Brakes
Master Cylinder
A couple of tiny seals will do wonders for spongy brakes. Cylinders
were off a 67-69 Cessna Skyhawk 10-21, 10-21a.
Replaced the plunger O-ring with
MS28775-110, INTSE3 N432, MIL-P-25732. Replaced the dyna-seal with
800-001-6.
Filler Plug 140-01900, vented 140-02000
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Had trouble with leaking master cylinders. I ended up replacing the 90
elbow with a bulkhead connector and a new O-Ring.
Calipers and O-Ring Leaking
Cleveland 93D
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Probably once the master cylinders were tight they blew out the seals on the
calipers because it started leaking. What I thought was going to be a pain
turned out to be very simple.
I removed the two bolts from the
calipers and one half of the disk brake pad fell on the floor. The whole assembly slides off the landing
gear. The plunger is removed with a shot of air from the air hose and the
rest of the hydraulic fluid comes out. Take some iron wool and remove all
the corrosion in the cylinder. Clean the unit and slip the new O-Ring over
the plunger.
The 0-Ring number was MS28775-224 ... PO
00036395 LN 2
When ready to re-install, fill the unit with hydraulic fluid and
install on the landing gear.
Bleeding the Brakes
I grabbed an oil can, filled it with hydraulic fluid, and attached a 12"
piece of clear plastic tubing on the end with a tie wrap. The inside diameter of the tubing
was just big enough to go over the bleed screw. Loosening the bleed screw
and attaching the plastic tubing over it was very easy. Then all I had to
do was pump the oil can and watch the top of the master cylinder until the fluid
ran out.
What could be easier? They want $47 for a
special tool in one of the catalogs I have. The oil can and plastic tube are a couple of bucks.