64 Power Brake Master Cylinder Two Questions

[Larry M.]

1. From a post long ago I recall that the 64 MC was coated stove black but the judging guide says this is for 63 and that 64 was paintged semi gloss black. I'd like confirmation that is is paint and not stove black.

2. The guide says the date code is M/D/Y such as B 18 4 =Feb 18 1964. I have the one that came on my low miles car and one I bought NOS; both have julian dates. One is 274 and a mold cavity of 2; the other is 172 and a cavity of 1; Both have the part number with a D under it and are configured correctly. Both have the bleeder which was not on non power brakes.

The judging guide:
63 non power M/D/Y
63 power M/D/Y
64 non power Julian with no year
64 power M/D/Y

I'm guessing this last line is wrong. Any comment on this?

[Alan D.]

Re: 64 Power Brake Master Cylinder Two Questions

Will try to help, First - paint (not stove black)
Second, see picture It's not great but may help.
Would say julian date, and think I see your D along with the 1, but you will know better if location is the same.
Just can not get at any closer to verify, sorry.
Note: the MC is original to a Mar 64 car.

[Larry M.]

Re: 64 Power Brake Master Cylinder Two Questions

Alan, thanks. I see the mark next to the D but don't know what that is. It looks like a 4 under the Julian date which would be a mold cavity number I think.

[Richard G.]

Re: 64 Power Brake Master Cylinder Two Questions

I have a picture of what I believe is an original 63 master cylinder, no power. Unsure how it applies to your question except may assist in identifying the date code for early cars.



The numbers on mine are extremely difficult to read. Unsure how it would judge for this reason.
I understand GM use extremely inexpensive paint on the m/c that may have only lasted a couple of months.
From experience even good paint will not stay on long. Depends on the originality level you are looking for, if powder coat or paint is best.

But for durability I would consider powder-coating the m/c. Powder-coating holds up amazing well to the brake fluid.

If you are stuck on painting the m/c I would consider using one of the silicone style brake fluids just to keep the m/c paint from denigrating so quickly.