gtgt_bangbang
New member
the undertank brake master cylinder has a pressure switch on end , to operate the brake light.
('78 R100 , https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51651&rnd=09082020, BRAKES 34_ 0606)
Several references indicate this pressure switch requires a crush washer to seal it on master body.
Although the Maxbmw DIAGRAM doesn't show a crush washer, they list a seal ring (10 x 13.5 . aluminum) for use with that switch.
I assembled mine with crush washer, expecting switch to crush against it, but the switch's threads bottom out a couple mm before engaging the washer,
as if the switch is taper pipe thread. . I dont recall what the assembly was like before rebuild .....
QUESTION - any one have some info on this ?
Does YOUR undertank master cylinder use a crush washer or it is (self-sealing) pipe thread ?
Rather not fill the brakes with fluid just to find out if it leaks on new frame paint !
thanks in advance
('78 R100 , https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51651&rnd=09082020, BRAKES 34_ 0606)
Several references indicate this pressure switch requires a crush washer to seal it on master body.
Although the Maxbmw DIAGRAM doesn't show a crush washer, they list a seal ring (10 x 13.5 . aluminum) for use with that switch.
I assembled mine with crush washer, expecting switch to crush against it, but the switch's threads bottom out a couple mm before engaging the washer,
as if the switch is taper pipe thread. . I dont recall what the assembly was like before rebuild .....
QUESTION - any one have some info on this ?
Does YOUR undertank master cylinder use a crush washer or it is (self-sealing) pipe thread ?
Rather not fill the brakes with fluid just to find out if it leaks on new frame paint !
thanks in advance