Armature-magneto 591420

Tested if there was a spark , there was no spark. Replaced spark plug, still no spark. Replaced the Magneto, the engine worked normal.
I learned how to replace the Magneto by looking at the assembly drawing of the engine, available on ereplacementparts web site.

It was a very easy repair. I removed the cover from the top of the engine, then I removed the small bolt holding the engine governor air flow sensor, then I removed the last bolt remaining in the magneto. I unplugged the spark plug wire, lifted the magneto and unplugged the low tension wire from underneath. I reversed the procedure to install the new magneto with one exception, I tore two small pieces of cardboard from the lid of the box that the part came in to use as spacers between the magneto and the flywheel of the mower. After I had the bolts for the magneto snugged down I removed the cardboard spacers and finished assembly.

My edger is 27 years old, so the difficult part was finding the correct magneto. It comes out with two small bolts. I re-terminated the spark plug terminal to shorten the plug wire. The magneto comes with a few spare parts. Starts on first or second pull. Three bolts on the pull start assembly had to come out and the pull cord assembly and shroud had to be pulled. Very easy to do. I saved $240.00 on a new edger.

1. Diagnosed "not running" as a "no spark" problem
2. Ordered new armature magneto (AM) and spark plug boot from eReplacementParts.com
3. Read included directions
4. Put mower on workbench, disconnected spark plug cable, removed top cover and cleaned.
5. Removed spark plug. Removed 2 hex bolts and wire, lifted old AMout.
6. Rotated mower flywheel to opposite side per directions, attached wire to new AM, bolted into place per instructions, leaving big space between new AM and flywheel.
7. Again per instructions, rotated mower flywheel so that magnets face AM. Placed 0.010-inch thick card (included with AM) between AM and flywheel.
8. Loosened and re-tightened bolts. Now there is a 0.010-in gap between the AM and flywheel.
9. Reassembled. Put mower on floor and connected spark plug.
10. Gave a mighty pull and mowed my lawn.

Remove the cover. Install and adjust the new magneto. Replace cover.

If you suspect the mag and have not replaced the plug. Do that first.
Plugs wear out and can't be cleaned anymore.
When replacing the governor air vane, the screw made a dimple in the mag surface which caused it to bind.
I added a washer under the screw to stop this. That raised the assembly and caused it to catch on the starter shroud. I hammered that out to relieve.
The old air vane interfered with the new mag. I cut a notch in the air vane to clear.
Hardest part was repairing the governor carb springs. Small one is the idle. Bend opp end tab to adjust idle which that spring alone mounted. Large spring is high/low.
Adjust to raise speed when in position. Look for stretched spring coils. Fix by wrapping copper wire strands to join them together and make spring shorter.
This will increase tension and make engine speed higher if needed.

Replaced the magneto, the new coil did not require the points or condenser to get a spark to the plug.

Checked for spark.
No spark.
Replaced spark plug.
Checked kill switch for grounding out.
It was fine.
Still no spark.
Removed cover to get to the coil.
Removed coil clean coil and fly wheel and reassembled with .010 air space between coil and fly wheel.
Got spark and engine started, but only worked for a while.
Replaced the coil and wire. Works fine.

Replaced the old part with the new one.

I was glad to see installation instruction included with the part.