Land Rover brake master cylinder seals leak,

OK, just so everybody know what I'm talking about here is the dual brake system with servo. This unit , NRC6096, is for Series 3 dual line systems. It has the plastic reservoir connected to the casting with seals. It is these seals which leak.

During my restomod when I went to disc brakes I upgraded the old mc with a servo and a new mc in May of 2013. It took a while to get the vehicle running enough to put brake fluid in, Girling DOT4, I don't have that date at hand. I drove the 109 for about 6 months while trying to sort out the 19J engine. That ended last Dec, 2014.

   In Jan of 2015 when I started to change out the 19J 2.5DT for the 200TDI I noticed the seal connecting the brake fluid res to the mc was leaking and I got a new one, then swapped them out in March. Haven't driven the 109 anywhere and the new mc is leaking at those same seals 4 months later.

I took apart the original and the first new mc's hoping to find out why they were leaking. There must have been an upgrade at some point cause the original ones had flat sided seals and the new ones are stepped for recess in the casting.

Old one with res off;

New seal on left old style on right;

I think it is impractical to be replacing seals every 4 months so I am going to change the LR mc for a Dorman M71248 out of a 68 Mustang. It has an integral res in the casting so there will not be any leaking seals.

I don't have one yet so no pictures. Next post!!!