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| | | | Joined: Apr 2013 Posts: 144 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2013 Posts: 144 | trying to address frozen brake pedal (literally cannot push it down) found the cap to the master cylinder size to not match any of my standard sockets. What is the master cylinder lid or fill cover "trick" that I'm not aware of? looks like it'd be hard to get to under floorpan with an adjustable wrench and none of my sockets fit on it through the inspection floorpan hole. Its not rounded or anything, it looks very solid, but what size is it??? THANK YOU. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | not sure on the size, but if you put an adjustable wrench on it straight up and down, then use another wrench to turn the first, you can usually get them off - very possible you won't get it off tho, the originals do seize on good, the 'trick' is to replace it with a repro plastic or aluminum one and use a rubber O-ring under it
Bill | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | A 6 point 7/8 in. socket should get it off if it is hex. If it is square it will take a 1/2 in 8 point socket.
Sounds like you have more problems then getting the cap off. If the pedal shaft is stuck you can remove the plug in front of the cyl. & put a grease fitting in it. Then shoot it with some grease. If the piston in the cyl. is froze you will have to pull the cyl. & replace or rebuild it.
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: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Some of the square headed caps may also be 3/4" square.
Bill Burmeister
| | | | | Joined: Apr 2013 Posts: 144 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2013 Posts: 144 | likely I'll have to replace whole thing, I can't even kick the hell out of it and get the brake pedal to move thanks everyone. I tried all my standard SAE sockets but no fit, plus the cap is frozen on. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | the frozen pedal could be the pivots - not much point in fighting the cap in place when you know you have to pull the MC and at least put a kit in it, much easier to get the cap off on the bench
Bill | | | | | Joined: Apr 2013 Posts: 144 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2013 Posts: 144 | I'm following up in case anyone runs a search in the future, the cap size hex is 7/8, don't know why it took me about 5 different sockets to get one that'd work. | | | | | Joined: Feb 2007 Posts: 434 Shop Shark | | Shop Shark Joined: Feb 2007 Posts: 434 |
R-Bo
1959 Apache 1/2 ton Big Window, Short bed Fleetside (under reconstruction)
1966 GMC 305V6 in the family
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