On my Kitfox 3 I have eight inch rims with Matco brakes. Even though I have bled them a number of times the right brake has not the power of the left one. Is there a way to adjust the pads? I sure this is simple to some but I am baffled.
On my Kitfox 3 I have eight inch rims with Matco brakes. Even though I have bled them a number of times the right brake has not the power of the left one. Is there a way to adjust the pads? I sure this is simple to some but I am baffled.
Based on automotive experience with disc brakes, there is no adjustment. The system is quite simple. If bleeding is not the resolution, I would look at fluid flow. Are the seals in the cylinder good? Is the brake line rubber or metal? If rubber, has it ever been kinked? The rubber lines can fail internally. Do the components at the wheel move freely?
Lou
KitFox II
582
Contamination on the right side brake pads? Are both disks equally smooth surface finish?
Thanks for the suggestions. After the holiday weekend I will try Matco directly. Meanwhile, I will jack that wheel to see if there is any slipping or dragging. The plane had been on floats for years. When I got it I reinstalled the landing gear/brakes. I flushed it all using the 5606 aircraft brake oil and installed all new lines. There appears to be no leaks but rechecking cannot hurt. Thanks again. Also I plan to adjust the length of the master cylinder rod on the pedal.
Welcome to the club. I have a type III with absolutely lackluster brakes. Here are some of the things I've done. I changed the brake pedal geometry, installed new wheel cylinders, bled gallons of fluid through both sides. It is impossible to lock a wheel and pivot the airplane around on one wheel. The pedals are definitely not firm.
I've written to MATCO and was referred to their web site where they have a wealth of information there. It's just a matter of diving in and going through the hassle again.
One of the most significant pieces of information they offered, was that you must have a pressure of 450psi at the wheel cylinders to achieve maximum breaking. Interesting enough, any more than that can actually reduce brake effectiveness due to deformation of the wheel cylinders. I have a pressure gage ordered and will start on it once again once it's received.
Spend a little time poking around in their web site and you'll find a wealth of information there.
Happy Hunting,
Chuck Gruby
Petal, Kit Fox III Flying
I got the whole right wheel assembly apart today. I have to say the plane had been on floats since '93 and the wheel/strut assemblies had been stored in a warehouse. I had put fresh oil through them before attaching but never disassembled the brake units. I found some gunk in and around them. it looks like oil that had been on them for years and mixed the dust dropping on them from years of storage. I want to spray the pad surfaces with brake cleaning fluid. Is that acceptable?
I found trouble shooting tips on Matco's site. I used their suggestion to sand the pad surfaces with 220 grit. I used a rifle bore brass brush to clean the insides of the tubes that allow the pads to move freely and polished the outside of same. Upon re-assembly I found no additional braking power. Maybe just the fact that I have 22" dia tundra tires gives the plane too big of a lever for these brakes designed so long ago. I'm going with the Fred Flintstone method of dragging my feet!
I could never get my Matco brakes to work acceptably either.
When I converted to Grove gear, I used their double puck calipers on "normal" 6" wheels (with 22" Desser tires) with no change to the peddles or Matco masters. These brakes are now strong enough to hold the plane at a full power run-up, or even nose it over if I wanted.
I believe that the internal caliper design is just a poor performing setup.