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Discussion Starter #561
Brake Fluid leak

All

For two years in a row now my brake fluid reservoir has leaked when the weather went from warm to cold. I replaced the rubber gasket last year.. but it appears that the plastic reservoir tip that goes into the master cylinder must be contracting..?

There is no other leak anywhere, and during the warm months.. not a drop..

I have a detached garage so it gets pretty cold...

Any ideas??

Thanks
 

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I think the plastic little elbow 90 has a hairline crack or
The Resevoir tip is cracked. Replace the plastic parts
That's my opinion
 

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Can Opeler
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If you have the OGTS master cylinder then you need to replace the two rubber seals again. Every OGTS master cylinder I have does this. Take a paper towel and clean off the brake fluid and see how it leaks. Mine all leak around the outside of the rubber seals not in the inside around the plastic inlets.


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Discussion Starter #564
If you have the OGTS master cylinder then you need to replace the two rubber seals again. Every OGTS master cylinder I have does this. Take a paper towel and clean off the brake fluid and see how it leaks. Mine all leak around the outside of the rubber seals not in the inside around the plastic inlets.


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I do have an OGTS MC, but replaced the gasket last year..... very frustrating... the oil has ruined the regular oil drips .. lol :haha:

Does yours leak in the summer or just when it gets cold? thanks
 

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Can Opeler
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I do have an OGTS MC, but replaced the gasket last year..... very frustrating... the oil has ruined the regular oil drips .. lol :haha:

Does yours leak in the summer or just when it gets cold? thanks
My orange GT leaks constantly. It will drain its reservoir in a week. My red GT is a lot slower and needs to be topped up every month or so. I haven’t noticed changes due to weather, but it might. The drips have ruined my paint in the belly pan too. I was actually going to order some new seals today.


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If you have the OGTS master cylinder then you need to replace the two rubber seals again. Every OGTS master cylinder I have does this. Take a paper towel and clean off the brake fluid and see how it leaks. Mine all leak around the outside of the rubber seals not in the inside around the plastic inlets.


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Are you talking about the 22mm master? I am waiting for one to come off backorder, so I am not pleased to hear of this problem.
 

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Can Opeler
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Are you talking about the 22mm master? I am waiting for one to come off backorder, so I am not pleased to hear of this problem.
I’ve never heard of anyone else having this problem, so maybe I just got a defective seal set although both of my GTs leak here and they have brand new everything. Wait and see if others chime in with leaks. The OGTS brake booster and master cylinder kit is really really good otherwise.


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Our new MC leaked as well (after about ~2 years).

It was leaking from around the edge of the outside of the front seal, and it had even formed a little bit of rust on the metal under the seal (see photos in attachment, there is a circle of brake fluid around the rubber seal).

I removed the reservoir and both seals, then cleaned them up really well.

To fix the problem, I very carefully put a light coat of Seal-All to cover the exposed metal surface around the top of each hole and around the underside of the top of the seal. I had attempted to google for a sealant which would be brake fluid resistant and I had found some references to Seal-All (I googled again just now and couldn't find a solid reference for certainty). If anyone has a recommendation for a better sealant, please offer it up. In theory, no brake fluid should come into contact with the Seal-All unless it passes the first ring of rubber, so this approach should not contaminate the system.

In short, I just "glued in" the larger top of the seal, so that it assists the lower part of the seal to keep the brake fluid from leaking through (it has nowhere to go). This approach solved my problem (brake fluid hasn't dropped whatsoever in ~6+ months).

Brakes have otherwise been GREAT! This solution solved our one and only problem. I think tighter rubber seals would work best. I appreciated the way my approach also covered up the exposed metal under the rubber seal (which had started to rust a little due to the ongoing slow leak which had formed). Removing these seals will now be a bit of a problem.

I hope this helps. If this was the wrong way to solve this problem, let me know (so others don't copy it).
 

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Can Opeler
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Our new MC leaked as well (after about ~2 years).

It was leaking from around the edge of the outside of the front seal, and it had even formed a little bit of rust on the metal under the seal (see photos in attachment, there is a circle of brake fluid around the rubber seal).

I removed the reservoir and both seals, then cleaned them up really well.

To fix the problem, I very carefully put a light coat of Seal-All to cover the exposed metal surface around the top of each hole and around the underside of the top of the seal. I had attempted to google for a sealant which would be brake fluid resistant and I had found some references to Seal-All (I googled again just now and couldn't find a solid reference for certainty). If anyone has a recommendation for a better sealant, please offer it up. In theory, no brake fluid should come into contact with the Seal-All unless it passes the first ring of rubber, so this approach should not contaminate the system.

In short, I just "glued in" the larger top of the seal, so that it assists the lower part of the seal to keep the brake fluid from leaking through (it has nowhere to go). This approach solved my problem (brake fluid hasn't dropped whatsoever in ~6+ months).

Brakes have otherwise been GREAT! This solution solved our one and only problem. I think tighter rubber seals would work best. I appreciated the way my approach also covered up the exposed metal under the rubber seal (which had started to rust a little due to the ongoing slow leak which had formed). Removing these seals will now be a bit of a problem.

I hope this helps. If this was the wrong way to solve this problem, let me know (so others don't copy it).
I don’t even have to post my pics. Yours look EXACTLY like both of mine including the rust. I’ll give some hydraulic sealant a try on mine. Hydraulic sealant has no particles so it doesn’t contaminate a system. I don’t know about seal all, but i bet you’ll be fine. Thanks for posting.


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Discussion Starter #571
I have to look at some of the ideas too.. Thanks for helping me with all this guys! I was getting really bummed that I did something wrong when I switched the gaskets last year.

Again, this is only a cold weather issue .. so I'm still curious as to if it's the rubber or plastic that is contracting
 

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I have to look at some of the ideas too.. Thanks for helping me with all this guys! I was getting really bummed that I did something wrong when I switched the gaskets last year.

Again, this is only a cold weather issue .. so I'm still curious as to if it's the rubber or plastic that is contracting
The coefficient of thermal expansion for rubber is way, way less than for any type of plastic. So as the temperature drops the plastic shrinks more than the rubber.
 

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The coefficient of thermal expansion for rubber is way, way less than for any type of plastic. So as the temperature drops the plastic shrinks more than the rubber.
Which is why we use clamps on rubber hoses with plastic connectors, etc! You do have clamps on those barbed connectors don't you? :sigh: .... :ugh: ... :yup:

Just thinking out loud! -- Doug

PS - Have you started building the new top for The Murph?
 

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Discussion Starter #574
Which is why we use clamps on rubber hoses with plastic connectors, etc! You do have clamps on those barbed connectors don't you? :sigh: .... :ugh: ... :yup:

Just thinking out loud! -- Doug

PS - Have you started building the new top for The Murph?


Hey

I have a totally stock set up... no clamps (yet!) ... I am defin. gonna try that idea... please send me a pic of what it should look like at the end.

This spring I plan on tackling the roof again.. This past year had lots of turns in it and I just couldn't focus on Murph... trying to slowly wake up from a fog! Hope your well..
 

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Before solving the problem, make sure you have root cause!

No clamps would have solved the problem I had (and likely Kyler).

Take a rag or shop towel and clean up the area to make sure everything is super dry.
Revisit in a few hours, or the next day, to catch the leaking as soon as it occurs, so that you can detect where it is coming from.
My leak was between metal/rubber.

I live in Canada. It is 16 F ( -9 C) this morning. I have no leaks between any rubber/plastic.

Good luck!
 

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Can Opeler
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Charles, Your post #200 here has lost it's photos! If you still have them can I request you make a separate thread about your tie down strap method in the suspension forum. Over the last few years I have sent about 40 people to this thread for this method, but the link I send is useless now that the pics disappeared.
 
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