Saturday, October 16, 2004

Reassembly and testing

I reassembled my MX the week after transport to Fort Deposit by truck. Nothing unusual happened during the process of putting it back together. I removed the seized engine and took it home for disassembly and inspection. The cause of the seizure was a crank-end rod bearing that melted. Not sure what caused it, but this was engine #2 from the same person that had problems and I was done buying engines from him.

I ended up working an exchange deal with Mark Smith of Tri-State Kite Sales in Mt. Vernon, Indiana. I traded him my seized Rotax 503 engine plus a good 503 crankshaft sent under warranty from the guy who sold me the first two engines. I also sent two new aftermarket OEM style pistons that I was going to use to rebuild the 503 sent on trade. What I got in return was a Single carb Dual CD ignition ultralight 503 with provision to mount a gearbox (8 mounting holes and a flange). This engine was removed from an ultralight and replaced with another engine. I was told it had about 300 or so hours on it. I trust Mark, so I believe the hours are fairly accurate. I got this engine with the traded components for $1000. All told, I probably had just at $1700 into this latest engine, a fair price for a 300 hour, late model 503. New 503's go for over $3000. It was a deep hit to my pocketbook that I'm just now (January 2005) recovering from.

After installing the new (used) 503 and finding some damage due to rough UPS shipping, I pulled the engine back off and took it home to correct the problem. The next day I re-installed the engine and started it up for a test. After priming the engine with a squirt of fuel, it fired on the first pull of the rope and started on the second pull. It appeared that I was finally going to get to see the area around my new home from the air!

I let the engine warm up and I strapped in. I taxied out to the paved runway and stopped on the hold line, checking for traffic. Finding none, I taxied out on the runway to the end and turned around, smoothly advanced the throttle and started the takeoff roll. Within seconds I was airborne! I continued to climb, checking the engine gauges during the entire process. Tachometer read 6200 at full throttle while climbing. Exhaust gas temperature was about 1125-1150 (good) and Cylinder head temps were both about 325. Everything seemed to be working properly and I pulled back the throttle to about 5400 RPMs for cruise speed and started do traffic patterns around the airport while familiarizing myself with the terrain layout.

The airport runway is oriented South South-East with heading of 150 and 330 and corresponding numbers of 15 (northerly approach) and 33 (southerly approach). Trees and such lie to the west of the runway, with the town of Fort Deposit to the northeast and some large pastures to the southeast. Interstate 65 roughly parallels the runway off to the east about 3 or 4 miles. The city of Greenville, Alabama lies to the south about 10 miles distant and you can see the Greenville area at 800 feet above the ground on a clear day. There are a few small pastures to the northeast with a bunch of trees and forest to the north. If you venture out over the forests 10 miles to the north or north northeast, many more large pastures extend for several miles, starting just west of the interstate. It's not the ideal place to fly out of, but it's tolerable. The runway is 3600 feet long and there's plenty of room to gain altitude while still over the runway. If you should have an engine out halfway down the runway, you would be at sufficient altitude to either land straight ahead or turn around and land, both on the runway. If you have an engine out over the south end of the runway there are fields closeby to land in. The north end of the runway is all trees so precautions must be taken if the prevailing wind determines that you need to take off to the north.

After an hour of local flight testing, I arrive back at the airport and land. I'm satisfied that the engine performs well, but I'll always be wary of a failure in the future. All the experts say that it's not a matter of IF but a matter of WHEN. I'll fly accordingly!


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