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Discussion Topic:
Master leaks
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Pauls39 |
10-11-2013 @ 10:34 PM
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Member
Posts: 81
Joined: Oct 2009
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Several members have had problems with master cyls made in the "land of almost right". The main problem seems to leaks where the brakelight switch screws into the casting. New washers, anealed new washers, etc have been tried, still a small seepage will appear. They are using DOT3 fluid so that does not seem to be part of the problem. We are wondering if the casting is milled square to the threaded hole? Or are the castings just junk?
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supereal |
10-12-2013 @ 9:17 AM
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Senior
Posts: 6819
Joined: Oct 2009
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I think you answered your own question. Bad castings seem to be the rule today. I suspect the threads are bad or incorrect. If it is new, return it. The master cylinder is the most important part of the brake system.
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TomO |
10-13-2013 @ 7:17 PM
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Senior
Posts: 7253
Joined: Oct 2009
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They don't know what a standard thread is. They use something in between a metric and standard, so neither will work.
Tom
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WKnighter |
10-13-2013 @ 7:36 PM
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Member
Posts: 8
Joined: Jun 2012
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I would think that the brake switch has pipe threads and a couple wraps of teflon tape would stop the leak. Larry
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39topless |
10-14-2013 @ 6:29 PM
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Member
Posts: 77
Joined: Feb 2013
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I've tried plumbers tape on a master and, of course, the brake fluid just eats it up in seconds. You really need good quality compression washers and well machined threads. Good luck with that. I suggest trying to maintain an original.
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supereal |
10-14-2013 @ 9:23 PM
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Senior
Posts: 6819
Joined: Oct 2009
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We have had some success using Teflon washers to stop fluid leakage. The type that are about an eighth inch thick work best. If the threads are not good enough to allow the switch to be fully tightened, I wouldn't try to use the cylinder, in any case.
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TomO |
10-15-2013 @ 7:12 AM
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Senior
Posts: 7253
Joined: Oct 2009
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Wagner re-manufactures master cylinders in the US and Raybestos makes some of its products in the US. Both have quality control procedures that ensure that their products will work when installed. The P/N for the master cylinder is MC 1050 and is available online at Amazon and Rock Auto as well as your local parts house.
Tom
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Pauls39 |
10-15-2013 @ 8:26 AM
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Member
Posts: 81
Joined: Oct 2009
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Thanks Super. I'll tell the guys to try the teflon washers. Often the masters are missing or beyond hope of being rebuilt. After 70+ years they have been redone too many times. In the future they will look for the American made parts as Tom O suggested. Thanks to all.
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