When Jimmy from Jimmy’s World decided to bring an old airplane back to life, he knew there’d be surprises… just not ones this old.

Among the first things pulled from the aircraft were two Bendix magnetos, still stamped with a 1995 overhaul date. That meant these magnetos hadn’t been touched in nearly three decades. Instead of trying to make them limp along, Jimmy brought them straight toHartzell AviationTulsa, where they got the full teardown, overhaul, and rebuild treatment. 

Read on to learn what the overhaul process looked like and why it was necessary. 

When Inspection Isn’t Enough

At first, Jimmy hoped he could get away with a simple inspection. But when our techs spotted a serial number beginning with “95,” it was clear: these magnetos hadn’t been overhauled in nearly 30 years. For an ignition system that’s supposed to be inspected every 500 hours and overhauled at 4 years or 500 hours, this was way past due.

Instead of patching together questionable components, Jimmy went all in; theHartzell AviationTulsa team stripped them down and rebuilt them from the case up.

The Magneto Overhaul Process

Once Jimmy’s magnetos were on the bench, it was clear that they needed more than a checkup.

Our team fully disassembled both units, removing the impulse coupling, rotor, spark cap, and coil, which all showed signs of heavy wear and electrical damage. Anything that didn’t meet FAA standards was discarded. 

During the overhaul process,Hartzell Aviationfocused on:

Disassembly & Evaluation: The team disassembled the magnetos and immediately discarded worn components, including the impulse coupling, spark cap, and coil.

Upgrades & Replacements: Every critical part was replaced with FAA-approved components, including a high-performance coil for better output.

Cleaning & Refinishing: The housings were stripped, cleaned, and repainted, removing decades of grime in minutes.

Reassembly & Timing: Using specialized tools, the team reassembled and timed the magnetos, followed by a final quality check.

Why It Was Worth It

It would’ve been easy for Jimmy to clean up those old magnetos and hope for the best. But in aviation, hope isn’t a strategy, especially when it comes to ignition. Magnetos are mission-critical. They don’t just power the spark; they power peace of mind.

By choosing to overhaul rather than take shortcuts, Jimmy now has a pair of magnetos that are:

FAA-compliant and zero-time: These aren’t just restored; they’re reset to factory standards, with the documentation to prove it.

Safer and more reliable: Faulty magnetos can lead to engine misfires, rough running, or even total engine failure.

Optimized for modern performance: With upgraded high-output coils and fresh internals, they deliver stronger, more consistent spark energy.

And maybe most importantly, they give Jimmy the confidence to turn the key and take flight, knowing that what’s under the cowling has been done right. Because when you’re 5,000 feet in the air, the last thing you want is your magneto to fail.

Watch the Full Video

Whether you’re flying regularly or restoring a classic aircraft, your magnetos need attention. If you’re unsure when yours was last serviced, or you’re experiencing rough starts and engine stumbles, QAA’s experts can help. 

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