Master brake cylinders, any replacements available?

sanships · Post by **sanships** » Tue Oct 18, 2005 11:11 pm

My project has somehow lost the master brake cylinders (still investigating the loss at the shop and charge them) and will need to be replaced. I have seen other master cylinders but it does not have part numbers on it. What series of planes can I look at that will match the parts required? Early 172's, 150's? Saw in the aircraft spruce catalog of the cleveland master cylinder for $250. Is this applicable? I do have the cleveland wheel and brake conversion. Thanks!

Post by **GAHorn** » Wed Oct 19, 2005 1:46 am

The Cleveland model 10-35 can be used. It costs about $230 each. The Matco model MC-5 (vertical) claims to be a direct replacement for the Cleveland and costs about one-third as much.

sanships · Post by **sanships** » Wed Oct 19, 2005 8:28 am

George, my mechanic has looked at those and is concerned about the fitting for the parkbrake installation requiring an extra hole. Has anyone adopted either a Matco or Cleveland master cylinder on a 170 on record?

Post by **GAHorn** » Thu Oct 20, 2005 12:40 am

Extra hole? Can you elaborate on that?
Meanwhile.... I hope your parking brake is DISABLED! It is a dangerous piece of equipment, poorly designed in Cessnas. It's been discussed several times in these forums.
Basically, the problem is that in a stiff or gusty crosswind, full rudder application on final approach can result in the rudder pedal contacting the firewall insulation blanket. With the rudder pedal fully depressed, the pilot's foot will likely apply the brake while still airborne, and the contact with the firewall blanket will lift the parking brake lever on the master cylinder, thereby applying the parking brake. The pilot will have no indication that the parking brake is set on that wheel until touchdown, when the locked wheel burns the tire and veers the aircraft off the runway.

I suggest you disconnect the parking brake Bowden cable at the "yoke" just above the master cylinders, and bend the central control wire around the end of the Bowden cable's sheath. This will prevent an un-suspecting future pilot from being able to pull the parking brake knob...and he will never be under the impression he as set parking brakes. (Also, completely remove all other associated parking brake hardware from the master cylinders, in order to prevent their inadvertent deployment.)

sanships · Post by **sanships** » Thu Oct 20, 2005 7:01 am

George, I totally forgot about that! I know I've read it before in the previous topics and totally forgot when I discussed with my mechanic about all the things that should be done and procured. Again, thanks for the heads up!