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Discussion Starter · #1 ·
Will Brake Fuild Eat Thru Black RTV Sealant? I have some brakefuild seeping thru the o-rings at the Res. and Master Cylinder. Just for safety measures, I'm going to rub sealant around it until Monday when I get to work and Find out what Would be easist way to fix it right. It looks like its been leaking for a while, But nothing has been on the ground.

Thanks Guys And Gals!
Rick
 

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I don't think it will, but don't leave it like that any longer than you have to. make sure to spray where you are going to put the silicone down with brake cleaner to take the grease and oil off, othrwise it won't do any good.
 

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Discussion Starter · #3 ·
I went out there and check the situation out more. It will only leak when you wiggle the res. I can pump on the brakes over and over again and it wont leak a drop. I'm going to put the RTV on it and see what happens. I'll most likey have to replace the Master cylinder.

Rick
 

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On 2003-02-01 22:34, moparman71 wrote:
brake fluid will eat right through that stuff. plus, you do not want any of that residue getting in your brake system and contaminating your fluid!

yeah, mine did the exact same thing.... when i would try to take the cover off, the resivour would tilt, and leak out of the bottom. just don't tilt it, or get yourself a new master cylander and do it right.
 

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I just changed out my master cylinder and when I put put one of the lines in it didn't seat in that good and I had fluid coming out of my threads and someone told me to go to home depot and get some thread sealer. You can find it in the plumbing section its in a little white tube and it resists any thing. The guy that told me this uses it on threads when he is installing piping for oil furnaces in houses. So I tried it and it stopped the leak and it hasen't deteriorated yet but I'll keep watch of it and see.
 

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Ok, first thing....every single one our our master cylinders will leak right there! It is a given fact! I was worried too, especially when I went to Beast's place last fall. We did work on my brakes and it leaked worse than it ever had cuz we were all over the brakes. Well, after we were done, we filled it up and since then it hasn't lost a single drop. When you rock it back and forth, it works the fluid down. If you leave it, it won't leak anything. But when you play with it...it will. The solution is to not play with it and when you have to replace fluid, just don't worry about it when you take the lid off and rock it! :bigthumb:


And second thing....DON'T PUT ANY THREAD SEALER ON THE THREADS OF BRAKLINE STUFF!

Thread sealer is meant for pneumatic lines (air tools) and other stuff like that. If you think brake fluid will eat through paint and RTV...guess what it will do to that whimpy, thin white tape! Now the loctite type sealer you mentioned might hold up better.....but still, possbile contamination can occur like with the RTV idea.
Brakeline fittings are "compression fittings" meaning that they are made of a soft metal (brass and/or copper depending on washers etc.) These compression fittings are meant to be torqqued down really tight so that the soft metal molds, squishes, and conforms so that it completely seals off the liquid trying to be contained. The reason for this is as previously mentioned....brake fluid is a hydraulic fluid and will eat through everything but most metals. That is why you have a copper washer on your caliper where the brakeline/banjo nut screws into the caliper. That copper washer compresses and will not allow any fluid to leak past.

If I were you, I would go back and take that thread sealer off....cuz it will get eaten at and eventually allow leakage. Just screw the fittings on super duper tight and it won't leak. :cool::
 

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:withstupid:

On 2003-02-02 08:02, Blackdog wrote:
I just changed out my master cylinder and when I put put one of the lines in it didn't seat in that good and I had fluid coming out of my threads and someone told me to go to home depot and get some thread sealer. You can find it in the plumbing section its in a little white tube and it resists any thing. The guy that told me this uses it on threads when he is installing piping for oil furnaces in houses. So I tried it and it stopped the leak and it hasen't deteriorated yet but I'll keep watch of it and see.

my fittings are tapered a little, so if you don't tighten them down, they will be loose.
 

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Discussion Starter · #12 ·
Alright, I won't use RTV or anything, I just went playing with it again, Cleaned it ALL off, pulled the cap off, repositioned the rubber(when I snapped the cap off I noticed my fingers were covered in fuild) and started the trucks, playing with the brakes looked at it, still dry as a bone. Could that top rubber peice been screwed up? I did go up steep hills and such yesterday which may have caused it to leak...

Rick
 

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I have the darn lines as tight as they can get inside the master cylinder but I don't want to go any tighter cause it is aluminum and I don't feel like being out another $106 cause I stripped it out. Granted the thread sealer does look gubbered on there and (by the way it isn't plumbers tape) but that was the only option I had for the moment and it has worked so far but I am open for suggestions.
 

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Ok, first thing....every single one our our master cylinders will leak right there! It is a given fact! I was worried too, especially when I went to Beast's place last fall. We did work on my brakes and it leaked worse than it ever had cuz we were all over the brakes. Well, after we were done, we filled it up and since then it hasn't lost a single drop. When you rock it back and forth, it works the fluid down. If you leave it, it won't leak anything. But when you play with it...it will. The solution is to not play with it and when you have to replace fluid, just don't worry about it when you take the lid off and rock it! :bigthumb:



And second thing....DON'T PUT ANY THREAD SEALER ON THE THREADS OF BRAKLINE STUFF!


Thread sealer is meant for pneumatic lines (air tools) and other stuff like that. If you think brake fluid will eat through paint and RTV...guess what it will do to that whimpy, thin white tape! Now the loctite type sealer you mentioned might hold up better.....but still, possbile contamination can occur like with the RTV idea.

Brakeline fittings are "compression fittings" meaning that they are made of a soft metal (brass and/or copper depending on washers etc.) These compression fittings are meant to be torqqued down really tight so that the soft metal molds, squishes, and conforms so that it completely seals off the liquid trying to be contained. The reason for this is as previously mentioned....brake fluid is a hydraulic fluid and will eat through everything but most metals. That is why you have a copper washer on your caliper where the brakeline/banjo nut screws into the caliper. That copper washer compresses and will not allow any fluid to leak past.


If I were you, I would go back and take that thread sealer off....cuz it will get eaten at and eventually allow leakage. Just screw the fittings on super duper tight and it won't leak. :cool::
What about bleeder screws leaking air in under vaccum during bleeding process? What can I use to stop that while I do my bleeding and then tighten the screw when I'm done? I'm so glad I saw this cause I just bought a tube of clear silicone RTV but what you said about break fluid eating it up makes total sense.
 
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