Hi! Klaus. Before you dismantle the caliper make sure that the whole
caliper is free to move through the two external bushes on the mounting
brackets since mine was inclined to stick and they havent been filled with
oil yet !!!!!! Congrats on your award, it must be satisfying to get
recognition
I took my effort to Cranfield in it's trailer , which cost me a lot of time
and effort , needing to interupt the paint programe , fetching and carrying
parts temporarily assembling etc. then the PFA can't even get the entry
right in the supplement least of all get my name against it !!!!!! .
Regards.
Bob H 337 G-PTAG
-----Original Message-----
From: Nigel Graham [SMTP:Nigel_Graham@intercept.com]
Sent: 13 September 1999 19:38
Cc: europa@avnet.co.uk
Subject: Re: brakes
Klaus,
The could be a number of causes of brakes binding. But I suspect the
problem
might be in the slave cylinder (At the brake disk end of the system). This
has a square section rubber "O" ring around the piston that deforms as
brake
pressure is applied, When pressure is released, the "O" ring assumes it's
original shape, forcing the piston back just far enough to clear the brake
disk. It has enough force to push the excess fluid back up to the master
cylinder, but not enough to overcome any resistance between piston and
bore.
The slave cylinders supplied by Europa were made to pattern and are not as
high a quality as the (more expensive) Cleveland systems fitted to
production aircraft. The cylinders and pistons are made from bare alloy,
leaving them susceptible to corrosion, especially if the aircraft is flown
out of farm strips where sheep or cattle are responsible for part of the
nitrogen cycle. First thing to inspect is the inside of the bore of the
cylinder outboard of the "O" ring for signs of corrosion.
The second thing to look for is signs of poor manufacture. On mine (similar
a/c number to yours), the piston had not been machined truly circular, with
signs of lathe tool "chatter". It is possible that such a piston could bind
in the bore of the cylinder.
Either way the calliper will have to be removed and the piston extracted (a
valve grinding sucker works well). The solution is to inspect the piston
for circularity and surface finish, dressing it on a lathe if work is
needed.
I would recommend having both the piston and calliper be hard anodised to
prevent further corrosion and if you go for a bright colour, it will
enhance
the appearance (mine is blue!)
And talking of enhanced appearance, can I congratulate you on you "Best
Europa" award at Cranfield. I've just received my PFA rally supplement with
a nice picture of OE-CKD.
Nigel (147)
----- Original Message -----
I had a problem with my wheel brake. I couldn't manage to set the brake in
such a way that the brake is completely free when not activated.
Anybody out there having similar problems with their brakes and any idea to
cure this??
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