Author Topic: Secondary piston-master cylinder  (Read 1835 times)

stovebolt

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Secondary piston-master cylinder
« on: June 02, 2016, 04:38:28 PM »
I'm reluctant to reuse this secondary piston on my master cylinder rebuild because of the pitting shown in the photo. I'd appreciate any help in finding a GM NOS piston. It's for the Delco Moraine master cylinder, GM part number is 5452694 Group 4.653. Thanks, Joe.
« Last Edit: June 02, 2016, 06:34:09 PM by stovebolt »

Kelley W King

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Re: Secondary piston-master cylinder
« Reply #1 on: June 02, 2016, 05:43:42 PM »
You might want call White Post Restorations. If fact if you let them rebuilt they guarantee for night. They did my corvette many years ago. After about 10 years it started leaking. They were surprised when I said I still had the receipt, they redid it for free.
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stovebolt

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Re: Secondary piston-master cylinder
« Reply #2 on: June 02, 2016, 06:43:21 PM »
Thanks for the reply. I recently had the master cylinder sleeved and I've got a GM rebuild kit which doesn't include the secondary piston.

rich69rs

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Re: Secondary piston-master cylinder
« Reply #3 on: June 02, 2016, 08:47:46 PM »
Back in Nov 2009 I rebuilt my master cylinder.  Got the rebuild kit from NAPA - don't recall whether or not it included the secondary piston.  Cost for the rebuild kit was $33.19 plus tax.  All has worked just fine since after cleaning everything and using the parts from the rebuild kit.  I didn't have to sleeve my master cylinder - good to go with a little honing.
Richard Thomas
1969 RS

69Z28-RS

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Re: Secondary piston-master cylinder
« Reply #4 on: June 02, 2016, 09:39:17 PM »
Just curious who did the sleeving if they didn't include the rebuild kit parts??  and what was it sleeved with?  Stainless or brass??
I also had problems finding the complete kits for my '69 MC (disk brake) and was one of the reasons I sent the MC to White post for rebuilding as they have the parts if they do the rebuild; they sleeve in brass only.  I don't believe they sell the rebuild kits outright and separately...
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
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stovebolt

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Re: Secondary piston-master cylinder
« Reply #5 on: June 02, 2016, 09:57:20 PM »
Apple Hydraulics did the sleeving in brass. They offer a complete rebuild or sleeving only, which I opted for.

69Z28-RS

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Re: Secondary piston-master cylinder
« Reply #6 on: June 02, 2016, 10:14:35 PM »
Perhaps Apple will sell you the rebuild kit, if you tell them you had them sleeve it...   if not, an option should exist for paying them to 'complete the rebuild'..?
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe, '70 Mach I 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

JKZ27

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Re: Secondary piston-master cylinder
« Reply #7 on: June 03, 2016, 10:23:50 AM »
I think I ran into this problem years ago when I found my MC piston pitted. I ended up just buying a rebuilt master cylinder and removed the parts I needed from it.
John
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stovebolt

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Re: Secondary piston-master cylinder
« Reply #8 on: June 04, 2016, 12:14:34 PM »
These are all very good alternatives. I do have a NOS GM rebuild kit with everything but the secondary piston. There has to be some out there, they were used on many GM cars from'67 to '72 with four wheel drum brakes. Secondary piston P/N 5452694.

Stingr69

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Re: Secondary piston-master cylinder
« Reply #9 on: June 05, 2016, 06:08:53 AM »
Did the Apple Hydraulics sleeve on my original master cylinder and couldn't be more pleased. Bought a remanufactured master cylinder and scavenged it for the secondary piston. Couldn't find that secondary piston available any other way.  Easy and not expensive.

stovebolt

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Re: Secondary piston-master cylinder
« Reply #10 on: June 05, 2016, 11:21:19 PM »
If I don't find the piston pretty soon, I'll have to go the cannabilization route. Thanks for all your input.