Eureka!
I've finally managed to bleed the air out of my finger brake master
cylinder.
After cleaning up and installing my cylinder, the starboard side was
solid with just about 1 inch travel on the lever but the port side was
spongy with about 2in. I must have bled about a litre of fluid through
this side trying to eliminate the air without success I then decided to
look on the 'net for possible solutions. It seems that it is a good idea
to 'bench bleed' a master cylinder before fitting to eliminate any air
which may be difficult to evacuate after fitting. Thinking about this
and not wanting to disassemble the system again, I looked at my setup. I
decided that as the cylinder is not quite level and the outlet from the
master cylinder to the brakes is at the low end, there may be some air
in the cylinder which cannot be eliminated by normal bleeding.
My solution was simply to back the aircraft up a pair of car ramps,
leaving the nose wheel on the floor to level the cylinder in situ then
bled the port side again. Lo and behold a good quantity of bubbles
issued forth and now I have good solid brakes on both sides.
I guess if doing it again, I would try to bench bleed the cylinder and
install it filled if possible to eliminate this problem.
Richard Iddon. (G-RIXS hoping to be flying again soon after installing
the brakes and fitting speed kit).
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