Magnetos are one of the most abused components on an aircraft engine. They are under the cowling, they are very reliable, and there are two of them. But if the magneto fails, all bets are off as to what will happen. There could be minor damage to just the magneto, or there could be major damage to the engine. Preventive maintenance is a key element to avoiding magneto failure. Having your magneto inspected regularly, and repaired, or overhauled as required is cheaper than having your engine replaced and possibly having to do major repairs to your airframe.

The impulse coupling needs to be looked at routinely. If the flyweights become magnetized over time, then they will not engage the flyweight stops and the engine becomes hard to start, if it starts. If the flyweight pivot pins wear, the flyweights tend to strike the stop pins at rpm. Just a little at first, then as time goes they can fully engage. The flyweight then disintegrates and all the pieces fall into the accessory gear train, breaking off gear teeth and failing the engine. Makes for a bad day.

Coils and capacitors need to be tested to make sure they are within limits. Bearings wear also. Not only the ball bearing, but also the bearing races, and over time, the bearing races could start spinning in the magneto housing. If this happens, the shaft starts wobbling and starts causing other damage. The bearings needs to be repacked with fresh grease. The grease will "dry out" and get hard and not do what it is supposed to do, lubrication.

We test the magneto to manufacture recommendations and record items like the coming in speed, coupling engage and disengage rpm. This testing can take a little as 20 minutes, or as long as a couple of hours on the test stand.

We currently inspect, repair and overhaul Bendix and Slick magnetos. Repair of either magneto can also be accomplished at our facility. If you think that your Slick magneto is in bad enough shape to overhaul, then you will probably be better off trading it in and buying a new magneto. We can overhaul your Slick magneto if you want it overhauled, but Slick parts are expensive compared to the Bendix magneto.

The inspections and overhaul criteria in the manuals are the manufactures recommendations. We highly recommend that the magnetos at least be looked at every 500 hours or 4 years. This does not mean overhaul, just inspect for any damage, corrosion, lubrication, and ran on a test stand to ensure that they are operating correctly. Basicly, an IRAN, inspect repair as necessary. Cheap insurance considering what can happen if it fails for something that could have been detected and corrected.