Posted: Wed Dec 03, 2003 3:02 pm
I had the same kind of leaks, mainly on one side (left). I kept adding, bleeding, etc, I'd have brakes for a couple of landings, then they'd go mushy, no more pedal, and I was getting fluid spitting out around the cylinder rod. At last year's annual, I paid to get master cylinders pulled, lines blown clean, seals changed and new 5606, new linings, etc... I had bought 2 seal kits from Spruce. Turns out they were not the right ones. So, had to buyt that from the shop doing the annual. Brakes were OK for a while, in fact lasted from July to September, needing bleeding only once (big improvement).
Then came ski season. Remove the wheels, install the spacer blocks for the calipers, fly for a few months on skis and back to wheels. Well, the left master cylinder was leaking at the top again...
The problem is now completely resolved. I pulled the master cylinders off the plane (it had not been done), thouroughly cleaned the bowls and other parts, replaced all seals with FAA approved replacement seals found at NAPA! flushed the lines with fresh, clean Dextron II; new linings and re-installed the masters, filled and bled the system and its been 135 hours of no more problems or leaks or needing to bleed or add fluid. Any little bit of abrasive (dust, sand dirt) in the fluid will end up on the seals and cause a scuff and a leak; thus, even if the bowl isn't full, the fluid will by-pass the leaky seal out the piston rod; "path of less resistance". Flush and clean your system, install new seals, make sure the vent hoes are not obstructed and bleed the system and you too will have good brakes and no more mess. JD
Then came ski season. Remove the wheels, install the spacer blocks for the calipers, fly for a few months on skis and back to wheels. Well, the left master cylinder was leaking at the top again...
The problem is now completely resolved. I pulled the master cylinders off the plane (it had not been done), thouroughly cleaned the bowls and other parts, replaced all seals with FAA approved replacement seals found at NAPA! flushed the lines with fresh, clean Dextron II; new linings and re-installed the masters, filled and bled the system and its been 135 hours of no more problems or leaks or needing to bleed or add fluid. Any little bit of abrasive (dust, sand dirt) in the fluid will end up on the seals and cause a scuff and a leak; thus, even if the bowl isn't full, the fluid will by-pass the leaky seal out the piston rod; "path of less resistance". Flush and clean your system, install new seals, make sure the vent hoes are not obstructed and bleed the system and you too will have good brakes and no more mess. JD