64 master cyl

[Stephen W.]

The build date for my car is 4/09/64 C2 coupe. Non power brakes. The master cyl in it now has the wrong top ( thunmb screw like a 63)
I assume someone replaced it with a rebuilt unit sometime in the cars life and the original went for a core charge. Where are the date codes and how would I read them so I can find a correct one for my car. part #?
What would be an acceptable date range for my car (6 months?)
I'm going to Carlisle in April and hope to find a good core.

[Joe L.]

Re: 64 master cyl

Steve-----

"5464264" is the casting number you're looking for. I don't recall if these things were dated, or not. If they were, it may be a date with only month and day.

[Stephen W.]

Thanks Joe *NM*

[Bob R.]

Re: Thanks Joe

Steve,
You might find you can sell that 63 master cylinder for more than the cost of the correct 64 MC. The 63 unit is a one year only Corvette only part.

[Scott Butville]

Re: Thanks Joe

There's quite a bit in the archives about '64 master cylinder date codes and the consensus seems to be that they are Julian dated. It's been quite a while since I last saw anything on the subject, but I have continued to ask every '64 owner I meet. I still have not run across anyone who has ever seen a '64 MC with the MDDY date code format as described in the TIM&JG. There are two MC's for '64 that both use the same casting. The power brake part has a bleed fitting; the non-power brake part does not.

[Verne Frantz]

Re: Thanks Joe

Minor correction Bob,
The '63 Corvette master is EXACTLY the same master as used on '63 Passenger cars with the metallic brake option.
As for dating, most of the '64 masters I've seen were using Julian dates cast into the underside of the bowl.

Verne

[Mike L.]

Re: Thanks Scott

Scott, I also have never seen the date coded per NCRS Judging manual, I have a few 64 master cylinders power and non power, all are dated in the julian style. The next time I see Carlton we should talk about it.

[Stephen W.]

Re: 64 master cyl

Thanks for all the responce. I checked the numbers and found the following under the bowl. 5462389 with a little split circle cast after it. To one side of this number are the letters "RS" or R5 and on the top in front of the fitting is 7/8. Like I said earlier I assumed it was a 63 because it does not have a bail but a thumbscrew holding the metal lid down.
I would like to be able to identify what I really have so I can exchange it for a good 64 one. Maybe I can help someone who needs this one?

[Joe L.]

Re: 64 master cyl

Steve---

The "5462389" casting number identifies this as the 1963 Corvette master cylinder.

[Jack H.]

Corvette?

How does the '389 casting differ from that used on Chevy passenger cars with metallic brake option in '62-63?

[Joe L.]

Re: Corvette?

Jack-----

It doesn't differ, at all. The same master cylinder was used for 62-63 passenger cars with metallic brakes as was used for all 1963 Corvette, except J-56.

[Joe L.]

Addendum

By the way, while the casting number does identify the referenced unit as a 1963 Corvette master cylinder, I didn't mean to imply that it was unique or exclusive to that application. Just that it would identify a 1963 Corvette master cylinder. Whether it "started life" in the Corvette application, the passenger car application, or, even, some other application that this casting may have been used for, is an "academic" point and of no particular import, at all.

[Verne Frantz]

Re: Corvette?

Hello Jack,
Actually, the '62 Passenger metallic master cylinder was unique to that application, and was not the 389 as '63. It was a 7/8" bore, but without the cast boss on the nose facing the engine. The underside was cast with the "7/8" rather than on the top of the nose. It was also the thumb screw design.
I'm sorry, but I don't have the casting number in front of me now (or committed to memory)...

Verne

[Stephen W.]

Re: Corvette?

Thanks to everyone that contributed. With your help I have located one that has the correct part # for my 64 as well as the lid with a Bail. It looks like it needs a complete rebuild but the price looks good. I plan to bead blast this unit to remove the rust from it but I'm concerned about the finished look. What would be the best way to restore the body of it and what would be the proper plating finish for the cap & bail.
I may just send it out to White post but they have not responded to my e-mails for a price quote yet. My other option would be to have the local maching shop over bore it for a brass sleeve

[John H.]

Re: Corvette?

I wouldn't let a local machine shop TOUCH it - send it to White Post or Apple Hydraulics to get it sleeved by people who know what they're doing and have the right parts.