. Now I have the use of a hoist and can't remember how I did it. Point is I have everything off but I cannot get the clutch and brake pedals off. Does the shaft holding the pedals to the front of the master cylinder come off, and if so How? Shop Manual, as I have said about other things before, is rather non-specific about removing the master cylinder(four lines in the book).

Monte3
It is 30 odd years since I pulled the master cylinder off my 38 but I think the cylinder bolts are accessible from underneath the cylinder, disconnect the pipes and flex them slightly to allow removal without shifting the pedal unit.
Tony

I just removed the M/C a few months ago when I upgraded to a dual-M/C.

The first thing to do is to remove the pedals by removing the screws & nuts (one each) that secures the pedal shafts to the arm that's on the M/C. This screw & nut can be accessed by lifting the driver's side hood and looking for the pedals on either side of the steering column. As I recall, it's a 3/8 bolt (9/16" wrench). Remove the hex nuts and the bolts - just loosening the nut won't do it, since there is a groove on the pedal shaft that prevents the arms from disengaging if the nut becomes loose. You may also have to pry the 'split' on the end of the M/C shaft apart a slight amount and tap the pedal shafts out of the linkage.

The M/C itself has (2) bolts that secure it which can be removed from underneath the car.

After the M/C is out of the car, the arm can be removed by removing a pin that secures the pivot shaft. Once you see it, it'll be self-evident, I think.

Hope this makes sense.

Bob:
2nd reply to you on this thread. I appreciate the information. As I said I last did this twenty five years ago. Your explanation makes sense. I was going to work on it again today but as it isn't going to get into the high forties and football is on the tube, I will wait for tomorrow. Supposed to be in the fifties tomorrow, in the lower big mitten.
Thanks, Gary

Alright. Got the master cylinder rebuilt (kit from filling station). Now the wheel cylinders bleed well, large stream of brake fluid at each wheel and no air. The brake pedal still goes to the floor. I have an old Wagner-Lockheed master cylinder from many years ago. The master cylinder that was on the car, which is the rebuilt one, does not have any name on it. It has 'made in USA' on one side and a short series of numbers on the other. The master cylinder that I rebuilt has a pot metal reservoir cover and pot metal fill plug. When I tries to remove the fill plug it broke in half. I used the steel reservoir cover and steel fill plug from the Wagner Lockheed in the rebuild. One, why do I not have brakes if everything is new. Wheel cylinders were rebuilt, new shoes, drums turned, shoes adjusted properly and no leaks in the system. The second question is a little more involved. Inside the reservoir of the two cylinders they are not alike. The wagner lockheed cylinder has two holes that are nearly the same size. The one closest to the brake lines(rear of master cyl) soneone told me years ago is a bleed off valve or something like it. In any case they are nearly the same size. The cylinder that I took from the car and rebuilt has a much larger hole t the front. The rear hole is the same size as the wagner lockheed cyl, but the front one is approximately 1/16th to 3/32nd inchs in diameter. The brakes worked badly before I rebuilt them. Many years of accumulated junk had stuck the front pistons in the wheel cylinders, making the rebuild necessary. Thoughts on why I cannot generate a firm brake pedal would be appreciated.
Thanks, Gary

Perhaps you did not follow procedures in the bleeding of your system. The key item not mentioned was the closing of the bleed screw prior to you removing your foot from the pedal.

If you block off the exit port on the master cylinder can you still push the pedal to the floor? Or if on the bench can you still push the cylinder plunger more than a fraction of an inch? If either of those is yes then the master cylinder is not properly rebuilt.

Correct sequence for bleeding 1939 brakes is - First left rear, next left front, next right rear and the right front last. I do not have a 1937 shop manual but would assume it would be the same.
The size of the ports in the bottom of the master cylinder will make no differnce but the back port must be exposed when pedal is released. The etcentric bolt for the link adjusts this clearance.
The last person here that has that problem did not have the shoes adjusted tight enough.

Thanks for the information all of you guys. I have worked on brakes all of my adult life on 60's 70's 80's and newer cars. In fact I have never paid anyone to do a brake job for me in my life. You would think an older system would be easier to figure out! Brakes are adjusted properly. I will re-bleed in the sequence Gene suggested and check that pedal adjustment. Thanks again.
Gary

Brakes are good! Following Gene's suggestion for readjusting brakes and re-bleeding in the proper sequence, the brake pedal is very high and the brakes are good. Took her for a twenty mile round trip drive yesterday. She wanders pretty badly at low speeds, I presume because the the bad knee actions, but seems to be better at speeds above forty. Anyway, question is , someone plugged the head and cut off the tubing for the temp gauge and tied it off. Can someone recommend a reliable gauge repair service that can replace the bulb and repair the temp gauge?

The fact that it wanders would be more likely to be general play in the steering gear. An adjustment may help but the gears are usually just plain worn out on these models due to being driven many years with no lubricant in the steering gear.