Leaking Brakes Fluid Reservoir - Is There A Way To Seal it?

[Pawel66]

A bit of a mishap this morning - I looked briefly under bonnet before going for a ride and spotted leaking brake fluid reservoir. From the recently discussed third nipple!

Can anyone recommend a way to seal it?

It is the Authentic Classic one that leaked. I would like to keep it and use it as it has perfect shape and color.

I installed for now the original one (with Authentic Classic one internals). It went a bit through whitening treatment, but not successfully, as you see.

Is there a way to seal the Authentic Classic one?

[wwheeler]

Because the material is plastic, that nipple would be sealed by heating and crimping. The heat will melt the plastic and cause it to fuse together. The crimp obviously closes the section and creates the seal. This is a similar operation to heat sealing plastic bags except much thicker.

Problem now is that brake fluid has contaminated the fusing area. I am not sure the plastic will fuse given the contamination. You MIGHT find an adhesive that will stick to this plastic, but won’t be easy. And again the brake fluid has contaminated the area and would be difficult to remove 100%.

I would send it back if possible. Brake fluid is one fluid that you do not want leaking on your engine bay paint.

[Pawel66]

Wallace, thank you - difficult material and difficult fluid, that is exactly why I ask.

I will send an e-mail to George, but it has been a while since I bought it...

[Cees Klumper]

Honestly Pawel, if the bottom picture is of your old reservoir, then I think it looks just fine!

[Pawel66]

Yes, it is, I took the picture right after I installed it this morning.

My wife would be happy to hear as it is her who helped me making it less yellow!

But it is yellow. For some strange reason one of the caps whitened more than the other...

Anyway, if anyone knows of a proven way to seal the Authentic Classic one, I would appreciate sharing.

I am enclosing picture: original reservoir, Authentic Classic internals.

[wwheeler]

That seal joint on the nipple is not one that should ever fail over time if it was done correctly to begin with. Rubber will fail in brake fluid, but plastic should not. How long have you had it on the car? I honestly think George would want to know if it did leak, if for nothing else, to have feedback on his products. He runs a fine company and would want to know.

That being said, you can always try to reseal it. Try finding a solvent for brake fluid (test on the plastic also) and flush the nipple out best you can. Then apply heat and maybe use like a blunt flat screwdriver at the seal joint. Or possibly just melt the end of the nipple. Most plastics will start to melt around 200*F. If you cannot send it back, you have nothing to lose.   

[Nicolas Aristodemou]

Powel maybe you could try cutting the last few mm of the nipple with a Stanley knife so that you can see the inner diameter of the tube and after you clean and dry with fresh water and a blow dryer the reservoir try filling the nipple with molten Bostic glue using a hot glue gun.

I think it should work and this material is unaffected by brake fluid.

A less attractive but easier to accomplish repair would be using a heat shrinking tube over the cleaned and dried nipple, the one you use to seal electrical connections on cables. I don’t know if you can find that in white color though. Usually they are either black or red.

[Pawel66]

Thank you for your kind attention!

I now have a couple of ideas to explore.

Finding what to flush it with and seal under heat by squeezing (screwdriver or pliers) may work. I was just afraid plastics often stick to tools when heated like that. Maybe some silicone would help. Hot glue or shrink tubes are, I think, good ideas too. I do have the white ones.

I wrote to George. Turns out I bought in 2017. The advise was to remove the plug from the nipple and plug it with something else, e.g. the solution used earlier, on 230SL, a rubber plug and clamp. But this is the last resort, I would say.

I bought several items from Authentic Classic, it is more rare than I would have wished due to shipment, duty and tax cost. I am always happy with the parts and service. These things, such as this leak, just happen sometimes.

Thank you very much for your kind advise!

[WRe]

Hi,
I would try it with a heating-up grimper and squeeze it together.
...WRe

[Pawel66]

Yes, I will figure out how to flush it and then either glue or heat.

[Pawel66]

Small update: as per information from George, who si very helpful, these containers are made of HDPE or LDPE type of plastic. I looked up the proper glue for those and it seems to be Loctite 3038. So that is what I will try.

[Shvegel]

I agree with your plan to glue it.  Most sealing of polyethylene of any thickness is done using a sonic welder which is essentially a tiny microwave oven. It heats the plastic from the inside and makes a far better seal than heating from the outside. 

[Rick Katucki]

Mine has rubber nipple, similar to the ones on a brake bleeder, and a small clamp.

[Pawel66]

Mine has rubber nipple, similar to the ones on a brake bleeder, and a small clamp.

This is the earlier solution. I think it went for early reservoirs where the nipple was in front of it. Yes, this would be an emergency solution for me, but it would not look correct and this whole situation is about the look. I would not even have to cut off the seal on the nipple, a hose would go over it. But I just swapped reservoirs, having one at hand, as it is a 15 minutes, maybe half an hour job and it offered opportunity to work on sealing the AClassic one.

[Pawel66]

Small update: as per information from George, who si very helpful, these containers are made of HDPE or LDPE type of plastic. I looked up the proper glue for those and it seems to be Loctite 3038. So that is what I will try.

I did this, poured water to the reservoir - no leaks so far. I will test it as well with brake fluid.

[DaveB]

Sounds like you have fixed it but, as it was most likely a manufacturing fault, I feel you should have been entitled to a replacement. Unless you told him you were willing to try the fix. (notwithstanding the 4 years since purchase..)