Mark89114

grey metal dust around alternator

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Changing the oil on my Mooney Ovation and I go over all fittings, connections, etc. under the cowling and saw this gray looking dust on air intake.  Further investigation and you can see where it is coming from around the alternator.  The alternator was overhauled I am guessing about 100+ hours ago.  I also just recently spend about 2 hours flying in icing with the TKS fluid so wondering if that is causing any type of issues with washing "dirt" out of alternator?  I called my mechanic and he suggested possibility of the bolts being loose and fretting.  I did run my finger out of the alternator exhaust and nothing really there.  Any thoughts?

 

  20181204_190728.thumb.jpg.3696b1209b4ff3e3061c8909f95aa588.jpg20181204_190829.thumb.jpg.dd2d951f3b884e5506dab1a738989239.jpg  

 

 

20181204_190723.jpg

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that is probably from the brushes in the alternator, I would be looking at what you want to replace it with. I personally like the plane power replacements.

Brian

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See if there is any break-in advice for the alternator...?

Sharp square ends of the brushes may have a high wear-in phase...before conforming with the

 round shape they are following...(?)

In the mean time... clean the dusty mess and see if it comes back... (?)

New IO550 alternator, excessive dust, pics... an invite for @M20Doc to take a look as well...

I’m not a mechanic...

 

Best regards,

-a-

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34 minutes ago, orionflt said:

that is probably from the brushes in the alternator, I would be looking at what you want to replace it with. I personally like the plane power replacements.

Brian

Us fancy Mooney Ovation owner have fancy geared alternators connected to internal gears on the engine, so I don't think that is an option.  

 

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1 minute ago, Mark89114 said:

Us fancy Mooney Ovation owner have fancy geared alternators connected to internal gears on the engine, so I don't think that is an option.  

 

they have direct drive replacements

Brian

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15 minutes ago, carusoam said:

See if there is any break-in advice for the alternator...?

Sharp square ends of the brushes may have a high wear-in phase...before conforming with the

 round shape they are following...(?)

In the mean time... clean the dusty mess and see if it comes back... (?)

New IO550 alternator, excessive dust, pics... an invite for @M20Doc to take a look as well...

I’m not a mechanic...

 

Best regards,

-a-

I am not in a panic mode that this is going to cost me money yet......visiting my mechanic tomorrow and will see what he has to say.  

 

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just took a look and what they have are rebuilt not new replacement. looks like nothing worth getting your hopes up for. sorry.

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I get that grey dust washed from the TKS on the prop slinger also. I get it all over the engine. Maybe just airflow is making it look like from the alternator?  

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There is a replacement option.  When mine started giving me grief, it made more sense to replace it with a new one of these than rebuild.  So far so good and a few pounds lighter off the nose.

https://www.aircraftspruce.com/pages/st/manu_hartzell/alv9610alternator.php

That said, if it isn't in the exhaust opening from the alternator itself, that probably came from around the alternator not the alternator itself.   I would clean it up and see if you can figure out where its coming from.  I don't think I'd be ready to swap the alternator right away.  There's also a pretty expensive coupler in there.  If it wasn't replaced at the last overhaul, that might need to be replaced too.  I changed mine out while we were in there.

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6 hours ago, Mark89114 said:

Changing the oil on my Mooney Ovation and I go over all fittings, connections, etc. under the cowling and saw this gray looking dust on air intake.  Further investigation and you can see where it is coming from around the alternator.  The alternator was overhauled I am guessing about 100+ hours ago.  I also just recently spend about 2 hours flying in icing with the TKS fluid so wondering if that is causing any type of issues with washing "dirt" out of alternator?  I called my mechanic and he suggested possibility of the bolts being loose and fretting.  I did run my finger out of the alternator exhaust and nothing really there.  Any thoughts?

 

  20181204_190728.thumb.jpg.3696b1209b4ff3e3061c8909f95aa588.jpg20181204_190829.thumb.jpg.dd2d951f3b884e5506dab1a738989239.jpg  

 

 

20181204_190723.jpg

I would remove the composite cover from the alternator then grasp the outer end of the alternator and give it a good twist to see if the 2 halves are loose at the tie bolts.

Clarence

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Update.....my mechanic looked at it and thinks it is from the composite cover wearing against the housing.  The two halves were tight and the alternator bolts are all snug, no movement.  Going to clean it up and see what happens.  Will keep an eye on it obviously.  

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52 minutes ago, Mark89114 said:

Update.....my mechanic looked at it and thinks it is from the composite cover wearing against the housing.  The two halves were tight and the alternator bolts are all snug, no movement.  Going to clean it up and see what happens.  Will keep an eye on it obviously.  

that's good news

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Anyone know why that shroud is really even there?  The parts book shows a hose on that exhaust port but I never had that.  I find it hard to believe its necessary for cooling with teh alternator directly in the stream of the blast air.  All it seems to do is direct air down and away from the cylinders.

Can the shroud be taken off for a while to see if the grey dust goes away?

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The shroud helps direct air into the alternator then out the lower vent tube.

Clarence

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