Master cylinder leak on top fittings

D&dgoblin69

Active Member
I had to rewrite this question I had false information by accident. Question has anyone had a leak top master cylinder? I verified it’s coming from base not the screw on fittings. I think this is a master cylinder rubber fitting integral to the master cylinder and the provided base slides into. This area won’t stop leaking?
 

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D&dgoblin69

Active Member
I tried placing a thin washer under master cylinder hose hold down bracket but it was too tight. Essentially what I was up against is the black master cylinder bracket that’s has two gold barns screwed into them had play up and down even with the horse shoe bracket. I took these two screw drivers and pryed outwards till the play went away . I then placed a wood board onto brake pedal to test and no leaks. Also noticed hard brake pedal now!
 

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Rttoys

Goblin Guru
Might need to tweek that bracket, to hold better, or add a small piece of rubber under the bracket to put more pressure on. Anything that will take up space and conform to the curves.
 

D&dgoblin69

Active Member
thanks have you had similar issues at master cylinder leak from top? I need to adjust again ot
Started leaking after my last post .
 

KSLunsfo

Well-Known Member
If memory serves... I think the bracket is a more recent addition. Mine has a worm gear clamp around that black insert, something you could try if that bracket continues to be problematic...
 

Gtstorey

Goblin Guru
I also don't see any thread sealant on the barbed fitting, so it could be leaking there also. I always use thread sealant on Metal to metal threaded fittings. Tapered threads are supposed to seal without out but they often don't. And its hard to tell if the female thread is tapered anyway.

This is low/no pressure so may not be the issue, but I would add some teflon tape if I had it back apart.
 

D&dgoblin69

Active Member
Alright thanks for the ideas I’ll get some thread sealant. Iam used to working on cars where the threads are high pressure and sometimes you gotta keep tight them till they stop. I used a clamp and pushed the black plunger into the master cylinder to keep it tight then tighten bolt I’ll check after I get sealant on the threads.
 

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Rttoys

Goblin Guru
thanks have you had similar issues at master cylinder leak from top? I need to adjust again ot
Started leaking after my last post .
No issues with mine, just figure if you need more pressure there from the clamp, there’s several ways to accomplish it.
 

Rauq

Goblin Guru
Alright thanks for the ideas I’ll get some thread sealant. Iam used to working on cars where the threads are high pressure and sometimes you gotta keep tight them till they stop. I used a clamp and pushed the black plunger into the master cylinder to keep it tight then tighten bolt I’ll check after I get sealant on the threads.
Mine leaked at the threads. I read somewhere that Lonnie used red loctite, so I pulled it, cleaned it, and tried that out. Worked a charm. Obviously make sure the barbs are pointed where you want them.
 

Gtstorey

Goblin Guru
Mine leaked at the threads. I read somewhere that Lonnie used red loctite, so I pulled it, cleaned it, and tried that out. Worked a charm. Obviously make sure the barbs are pointed where you want them.
This is one advantage of teflon tape. It's more forgiving of how tight it has to be and you can, to some extent, stop when it gets pointed where you want it. You don't have to crank it down real tight.
 

D&dgoblin69

Active Member
So I added red locktite 271 cure time 72 hours. Letting it dry over the weekend. After disassembly of leaking brake barb fittings I took pictures . I didn’t realize no matter how hard you tighten barb fittings they will still leak because there not build like a normal bubble flare brake line that gets crushed together as you tighten.the barb fittings housing has no bottom it’s a open hole . There is also hydraulic locktite 455 purple I didn’t have any around. If you look on locktite 271 red it is brake fluid approved .
 

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Sluggonaut

Goblin Guru
I saw the red loctite post before completing that step in my build, so I used it and never had an issue. I also haven't tried to remove the fittings so I don't know if it's an issue during disassembly.
 

Robinjo

Goblin Guru
I saw the red loctite post before completing that step in my build, so I used it and never had an issue. I also haven't tried to remove the fittings so I don't know if it's an issue during disassembly.
I used the red Loctite on mine as well. I haven't had a leak (yet).
 

D&dgoblin69

Active Member
I saw the red loctite post before completing that step in my build, so I used it and never had an issue. I also haven't tried to remove the fittings so I don't know if it's an issue during disassembly.
Sometimes red lock tight will need to be heated with a mini torch or even a lighter for a bit the use a wrench to loosen. Sometimes you can just wrench it loose as well.
 
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