Folks at Barnwell this weekend mayb have noticed I spent a lot of time fooling around bleeding my brakes Saturday morning. When I landed Friday afternoon, I discovered I had no brakes at all! Good thing it's a 5000' runway there. If I'd been at home, I'd have ended up in either a swamp or a corn field, neither of which is particularly appealing. Of course I should have tested the brakes before I left, but given that they won't hold the plane at full throttle (not even close), I've developed the habit of pulling off the asphalt into the grass, and doing a quick runup in the grass to check engine operation. Apparently I never actually used the brakes to realize that they didn't exist before takeoff. Energy conservation, I guess. And yes, the checklist needs updating.
Anyway, even after bleeding from the bleeder up to the reservoir using an oil can from the bleeder end (thanks, P.F. Beck!), I still had no brake pressure on the right side, so further investigation revealed brake fluid puking out of the innards when the pedal was pushed. Probably a blown cup seal, which wasn't going to get fixed until I got home. But how to get into my 2600' long strip? I didn't even entertain the thought...I landed at nearby MDQ instead, with 6500' of runway. No problem, right? As luck would have it, given that it was the coldest morning of the year so far, I had topped the tires off before I left on Friday morning with 50 psi of air. Of course I didn't think of this until I was flying back home, or I'd have bled some out. I used well over 5000' of MDQ's runway to get stopped, and I finally switched the engine off to make the last turnout before the end. I found out this morning the runway has an uphill and a downhill, and I landed downhill. Duh. Mental note to self...pay attention to such things in the future. I came back Saturday night with new cup seals and pads, and rebuilt the brakes by flashlight, and this time the bleed job held. See the photo at http://www.n56ml.com/n891jf/brakes/toast.jpg for the culprit...pulverized brake pad and a cup seal that looks more like a fried egg than a brake fluid seal. Looks like neither belongs on an airplane! I think I see a set of Matcos or Grove brakes in my future. I have a set of "vintage" Enginetics go-kart brakes for sale though, "freshly rebuilt", if anybody's interested...... -- Mark Langford ML at N56ML.com http://www.n56ml.com
