69 PB Master Cylinder

[Douglas C.]

Re: 69 PB Master Cylinder

John------


1969 Chevelle with disc brakes. As far as I can tell, this was the only application for the "BA"-coded master cylinder.

However, I believe the 5468309 casting was also used for some 68-76 Corvette with power brake applications.

As also a Chevelle guy over the years I can tell you for some reason the BA code one is hard to find these days. I'll put mine on e-bay and ask around $300.

Thanks, Doug

[Joe L.]

Re: 69 PB Master Cylinder

As also a Chevelle guy over the years I can tell you for some reason the BA code one is hard to find these days. I'll put mine on e-bay and ask around $300.

Thanks, Doug

Doug-----


I'm not surprised. It was used only for 1969 Chevelles and then only for those with disc brakes. However, there were over 110,000 of those built. Most likely, though, the vast majority of those master cylinders have either been scrapped by now or are circulating in the world of commercially rebuilt master cylinders. In the latter case, they may have been re-configured for other applications and, thus, will never find a "proper home".

[John H.]

Re: 69 PB Master Cylinder

John-----


Is the "BA" cylinder dated?

Joe -

There are no tiny Julian stampings on either of the outlet port spotfaces, but there's a "185" Julian casting date above and rearward of the front outlet boss, and the Danville "D" below that.

[Joe L.]

Re: 69 PB Master Cylinder

Joe -

There are no tiny Julian stampings on either of the outlet port spotfaces, but there's a "185" Julian casting date above and rearward of the front outlet boss, and the Danville "D" below that.

John------


I can't figure out why some of these master cylinders have the date stampings and some do not. Since the "185", if it represents a date at all, probably only represents a consecutive day of the year, we don't know if the year is 1968 or 1969. My master cylinder is stamp-dated mid 1969 so, at about that time, they were stamping master cylinders. It might be that in mid-1968 they were not stamping.

[Terry M.]

Re: 69 PB Master Cylinder

John------


I can't figure out why some of these master cylinders have the date stampings and some do not. Since the "185", if it represents a date at all, probably only represents a consecutive day of the year, we don't know if the year is 1968 or 1969. My master cylinder is stamp-dated mid 1969 so, at about that time, they were stamping master cylinders. It might be that in mid-1968 they were not stamping.

If you ever figure out why some are stamp dated and some not and some are stamped with characters that are clearly not dates, let us all know. Most of the master cylinders I have seen have what appears to be some sort of casting date, but in most cases (Admittedly I have seen more Corvette master cylinders than other models) it appears to not be a complete date as John H has reported. We pretty much have concluded, I think, that small block exhaust manifolds do not have a complete casting date, but most (at least in the early C3 era) have the Julian date cast into them without a year. Master cylinders are a whole different kettle of fish. When I get back from Altoona I will attempt to lay out my stash of master cylinders and see if there is any additional information to be gleaned from them -- assUming I am not able to return to work.

[John H.]

Re: 69 PB Master Cylinder

If you ever figure out why some are stamp dated and some not and some are stamped with characters that are clearly not dates, let us all know. Most of the master cylinders I have seen have what appears to be some sort of casting date, but in most cases (Admittedly I have seen more Corvette master cylinders than other models) it appears to not be a complete date as John H has reported. We pretty much have concluded, I think, that small block exhaust manifolds do not have a complete casting date, but most (at least in the early C3 era) have the Julian date cast into them without a year. Master cylinders are a whole different kettle of fish. When I get back from Altoona I will attempt to lay out my stash of master cylinders and see if there is any additional information to be gleaned from them -- assUming I am not able to return to work.

Terry -

My '69 Z/28 also uses the "309" master cylinder (stamped "US" on the front pad), and it has a "45" Julian casting date on the outboard side (February 14th); the car was built on February 27th. It does not have any tiny Julian date stamps on the outlet spotfaces either.

[Terry M.]

Re: 69 PB Master Cylinder

Unfortunately my 1967 Chevelle original master cylinder has gone down the road (I think, but I will check) -- I now have 4-wheel disks. I wonder if Corvette was the only car that got (sometimes) date codes on the master cylinder. I have no proof or even good suspicion of that. Just musing out loud. I think there is a lot more to be learned about this.