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| | | | Joined: Aug 2005 Posts: 341 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 341 | Does anyone know of a vendor source for the large washer that goes between the junction block and the back of the master cylinder? '53 3100. Here's a past explanation from Denny: If I may, I'll repeat myself Rich. "If either surface has a scratch or if they are not parallel you probably won't stop it from seeping".
Over the past quarter of a century at my last job I did a lot of leak detection on cryogenic and vacuum systems. Metal seals are the norm because of the extreme cold. Make sure that you are using a good, new, annealed, unscratched copper gasket and that the sealing surfaces are in good condition. And once again, that large of sealing surface will take a lot of torque to seal. But use some common sense, you can still pull those fine threads out if you over do it. Getting a bigger hammer is not the answer here, getting a good seal and sealing surface is!
One last thought, you probably will not find a more solid platform to tighten the nut in than when the MC is bolted to the frame. I wouldn't do it in the vise.
Ain't brake systems a pain in the Arss!!!
Denny Graham
Sandwich, IL
Allan
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1951 GMC 1/2-ton
Two 1953 Chevy 3100 5-window
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | It comes with a master cyl. kit.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy magfarm51, I couldn't find the washer separately, but it is part of the overhaul kit. Raybestos p/n MK146 $14.76 at RockAuto, hope that helps, | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | I've found them in an assorted copper washer box NAPA had on the shelf
Bill | | | | | Joined: Aug 2005 Posts: 341 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 341 | Thanks for the tip on the kit guys. Hey Bill, can you find me another one of those boxes?  Actually, after looking at the kit that's not it. The washer I'm referring to seals the junction block to the back of the MC fitting. I believe it should be copper.
Last edited by magfarm51; 01/27/2012 10:57 PM.
Allan
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1951 GMC 1/2-ton
Two 1953 Chevy 3100 5-window
| | | | | Joined: Jun 2006 Posts: 693 'Bolter | | 'Bolter Joined: Jun 2006 Posts: 693 | when i did over my brakes, i brought the old one to NAPA and they visually matched it. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | I'm not talking about a box of washers you buy, but a box the store has in the stock room with a wide selection of sizes they can select your requirements from, as Tom says - they are copper and they have slight grooves on them
Bill | | | | | Joined: Apr 2010 Posts: 160 'Bolter | | 'Bolter Joined: Apr 2010 Posts: 160 | You guys are talking apples and oranges. Some of you are talking about the large washer that goes on the nut that screws in the M cyl. I beleive the poster is talking about a smaller washer that seals the fitting that screws into this nut. Often called a "banjo"fitting. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | no they're all cherries  in the same box of assorted copper washers at NAPA, pick the required size Bill | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | The Help line of parts has a small assortment of those copper washers in a package. They are available at most parts stores.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I believe on the 1/2 ton, there is a fitting on the MC that connects to two lines, unlike the 3/4 ton. | | | | | Joined: Aug 2005 Posts: 341 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 341 | That's correct Fred.
I'll take mine down to our NAPA store and see if they have a selection. Thanks!
Allan
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1951 GMC 1/2-ton
Two 1953 Chevy 3100 5-window
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I see in the factory assembly manual for that assembly, they list the connector fitting, a bolt and two gsakets.
Fred | | |
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