Yellowbird

 

The Annual Report - 2005

She lives, and it wasn't too painful. Apart from the usual fluids and filters, the only extra cost to the inspection was the replacement of the brake linings, for a whopping price of $12.50 each.

A short list of minor squawks was also addressed, including:

1. Replacement of the trim rod end, to fix some play in the trim tab
2. Adjustment of the flap up-limit switch, to allow the flaps to retract completely.
3. Replacement of the aging alternator belt.
4. Replacement of two smoking rivets at the seam between the upper cowl and nose cap.
5. Replacement of a cracked fitting on the manifold pressure line.
6. Replacement of the old carburetor intake SCAT duct.

Compressions were good, at 78/80, 76/80, 78/80, and 76/80, but she had some oil on the plugs in two cylinders. Glazed cylinders or leaking rings are suspects, but the Mattituck representative I talked with felt that if that were the case, we would be seeing oil consumption far in excess of the quart or so every ten hours that we have been seeing. We're going to check the oil consumption and plugs again after a few hours and see if they warrant a closer look at the cylinders.

The only other issue that came up is one that has had us puzzled. Ever since replacing her old attitude indicator with a New Sigma Tek AI, I've seen some significant vibration of the "football" (the portion of the indicator face which pivots up and down to indicate pitch attitude) at certain engine RPM's. I've avoided prolonged operation at those RPM's pending a resolution, but so far, replacing the gyro panel shock mounts and rebalancing the propeller haven't helped. During the annual, we replaced the attitude indicator with another new one, only to experience the same vibrations as before. All the vacuum system components have checked out satisfactorily, and we haven't seen anything yet that could be causing the vibration. The gyro guru at Sigma Tek hasn't seen anything like this before, so we're all stumped. There are a few more leads we could follow, so the story's not over yet.