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Magneto fell off engine

Altmuehltaler

Registered User
Germany
Good morning,
the other day the L-18C of a nearby flying club landed on our airfield. It did so not by choice but was forced to do so. The left magneto (Slick) fell of the engine (C90-8F). Has anyone seen / experienced this?4.jpeg3.jpeg
Unfortunately I did not see the mess personally. I have only these pictures.
Bjorn
 

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It appear the magneto case cracked all around next to the mounting flange. I wonder what precipitated that failure? Perhaps the magneto wasn't seated in the engine properly when the nuts were tightened?
 
Had a pipeline Cessna 150 do a 180 on takeoff when his mag fell off. Nuts backed off. Did this Slick Mag have a Bendix gasket by chance? Structural problem with mag case, poor installation procedure, mag case hitting engine mount?
 
I remember overnighting at Scottsbluff NE years ago and a Dr and his family were heading east in a Seneca. Earlier in the day they had just taken off from Idaho Falls and he saw smoke coming from the left engine. They landed and the mag was off. They had it fixed and continued on. That was an interesting trip. On my return from Flaming Gorge, I landed at Valentine NE for gas and shortly a Bonanza landed. The man with his two kids had come from Cody and he could not figure out why it would not get up to speed------until he went to put the landing gear down-----it was already down. I decided no retractable's for me.
 
It appear the magneto case cracked all around next to the mounting flange. I wonder what precipitated that failure? Perhaps the magneto wasn't seated in the engine properly when the nuts were tightened?

To me it looks like only the part of the flange cracked where the bracket sits...
 
Had a pipeline Cessna 150 do a 180 on takeoff when his mag fell off. Nuts backed off. Did this Slick Mag have a Bendix gasket by chance? Structural problem with mag case, poor installation procedure, mag case hitting engine mount?

I will try to find out if they used Bendix gaskets. You are referring to the issues with Bendix mags (especially dual mags) on Lycoming engines, don't you?

As far as I heard the plane was not coming fresh from maintenance. It was my first guess that some mistake happened working on it...
 
As stated above, it looks like there may have been a side load placed on the magneto If it was locked down with the clamps, but was up against the engine mount, the pressure and vibration would cause cracking like that.

Web
 
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Had the same thing happen on a DC9.
 

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The bracket that holds the magneto is a machined one. I cannot remember having seen one like this on a Slick magneto. I know only of brackets which are made of sheet metal. Could it be that the bracket is not the correct one?
 
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