C177RG pilot reports malfunctioning landing gear down indication light. After inspection and repairs by a mechanic the nose gear collapsed on the next landing.

Narrative

The gear was lowered at 115 KTS but we had no green light; a horn; and gear down. On shutdown we noted that the circuit breaker had popped. At restarting we had green light; no horn; and normal operation. My Mechanic advised me that I could bring the aircraft over to him; for a checkout (traveling gear down). The gear seemed solid and I believe it was. I landed without incident. The airplane was put on jacks and gear cycled but the green light was not displaying. The Mechanic discovered a loose wire in the micro-switch and direct wired the switch. Following that the gear went up and down and the light indicator worked correctly. After re-assembling; with the repair made -- the last flaps of the gear door did not quite close the same. He trimmed some metal from the doors but concluded that the wheel was not going up far enough. The problem seemed traceable to a rotating linkage with an adjustable nut. The Mechanic made adjustments so that the wheel was pulling up about where it should be and the gear doors were closing pretty well. There was some doubt about the original configuration but the repair was deemed suitable. After takeoff and at the 400 FT check -- the gear operated normally and showed an orange 'up' light. I picked up ATIS and contacted Approach. At landing checklist on base; the green gear indicator light; and wheels were observed. At the 500 FT check; down indications were normal. Landing on the mains; 65 KTS; power was at idle. On lowering the nose; it felt soft. I slowed the aircraft with the yoke and slid to a stop. Hindsight lessons: 1) The best decision would have been to have left the airplane in the hangar after the first landing light indication anomaly and the popped breaker. Maintenance could have been called to jack up and test the airplane in the hangar. 2) An improvised solution was used. The direct wiring solution that looked like the light at the end of the tunnel was instead like the light of an oncoming train. 3) Maintenance was not recorded in the aircraft log -- this procedure could have encouraged greater prudence in the methods employed by showing better accountability. 4) I feel if I had been more aware of the possibility of collapse; I could have saved the airplane from great damage. If I had had the presence of mind to put in power and taxi on the mains on the long runway and then; with the nose up -- pull the mixture and shutoff the engine before stopping -- thereby decreasing the chance of a prop strike. 5) The lure of making a trip home added a certain weight to the push to complete the repair that day. One needs to be dispassionate about the length of time required while maintaining the best professional methods. 6) I blocked the only usable runway at a commercial airport and could have caused a problem for traffic -- it was not worth the risk. 7) There are many wonderful people waiting to help out in this kind of event -- it is best not to take the risk of needing to use their help. Someone else might have needed help. 8) The Mechanic worked really hard and impressively; however in this case it was not enough. It would have been better to suggest that the Mechanic take his time and follow down the procedure more thoroughly. My optimism was unwarranted.