Stupid caliper question !

[exdirtbiker]

Time in the garage is limited. Time in front of computer is plentiful.
So....
Can failing/missing O-rings (#4 below) cause a brake fluid leak?
I rebuilt both calipers last year with oem seals, but do not remember paying much attention to the O-rings, Or if I installed the bolt with the o-rings in the correct hole.
one caliper still leaks.
I see NO fluid on the rubber boot around the piston, but the caliper braket was dripping wet...
Thanks in advance. (79 GS1000 L )

[dorkburger]

I havent dealt with single piston calipers in a long time, but if I recall, the #4 o ring is to keep dirt out of the caliper/mounting bolt cavity. The caliper moves slightly along the bolt under braking.

[hjfisk]

Shouldn't be any fluid around those o-rings

[exdirtbiker]

update... the caliper was perfectly fine, the leak was the grease ( unknown type) I put in the cavity to "help keep things from getting rusty in there".
The grease "melted" into oil in the hot garage, and oozed out all over the place, making me think I had a bad caliper.
(FYI, the pins can not be swapped even if you try )

[Nessism]

Black moly caliper grease (Permatex I think) is the stuff. High temp and won't flow away when the brakes get hot.