Master Brake cylinder reservoir

[67tiger]

Rebuilding the master brake cylinder and was wondering if there is a need to use thread sealer when re-installing the reservoir components. I'm replacing the copper crush washer but wanted to make sure these threads going into the housing seal properly. Thanks!

 

[jcking846]

Thread Sealant

The threads on the hydraulic fittings should be clean and dry. The seal is at the tubing flare, not at the threads.

JK

 

[tiger260]

Where is this copper washer you speak of?

 

[67tiger]

The copper crush washer goes between the reservoir adapter and the cylinder body, on the other side of the adapter is a rubber washer, and the reservoir.

 

[67tiger]

The threads on the hydraulic fittings should be clean and dry. The seal is at the tubing flare, not at the threads.

JK

I'm speaking to the replacement of the Adapter fitting which is what the reservoir sits on not the actual brake lines. Where the adapter goes into the cylinder body these threads may or may not require thread sealer, I'm going to pass on it as nobody here seems to have any better clue than I. Cheers!

 

[Erich]

I just installed the mc from SS. I used no sealant. The copper washer is the sealing element.
No issues.

 

[tiger260]

I've had 3 brake master cylinders completely apart in the past few months and none of them had sealant on those threads but if you would find it reassuring you could do it, BUT you have to somehow ensure that none of it gets into the cylinder itself or you could be fubar'd.

This copper washer has got my curiosity. Mine had just a plain steel washer and a rubber seal.

Is it a Girling cylinder?

 

[67tiger]

Yes it's the original Girling unit, and the copper crush washer is between the adaptor and the body of the MC, the other side of the adaptor the side the reservoir mounts to gets the rubber seal, steal washer, nut...Cheers

 

[o2bdriving]

When disassembling the reservoir, there seems to be a dab of pipe dope on the male threads of the adapter that extends into the brake fluid reservoir. Is that correct? There is a rubber seal under the reservoir and a flat washer and 1/2 nut securing the reservoir to the adapter into the master cylinder main body. Thanks

 

[IvaTiger]

When disassembling the reservoir, there seems to be a dab of pipe dope on the male threads of the adapter that extends into the brake fluid reservoir. Is that correct? There is a rubber seal under the reservoir and a flat washer and 1/2 nut securing the reservoir to the adapter into the master cylinder main body. Thanks

That is how mine is