Jump to content

'02 GS Rear Master Cylinder Replacement Question

Jim Moore

Recommended Posts



I just replaced the rear master cylinder on my R1150GS. The install was pretty easy, thanks in large part my new favorite tool, the MityVac. I seem to have a little fluid seeping past the threads when I use the brake. Should I have taped the threads before I screwed the brake line into the master cylinder? if so, what kind of tape?




Link to comment

No Teflon tape in brake circuits! It’s pretty much the bane of brake technicians everywhere. Use a correct thread sealing compound made especially for braking systems.

Link to comment

Jim, if you have fluid leaking past the fitting threads you have an issue with where the brake line seats in the master cylinder..


The fluid shouldn’t even get as far as the threads if the line is sealing properly where it is supposed to at the line flair to the master cylinder.. That threaded furrel just holds the line tight into it’s sealing seat it isn’t meant as a sealing area..


It sounds like you might have something trapped between the line flair & it’s seat,, or the line bubble is distorted,, or it isn’t tight enough,, or possibly the flair is cracked..


Might be worth pulling the line back off & finding out why it isn’t sealing correctly..





Link to comment


This topic is now archived and is closed to further replies.

  • Create New...