Master Cylinder Copper Washer leak

[Bill W]

Go the the plumbing section of any big box or hardware store and tell them you need a 1 1/4" o-ring for a p-trap ( or drain tube ) Slip joint. Heck they only make two sizes ( 1 1/4" & 1 1/2" ).

 

[glcaines]

If you search on Google, you'll find several sources for copper crush washers of all sizes. As other have stated, once they are used, they should be replaced with new crush washers.

 

[drivebymashing]

I finally installed my copper washer...It fixed the leak everything works perfect now.!! I wish I installed a valve to bleed the brakes with pressure bleeder though.

 

[Kharville]

I had the same issue with mine last summer when I replaced all my master cylinder, airpack, brake lines and all my airlines. I ended up using a plumbing o-ring in place of the copper washer. It worked great. Best part is you don't have to crank the lid down as tight either. Then I added some other parts to allow me to attach my remote reservoir line.

The first pic shows how it originally was set up. What I didn't like was 2 -fold.
1. When attaching the remote reservoir line, it is a pain to bleed the air out of it.
2. to make it easier to bleed the brakes and not have to remove the reservoir.

The way I set up gives me a shut off valve. and a plug that can be removed to bleed the air out of the remote reservoir line or bleed the brakes.

This combined with the rubber o-ring has stopped all seeping or leaks from the top of the reservoir. Now everything stays dry and if it isn't...I know there is a problem.

Where can a brass shutoff valve with NPT be found? I only seem to find them with compression fittings.

 

[bonedoc]

Where can a brass shutoff valve with NPT be found? I only seem to find them with compression fittings.

I got it through McMaster Carr. They have pretty much anything you could need.

Here are the part numbers I used

This is the ball valve 4112T53 Here are the other pieces. The male T screwed into the top of the mastercylinder. The plug seals the female end pointing up. If you need any info just ask or check out my write up Bonedoc's M35A2 modification thread, it is entry #149 on page 15. 50785K219 50785K112