Brake Fluid Resistant Adhesive

[LancerL]

I have a brake fluid leak between reservoir tank and master cylinder due to a tiny gap.

Need advice for a best brake fluid resistant adhesive in the market which dries quickly and can bond plastic and metal.

Disclaimer: This is related to a already discussed and closed previous thread on break fluid leak http://forum.autolanka.com/topic/17434-brake-fluid-refill-interval/#entry287142

Edited December 3, 2015 by LancerL

[luckey007]

You may try with Araldite or with cataloy.

[Davy]

I wouldn't recommend cataloy because the brake fluid will slowly weaken it. Plus, cataloy is meant to be kept moisture-free after application. Not sure about Araldite either because there is no guarantee of how the chemicals will react once it comes into contact with brake fluid.

The best thing to do is to find an o-ring which will seal the gap between the reservoir and the master cylinder. Should be pretty easy to find. Just take the plastic reservoir with you and look for one with the matching size.

A temporary fix would be to apply a few rounds of Teflon tape (referred to as "thread seal" in Sri Lanka). Doesn't react with brake fluid.

[Rohnd]

I have a brake fluid leak between reservoir tank and master cylinder due to a tiny gap.

Need advice for a best brake fluid resistant adhesive in the market which dries quickly and can bond plastic and metal.

Disclaimer: This is related to a already discussed and closed previous thread on break fluid leak http://forum.autolanka.com/topic/17434-brake-fluid-refill-interval/#entry287142

This is not a recommended method on Brakes to apply adhesives. To be repaired in first principles. Replace the Reservoir or Master Cylinder or Any packing or the Whole unit related to this.

[Rumesh88]

Follow Davy's advice above. Adhesives will not hold because eventually it will give way due to vibration. You can get hydraulic grade rubber rings of various sizes from Sp@klit Kadawatha (Opposite entrance to expressway).

[LancerL]

I wouldn't recommend cataloy because the brake fluid will slowly weaken it. Plus, cataloy is meant to be kept moisture-free after application. Not sure about Araldite either because there is no guarantee of how the chemicals will react once it comes into contact with brake fluid.

The best thing to do is to find an o-ring which will seal the gap between the reservoir and the master cylinder. Should be pretty easy to find. Just take the plastic reservoir with you and look for one with the matching size.

A temporary fix would be to apply a few rounds of Teflon tape (referred to as "thread seal" in Sri Lanka). Doesn't react with brake fluid.

Follow Davy's advice above. Adhesives will not hold because eventually it will give way due to vibration. You can get hydraulic grade rubber rings of various sizes from Sp@klit Kadawatha (Opposite entrance to expressway).

Thanks for the input guys.

I doubt the rubber Oring will react with brake fluid and melt off with time? or generally rubber rings are brake fluid resistant?

Also any place to buy Rumesh mentioned type rubber rings in Mount Lavinia, Rathmalana area?

Edited December 4, 2015 by LancerL

[Davy]

Thanks for the input guys.

I doubt the rubber Oring will react with brake fluid and melt off with time? or generally rubber rings are brake fluid resistant?

Also any place to buy Rumesh mentioned type rubber rings in Mount Lavinia, Rathmalana area?

Not all rubber is brake fluid resistant. You should look for one that is specifically designed to be used on hydraulic systems as Rumesh has mentioned above.

[Rumesh88]

Thanks for the input guys.

I doubt the rubber Oring will react with brake fluid and melt off with time? or generally rubber rings are brake fluid resistant?

Also any place to buy Rumesh mentioned type rubber rings in Mount Lavinia, Rathmalana area?

C'mon if you can go to Mt Lavinia why not Kadawatha. I know traffic is terrible at times of the day if you take A1, but if you can reach OCH from Athurugiriya or Weliwita it's less than 10 mins to Kadawatha. The place I mentioned (Sp@rklit) is specialized in hydraulic accessories.

Edited December 4, 2015 by Rumesh88

[LancerL]

Went to garage last weekend and found a leak from the same place.

This time they took it to a Lathe shop and fixed two Teflon bushes on it to fix the gap. Yes that was too tight and no leaks found.

I was so happy and came, but my happiness was temporally.

Yesterday I found that it start leaking again

After spending about 15mins I found the root cause, You remember I told that Master pump replaced sometime back, but the tank was not replaced and used the same one.

Now the issue is that old tank is little lengthy than new Master pump and when Master pump tighten up with two nuts to the booster body, it tension the tank and pulled up little bit, which caused the leak.

As I planned I have three solutions for this.

1. Replace the tank with a new small one with same drain hole gap.

2. Put some washers and extend the gap between booster and Master pump (But brake paddle will go down)

3. Cut the tank to two pieces from Booster side and remove about 2mm plastic layer in between and refit by a good adhesive or something like plastic welding (I'm not sure about the possibility of this)

Please advice the best solution I can workout.

This is a real headache for me now and have spend a lot on this too.

Edited December 8, 2015 by LancerL

[Davy]

I'm going to assume that the "tank" you are referring to here is the master cylinder housing. If so, what you are saying is that you replaced only the pistons and stuff from another master pump which is not identical to the one on the car? Not a good thing to do.

My suggestion would be to just replace the entire master cylinder (this time with the housing as well!) with one that is compatible with your car. You don't want to play Frankenstein with the brakes.

[LancerL]

I'm going to assume that the "tank" you are referring to here is the master cylinder housing. If so, what you are saying is that you replaced only the pistons and stuff from another master pump which is not identical to the one on the car? Not a good thing to do.

My suggestion would be to just replace the entire master cylinder (this time with the housing as well!) with one that is compatible with your car. You don't want to play Frankenstein with the brakes.

No Davy, it is the Fluid tank I was referring. Attached a similar one for better understanding.

Edited December 9, 2015 by LancerL

[Davy]

No Davy, it is the Fluid tank I was referring. Attached a similar one for better understanding.

Can you please share a photo of the exact place that this is leaking from?

[LancerL]

First of all my apology in late posting.

Ultimately I found the root cause of the issue which makes me stressed!

Since the above attempt did not successful, I went to the garage again. This time also they recommend me to replace the nylon “Grommet” (The correct name of it - Found on Internet) with a Teflon made one.

So I went to a lathe work shop again and got it lathed and fixed in to the Master cylinder by them itself. Garage people has put some silicone to seal it and installed the reservoir tank.

After couple of days, again I observed that one of the nylon "Grommet" is leaking.

This time I decided to not to go to the garage anymore and fix this by myself.

I felt that no more Teflon/Nylon “Grommets” will not solve the matter. After Googling a while, found that the ideal/original one will be a rubber made one which resist on Brake fluid.

Ring few spare part shops and everybody said they don’t have it and only comes with the full pump kit.

When I called the Lathe shop, they also didn’t had any Brake Fluid resistant rubber.

So I decided to go to Panchikawatta to fine a used one as I have the old master pump which was removed some time back, which will help me to find the correct size without removing the one fixed at the Car right now.

After visiting couple of recon part shops in “Waththa” beside to the bridge, one shop owner volunteer to remove and give it from one of the old master pump which was hanging on his shop, as everyone else refused to sell only the “Grommet”.

He found the exact size by looking from outside with his experience and the Caliper verified the same measurement.

So I asked him how much he need for this and he quoted Rs. 1,500/- just for two tiny rubber Grommets.

I felt that he is trying to take the advantage out of situation and I told him that this is way too much as it was just Rs. 400/- to lathe the same from Teflon.

Then he jumped down the price to Rs. 1,000/- but my bid was Rs. 700/- and I return back since there were lots of similar shops around and had a feeling that will find one for a reasonable price.

Soon after the next shop I got in has directed me to a brand new spare part shop near Ajan*tha Moto*rs who had the same for just Rs. 150/- each so the total was Rs 300/-. (Check last couple of pictures)

Removed the entire Master pump/tank by myself and fixed new “Grommets” by replacing Teflon made ones. Pushing the tank to the pump was a bit difficult task with new Grommets, but managed to get it done after struggling about 30 minutes.

Sanded the Brake Booster outer cover and around the area against the slight rust due to leaking of Brake fluid and washed with clean water.

After the area completely dry, applied couple of thick coats in black “Metal Primer”.

Covered the area with couple of clothe pieces to protect the new primer from excessive fluid dropping.

Installed pump unit back to the car and fill brake fluid little by little without connecting brake lines to get air out of the compression chamber.

Once fluid start coming out of holes, fixed up the lines and released air by paddling method.

I could not take photos in DIY job as Brake fluid was all around my hands.

It’s more than a month by now and observed no leakages and in perfect condition.

Even though it was a headache in beginning due to less competent garage staff, DIY job has given me a great satisfaction which cannot be valued.

Edited March 12, 2016 by LancerL

[Davy]

Good job! Such a simple thing; can't believe the mechanics actually made a mess out of it.