Scintilla Magneto Manual Jun 2026

Connect a synchronized timing indicator (such as a Bendix black box or digital magneto timer) across the breaker points and ground. Rotate the entire magneto housing slightly against the direction of rotation until the light or buzzer indicates the exact moment of point opening. Tighten the mounting bolts firmly to the specified torque. 3. Routine Inspection and Maintenance

: Use a non-magnetic feeler gauge. The standard gap for many Scintilla models is .012" to .015"

If you’ve ever tried to start a pre-1960s chainsaw, outboard motor, or military generator, you’ve likely met a Scintilla magneto. Before the days of reliable batteries and CDI boxes, Scintilla (now a part of the Bosch empire) was the gold standard for high-voltage ignition. These units are legendary for their durability—but legendary also means old .

Apply one drop of light aircraft engine oil to the cam lubricator felt. Do not over-lubricate; excess oil ruins the breaker points. Every 500 Operating Hours scintilla magneto manual

| Symptom | Likely Cause | Remedy | | :--- | :--- | :--- | | No spark at the plugs | Faulty plug or lead (most common) | Check and replace spark plugs and leads. | | | | Ensure there is no unintended path to ground. Disconnect the shut-off wire to test. | | | Hard/flexible central king lead | Coil replacement. | | | Points not opening or badly burned | Set gap or replace points and condenser. | | Weak or intermittent spark | Worn or oily points | Clean or replace points. | | | Low RPM cranking speed (especially for engines lacking an impulse coupling) | Check battery or starter system. | | | Carbon tracking in distributor cap | Replace distributor cap. | | Rough running / missing | Old or incorrect spark plug wires (resistive type) | Replace with solid-core, non-resistor plug wires. | | | Loose or broken internal connections | Inspect and re-solder connections. |

Test the insulation resistance of the coil using a megohmmeter.

Consists of a few hundred turns of heavy copper wire, a set of mechanical breaker points, and a capacitor (condenser). Connect a synchronized timing indicator (such as a

The primary circuit connects to the cockpit ignition switch via a wire called the P-lead.

This article serves as a comprehensive guide. We will explore the history of Scintilla magnetos, explain what you will find inside a factory manual, provide common troubleshooting steps, and tell you where to locate these rare documents.

Inspect the contact surfaces. They should be smooth and free of excessive pitting, oil, or white oxidation. Electrical Testing Before the days of reliable batteries and CDI

Once the internal timing is set, mount the magneto to the engine. Step 1: Prep the Engine

Without the manual, you won’t know:

When turning the engine over by hand prior to start, you should hear a loud, distinct metallic "snap" from the magneto. Absence of this sound means the spring is broken or the latches are gummed with congealed grease. Wash the mechanism out with clean mineral spirits and relubricate with a light, cold-weather lubricant.