Prop click when manually turned.

PilotPaul said:
A friend and I were preflighting my Cessna 150 when we found the following. When I manually turn the prop on my Cessna 150,there is a distinct "click" feel to the prop, similar to what you would notice when turning a watch. Plus there is a clicking sound in the cowling.
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I wonder?? do you have a pull start or a key start?
 
Starter drive?:dunno: Without hearing the click to determine the material, it's wild guesses.
 
Henning said:
Starter drive?:dunno: Without hearing the click to determine the material, it's wild guesses.
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Do you know how a pull starter works on a 0-200/0-300?

They can be left engaged.
 

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Tom-D said:
How many alternators have you changed for a bearing failure?
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I have found corroded bearings. I have replaced a wheel bearing that made a similar noise because its inner race was split.

Just because many mechanics have never found a bad alternator bearing doesn't mean it's impossible.

I spent years in a machine shop rebuilding compressors (12,000 of them, among many thousands more control components and actuators) before I went full time into aviation. I heard dozens of bad ball bearings from compressors make exactly that noise.

Dan
 
Dan Thomas said:
I have found corroded bearings. I have replaced a wheel bearing that made a similar noise because its inner race was split.

Just because many mechanics have never found a bad alternator bearing doesn't mean it's impossible.

I spent years in a machine shop rebuilding compressors (12,000 of them, among many thousands more control components and actuators) before I went full time into aviation. I heard dozens of bad ball bearings from compressors make exactly that noise.

Dan
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Have you ever taken a cessna alternator apart? If you have you'll know why they never fail.

They are a double row sealed ball bearing that is replaced at every overhaul of the alternator, which is about 1/10th of the bearing's designed life.

They are nothing like a wheel bearing which is a caged tapered roller, and exposed to weather, I have no idea what's in a compressor, but i'll bet they are not holding a free spinning balanced magnet
 
Tom-D said:
Have you ever taken a cessna alternator apart? If you have you'll know why they never fail.

They are a double row sealed ball bearing that is replaced at every overhaul of the alternator, which is about 1/10th of the bearing's designed life.

They are nothing like a wheel bearing which is a caged tapered roller, and exposed to weather, I have no idea what's in a compressor, but i'll bet they are not holding a free spinning balanced magnet
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That gear-driven alternator has the same X-4610 single-row ball bearing that the other Ford-based alternators do. I have replaced them. And I have found them really tired and rough when they've sat for a long time.

The compressors (on heavy trucks and earthmoving eqiuipment) ran up to 3000 RPM. The bearings were the crankshaft bearings, most commonly in compressors that were either belt-driven or driven by small gears that imparted significant radial loads on them. They were engine oil lubricated and the engines ran almost constantly in commercial service so corrosion wasn't usually a problem, but we still found corrosion sometimes. More often it was a split inner race from the tight press fit on the crank. Any tiny flaw in the metal would let it crack. The split inner race on the 150's main wheel bearing wasn't a press fit, but it had split anyway even though it had no excuse to do so. Bearings do occasionally fail.

I hope the OP posts whatever is found to be making that noise. We could all learn something.

Dan
 
Dan Thomas said:
That gear-driven alternator has the same X-4610 single-row ball bearing that the other Ford-based alternators do. I have replaced them. And I have found them really tired and rough when they've sat for a long time.Dan
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What ever Dan.

simply show me the maintenance difficulty reports to support your theory.
 
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