Thanks to Tom (Tom406) and Rick (SS427) and the "Pay It Forward" classified section, I have a nice, date code correct 5470409 Delco dual bleeder, master cylinder that just happened to come off of another 1972 Firebird. [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]
https://www.yenko.net/ubbthreads/ubbt...der#Post531958
I took it apart and tried honing it myself but the bore was a bit too pitted. I ended up sending it to Whitepost Restorations to have it sleeved. It was $175. It took about a week. I got it yesterday and I installed it today.
It was not an uneventful day. [img]<<GRAEMLIN_URL>>/rolleyes.gif[/img]
They say timing is everything. When I took the repro dual bleeder master cylinder off I noticed that the rear reservoir was rather low. Very strange since not a lot leaked out when I removed it. I didn't think much of it at the time. I then bench-bled the new master cylinder and installed it. I then bled all the brakes. Twice, starting at the farthest rear cylinder. I had the car on jack stands so I could get to everything and eventually do a running test.
I started the car to check the brakes with the wheels spinning. I put it in gear. I then stepped on the brakes and the rear wheels kept spinning - no braking at all. Very strange since I just bled the brakes and I thought I bled them enough. The front brakes were holding tight but the rears were not doing much of anything. I bled the rears again and then they worked properly...for a few minutes.
I went and refilled the master cylinder and then tested the brakes again...no rear brakes. Really, very strange now. I thought maybe it was the combination/metering valve had activated but the pin was in the correct neutral position.
So I pulled the rear wheels and the drums and saw that the driver's side rear wheel cylinder had just started leaking inside the drum. Great timing for a complete part failure! Luckily the autoparts store was open and had a pair of rear wheel, brake cylinders in stock so I threw them on and everything works fine now.
Thanks again, Tom and Rick. [img]<<GRAEMLIN_URL>>/beers.gif[/img] I owe you a frosty, cold mug of DOT 3.