Extreme compass deviation

[rudyhiller]

Recently I have noticed the magnetic compass in my 46 C140 has been way off, it’s never been perfect but now it’s 50+ degrees off and inconsistent- can’t make a compass card for it. Also, it’s the worst when east and west; north and south are accurate.

Using another compass, it seems that the magnetic field is from the electric starter. I have the original starter on the C-85-12. Has anyone else experienced this? Is it possible that a winding in the starters armature broke and is causing excessive residual magnetism?

TIA!

[rudyhiller]

I’ll also add, switching the master switch on/off makes no difference

[8281]

With everything electrical in the Off position , touch a screwdriver or some type of steel to the
Starter housing to see if it is Magnetized.

Or

Get a Boy scout compass and move it around to different parts to
see if the North Pole Needle points to the suspected item!

And if it is the Starter, have the Armature De-magnetized !

[8281]

My mistake / ! No need to use a compass. as it will point to steel anyway!

Just use the screwdriver method!

[6643]

If the armature was magnetized, I don't think the starter would turn! The field poles, on the other hand, probably are. Also, if you have a generator, the field poles will be magnetized. But, then, they all are, so, everyone would have the same problem.

Have you tried to swing the compass and adjust the compensating magnets?

Take the compass out of the plane and see if it exhibits the same behavior.