I am in need of a correct master cylinder either rebuilt or on that I can have rebuilt for a 70 Stg car with a build date of 10D. Does anyone have one that they will let go? Thanks.
Have a good quantity of Cores. Drum or Disc. Most are clean Desert units. Five or Six power booster units as well. PM for information. Dave S. Las Cruces NM 88012
Gary's correct. Also: manual and power drum master cylinders have CT stamped on the little pad in the front. Power disk units have an EA stamp. I've seen them on eBay from time to time, as GM used them on other brands.
The power disc brake car uses the EA code master cylinder and that's the same master cylinder and code used for a '69 GTO and '69 Grand Prix. They are somewhat easy to find. The casting number on the side of the master cylinder is 5468309. A '69 Chevelle uses the same master cylinder as well but it has a BA code instead of EA.
I Brett, I've always thought it was strange that the Buick repair manual calls for CT code for both manual and power drum brakes but looking at original cars shows that one has bleeders (power brakes) and the manual brake car does not have bleeders. I know you've studied this topic, so what do you think? I think you answered your own question. GM had lots of crossover stuff to prevent parts shortages. Another mystery is why did Buick carry over the double bail disc cylinder until 1970 when Olds a stopped it a yeat or two prior because they went to single bail? We're hijacking this thread.
2.5 won't mind if we hijack the thread, he's a good guy. The casting date code is on the driver side under the front bail but it's sometimes hard to read. This photo is an EA master cylinder that's on eBay right now. I had a EA master cylinder rebuilt at White Post about 6 months ago and it was $225 plus shipping. Turnaround time was pretty good. I specifically requested for them to NOT paint it so I could use the paint I want, rather than the paint that they might use. btw, they were black when new, not natural cast iron.
Dave . I'm interested in the one with the bleeders and the blue dot . And the one with no top and the extra valve coming off the front resavoir . I'm sending a PM . Thanks. Lou
The two letter casting code on factory original MC's is STAMPED on to a machined "half circle" spot on the "nose" of the MC. For most folks, this is a "feature" that really matters when it comes to correct master cylinders. It's the most visible identifier once the MC is installed AND it's commonly partially or completely illegible due to rust/pitting on the machined pad. So....make sure you get GOOD pics showing the stamped code in the nose before you buy one. I may be able to post a pic tomorrow.
Finding a decent original MC cap will also be a challenge IMO.....correct cap not repro'd from what I can tell. Most originals very pitted/corroded. Don't mean to violate any rules here about discussions on people's "For Sale" and "Parts Wanted" ads but the caps can be a big factor as well when it comes to original/correct parts.
