Master Cylinder for Chev on eBay
 

Tha listing is for a "NOS" Delco master cylinder. The photos show it to have part number 5450261 cast into the body, the parts book for the C15A shows the master cylinder as 5450260. It is clearly marked in the casting as 1-1/4" diameter and has bottom mount studs.
http://cgi.ebay.com/ebaymotors/ws/eB...1123&viewitem=
I know nothing about the seller, other than I've seen other auctions. I'm not sure the photos completely support the NOS statement, but it seems in good shape externally.

Thanks for the heads up. Copying for future reference:

I bought it for the C8. Mine had some deep rust pits and the machinists wanted more than that to fix it. I had considered filling the pits with JB weld and honing it but now that can wait for the next truck.

Hold on to you old one
 

Hi Dave

Hold on to your old master cylinder, I've had three of them sleeved which is probably the end answer. I know I sound like a broken record about sleeving brake cylinders but it is the only answer I've found that last over the long haul. When I first restored my HUP in 1978 I searched all over and eventually found 4 NOS wheel cylinders and even a NOS master cylinder, replaced all the rubber parts with modern newly manufactured bits. The NOS stuff lasted about 5-7 years before it started to leak and the bores showed signs of pitting. Then sent the original cylinders (I saved them) out and had them all sleeved in brass. Those cylinders are still on the HUP the rubber parts seem to last 7-10 years before something will leak at which point I replace all the rubber parts including the rubber brake lines.


Cheers Phil

They were using brass here in the 1970's. ( a large brake company called BRELCO ) But with the aluminium alloy pistons used in some applications, weird electrolosis type stuff had them behaving oddly. They went over to stainless steel because of the problem. I had my MB Jeep cyls done in brass ..the machinist drilled through the bleed screw hole on a rear cyl. too much and into the opposite wall . It let go as I was coming down a steep driveway ..no brakes . I could have sued the idiots who did it .
Mike

Thats a new way to bleed the brakes
 

Hi Mike

Did you make the turn at the bottom of the driveway or go up on the neighbors lawn.

You are right about the issues with brass and aluminum pistons the company that I've used to sleeve all my cylinders over the years was aware of the issue when I asked, response I got was that they are very particular about the actual alloy mix of there brass and also with its purity.

So far so good I've had no problems with pistons sticking or corrosion.

Phil,

Like you ,I had no problem with sticking pistons , and the Jeep was laid up for long periods too, but never had any problems. The episode with the brakes: I managed to stop by steering sideways into the high stone side wall beside the driveway. It was rather steep but I scraped along the wall and it just managed to stop the Jeep - damaging the rear corner panels in the process. The scary thing was, at driveways end, there was a 8 feet drop into a rock garden.The hole in the cylinder was tiny , the size of a pin head, but it was still enough to lose all pressure in the system. A friend attempted to repair the cyl., he silver soldered the hole over , but that cyl. was never useable again, the heat distorted the brass somehow and the piston wouldn't fit back in.
Mike