Rear Master Cylinder drain plug

[dansmith65]

I didn't take proper photos when disassembling, does this look like the correct drain plug screw?
Also, should it just have a washer? Or maybe an o-ring? I was thinking of annealing an old copper washer from a banjo bolt for it; does that seem like a good idea?

P.S. The bolt does fit, so I'm not worried about that. But I have many components disassembled right now, so I'm mostly just making sure the correct bolt goes back in the correct spot.

[DiverRay]

The two threaded holes sticking up are mounts, the one in front of the bolt is for the brake line. The bolt pictured is one of the mount bolts? If it is, it should have a lock washer on it. This is all on memory at 10:00pm local time, and I'm not sure if you have a newer bike with the linked system.

[bikerphil]

Yes, that is the correct bolt, I think (not 100% sure) there is a thin sealing washer that goes in between, if it got lost, a copper washer should work.

The brake line attaches to a fitting not shown in the picture, it is on the underside of the unit the way it is sitting.

That bolt would be taken out and another line added to create a linked system.

[DiverRay]

Thanks Phil, I've only worked on the early MC's. I knew linked was '81, but didn't know about the change over of the MC.

[dansmith65]

Thanks for the input. I did have a silver-colored washer in the same container as I found this bolt, so that must have been for this as well.

[DiverRay]

That should be aluminum, but I think a copper would be better. Either way, you should NOT re-use the aluminum washer, as it may leak and cause air in the system down the road.

[dansmith65]

After inspecting the silver colored washer closer, I do see the impression of that bolt head in it, so that was definitely the one. It's slightly magnetic, so not aluminum. A copper washer from a banjo bolt is almost the same size, and possibly even a better fit. I've already annealed one, so I'll use that instead.

[bikerphil]

Thanks Phil, I've only worked on the early MC's. I knew linked was '81, but didn't know about the change over of the MC.

Yep, both of my 79's have that extra bolt/outlet too. I kinda assumed all of them have it.