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| | | | Joined: Jan 2002 Posts: 25 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2002 Posts: 25 | I hoping that someone here can help to keep me safe. I have a 62 Chevy c-80 that had a leaking master cylinder. I also have a 60 Chevy c-20 that I broke one of the rear trailing arms on. I have since swapped the master cylinders, but haven't attempted to drive the big truck yet. Will the smaller bore sizes from the c-20 have a negative effect on the braking (and clutch) performance of this truck?
Thanks,
Kael | | | | | Joined: Sep 2004 Posts: 235 Shop Shark | | Shop Shark Joined: Sep 2004 Posts: 235 | How much smaller is the C-20 master? If there is a big difference, you are better off getting a new master or rebuilding the one you have. If it is a small difference you should be able to drive it. When the truck has a load on it is when you will have problems. | | | | | Joined: Jan 2006 Posts: 586 Shop Shark | | Shop Shark Joined: Jan 2006 Posts: 586 | Personally,I wouldn't take the chance.There is a big difference in curb weight between the 3/4 ton C-20 and the C-80.Maybe you can get away with it in Wisconsin,but I am in New York where most folks drive funny.
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Must be able to cook , clean , sew , tune engines and polish trucks. Must have old Stovebolt and garage. Please send picture of old Stovebolt and garage.
| | | | | Joined: Feb 2000 Posts: 587 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 587 | If master is too small, you won't be able to get solid pedal or none, even tho all is bled good. Even smaller amounts like 1/8" make a big diff. I didn't believe it, and tried it, never did have good brakes, till I got correct size Master. 80 series is a Big rig, close to 1-1/2" bore I bet, and 20 series only has about 1". Am I correct? The clutch sides are usually 15/16", and may stay the same on those.
It's about "Volume" needed to run all the brakes, not just Pressure.
G.L. Grumpy's
Old Iron Ranch
Huntington, IN 46750
MM R tractor, Speedex
and Power King tractors
| | | | | Joined: Jan 2002 Posts: 25 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2002 Posts: 25 | Thanks,
That is what I expected to hear. I don't remember the bore sizes right now although there is a difference of about 1/8". The biggest reason that I swapped it out originally is that I was quoted a price between $425 & $780 for a new replacement of the one that was on my truck when I got it. I later found out that the one on it was not the original one anyway. I am still looking at finding a reasonably priced replacement. Until then, the truck stays parked.
Kael | | | | | Joined: Sep 2004 Posts: 235 Shop Shark | | Shop Shark Joined: Sep 2004 Posts: 235 | Maybe you can find a company that can rebuild the master for you. Might be cheaper than buying new | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Put kits in it. It,s easy to do. Get a brake cyl. hone. If it has pits that wont come out you can get them sleeved.
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 2006 Posts: 483 Shop Shark | | Shop Shark Joined: Mar 2006 Posts: 483 | Where can you get the proper rebuild kits for the 61 11/2 ton clutch/brake master cylinder? I got one from O'Relliey and it's the wrong one listed in there book.Both units bleed off. | | |
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