brake fluid reservoir disc/ washer

[JJH]

I have a '79 R65.  I am missing the "brake fluid reservoir disc/ washer" it is #14   "32 72 1 238 388       WASHER" on the fiche.  I am leaking a small amount of brake fluid from the reservoir area and I thought this might be the cause.  I have bleed the brakes with new fluid and it has a new "rubber boot"/ diaphragm in the reservoir.  The brakes themselves work well, no spongy or soft lever feel.  Any ideas on where this leak my be coming from?  As I said it is a small leak, just a drop is found on the underside of the brakes, but it is "wet" all around, but that could just be from the vibration of riding, so I don't actually know where it is leaking from.

Thanks,
John

[Barry]

John,

I changed the fluid on my 79 recently and didn't recall seeing this washer so I've just been out to the garage and removed the reservoir lid to have a look for you. At first I thought I didn't have it either because it didn't come away with the lid. Then I realised it was stuck to the rubber bellows and here's the thing it doesn't look at all like the image in the fiche. It is a washer of sorts in that it's a disc with a hole in it but the hole matches the internal profile of the bellows which is not circular and there is a short flange that locates inside the bellows.  It's made of hard plastic so I'm not sure what role it has in providing the seal unless it's just a spacer to provide compression of the flange on the rubber bellows.


The other possible source of a fluid leak could be the joint between the plastic reservoir and the casting. Although I've not had that problem with mine I seem to recall it might not be fixable.

[Tony Smith]

The other possible source of a fluid leak could be the joint between the plastic reservoir and the casting.

Pray that it is not that on a round reservoir. The seal is readily available - it is just an "O" ring, the problem is that removal of the reservoir usually destroys it and you can't buy new ones. I am hoping that the ones intended for Ducati and the like will fit (available from Bevel Heaven etc) and am waiting for someone else to spend the money so I know.

I have a twin 4-spot conversion ready to go needing only a 17mm kit in the spare "round" master cylinder I have in stock and a new reservoir  seal.

I don't want to spend the money on a master cylinder kit and spend the time boring it out and sleeving it if I am never going to get a reservoir for it. A new master cylinder requires saving up for.