1963 Master Cylinder Question

[Joel T.]

Hi all;

Question on my 1963 master cylinder (non-PB), actually the push rod which connects to the brake pedal arm... Is this rod adjustable??? I see from pictures that it appears that the rod can be adjusted in length... Is this correct, and if so, is there a procedure to do this??? My symptom is extended pedal travel even after manually adjusting the brakes... A second symptom is difficulty in bleeding the system... I've comes to learn that I really need to pump the pedal totally to the floor to get any sort of pressure in the system... unless I do this, the fluid does not flow through the lines.

Thanks!!

Joel

[Harry S.]

Re: 1963 Master Cylinder Question

Joel, yes the 63 MC is the only one that is adjustable. As I recall 1/4 turn on the nut will give 1/2 to 1 inch of movement on the pedal. To do this pull the MC away from the firewall and the adjustment nut becomes visible.

Also, look to see if is leaking from the rear seal by the piston. If it is, bleeding the brakes becomes difficult.

[Joel T.]

Re: 1963 Master Cylinder Question

Harry;

Ahhhh, thanks! This explains a bunch of things. The MC was rebuilt this past winter so I know it is OK... actually I've had this problem before the rebuild...

Let me dig under the dash and see how to make this happen... I'm guessing that I need at least 1/4 turn perhaps 1/2 to get this right.

Regards,

Joel

[Harry S.]

Re: 1963 Master Cylinder Question

Joel, I have a P/B car and I can't get at the nut from under the dash. I have to pull the MC away from the P/B booster to get at the adjustment nut.

[Bob R.]

Re: 1963 Master Cylinder Question

I was a little confused by Harry's explaination. I believe the pedal height can be adjusted under the dash. There is a nut holding the push rod at a set dimension. Loosen the nut and adjust the push rod. No need to remove the master cylinder. No power brakes on my car.

[Joel T.]

Re: 1963 Master Cylinder Question

Hi Bob;

Thanks, I understand... I think Harry was telling me to check the MC to make sure that it was not leaking... in reference to my question on bleeding brakes.

Regards,

Joel

[John H.]

Re: 1963 Master Cylinder Question

Joel -

Don't over-adjust that threaded clevis - make sure you have the required 1/16" to 1/4" of pedal free travel between the full "up" position (pedal arm against the rubber bumper) and the point where the pedal pushrod contacts the rear piston in the master cylinder when you depress the pedal. If you don't have the required free travel, the piston seal can cover the compensating port, and the brakes will drag. See UPC 5, sheet 4.00 in the 1963 Assembly Manual.