63-64 Master cylinder identification

[David Z.]

What are the correct numbers/markings for a 63-64 corvette standard master cylinder? The reference that I have does not include master cylinders. Thanks.

[Harry Sadlock]

Re: 63-64 Master cylinder identification

Dave, they are visually very different. Please let us know if your looking for a 63 or a 64 as the 63 is a one year only.

Harry

385113

[Mike M.]

Re: 63-64 Master cylinder identification

both have 7/8(pass cars have 1) debossed in the snout of the cylinder casting. 63 lid attaches with thumbscrew, 64 has a bale wire to secure the cap. mike

[Tracy C.]

Re: 63-64 Master cylinder identification

Dave,

63 master cylinder is casting number 5462389 with a thumbscrew lid. the 64 is casting number 5464264 with a bail wire lid.

Both have a 7/8 bore.

While we are on the topic, I have the prettiest unrestored 63 casting I've ever seen for my July build 63, but the casting number preceedes my car's build date by about 9 months (Oct 62). I know the "approved window" is about 6 months.

How big of a point hit is this? Should I be looking for someone to trade with?

thanks,
tc

[Harry Sadlock]

Re: 63-64 Master cylinder identification

Dave, if it is a 63 that you are looking for, a power brake car has a few differences on the master cylinder. At first the power brake cars had master cylinders with the thump screw. The thumb screw sat too high as a result of the power booster and the thump screw was hitting the underside of the hood. Therefore, most power brake cars have a hex head bolt/screw to tighten down the master cylinder cap.

Also, there is an extra bleeder outlet on a 63 power brake master cylinder. It is located on the master cylinder, forward towards the front of the car, engine side.

Harry

38513

[David Z.]

Re: 63-64 Master cylinder identification

Thanks for the numbers. The project car I have is a 63 but it has the bail type lid on it. Does the 64 cylinder have delco or any other name on them. I trying to determine if the cylinder I have on the car is an original or reproduction. Thanks

[Tracy C.]

Re: 63-64 Master cylinder identification

Yes, 7/8 is debossed into the front nose of the casting and the Delco Moraine logo and a casting date (MDDY as in 6124 for a June 12 64 casting) is on the bottom.

tc

[Scott Butville]

Re: 63-64 Master cylinder identification

TC, Have you ever actually seen a '64 master cylinder with that date code format? Take a look in the archives at previous discussion on this board on this topic. Some folks believe the TIM&JG is incorrect and they were actually Julian dated.

[Tracy C.]

Re: 63-64 Master cylinder identification

Sorry Scott, I've never actually seen a 64 casting date format. My 63 however does use this format.

tc

[Scott Butville]

Re: 63-64 Master cylinder identification

Tracy, Thanks, my search will continue.