No spark the magneto isnt firing - 1993 Harley Davidson XLH Sportster 883

Check for spark by taken cable off n touch cylinder..if no then magneto or a fuse is out..or bad connect etc. Fuel issue from carb..oldgas or airfilter

check the magneto. temperatures can affect the spark production if you have a bad magneto coil.

ok check the magneto if rusty clean with fine grit paper then try it if not then may be time to change the coil and magneto..

you can use a neon bulb voltage tester to check for spark
a magneto gets its spark from the collapse of the magnetic field that occurs when the points close
the magneto is comprised of two coils.
a primary and a secondary.
when the points are open the primary and secondary are one continuous circuit and generates a considerable magnetic field when the magnet passes the magneto.
when the points close the primary coil is shorted to ground.
this causes a very rapid collapse of the magnetic field in the magneto.
this field collapse can generate a very high voltage surge (the power for the spark)
this surge can exceed 12,000 volts or more and yes it is a bit painful

spark is simple start with ur plug if its not fouled, follow back wire and boot and check for hard spots or turn off all lights and turn over look for sparks. if it isnt this simple break out the voltage reg and start at the magneto check for current and compare to man. specs. it could be your point spacing or even magneto itself, if it is "mag" buy an aftermarket light kit it should come with mag, and all wires good if u screwed with the wiring harness.

It all depends on the model of engine. If it is a twin engine doesn't it have two magnetos.Very unusual for both to go bad It will depend on the type of ignition(points or solid state) The wire going to the magneto could be the kill switch (kills when grounded) Disconnect it and see if you get spark. IF so then it is in your safety/ignition circuit. If you replace magneto usually the gap is .008-.012

that could be from a short in the circutry even as simple as some debri build up around the blade brake magneto ground contact point that is grounding the magneto so spark can not continue to the plug could also be a fouled spark plug or could also be the magneto condenser attached to the magneto has burnt thus looseing capability to disperse the electrical energy to the spark plug, and worse case senario is the magneto is internally damaged from use also possably the magneto's air gap to the magnets on the flywheel is to exssesive for energy production hope this helps Steve

Hi Pry

The spark comes from the Magneto. Follow the spark plug wire and you will find the magneto at the end of it

The first thing you should check though, is the safety kill switch. There is a pressure switch in the seat that kills the engine in the event the driver falls off.

You need to be sitting on the mower to start it.

If the switch is ok and you still get no fire, it's the magneto.

Best regards,
Mike

Could be magneto bad, wire from magneto bad, ground on magneto bad, or the clearance between the flywheel and the magneto is rusted up if it was outside. Clean flywheel with sandpaper and set magneto gap using a match book flap.

Alright, remember that 2-Stroke motors are meant to do 2 things:
Break down, then Frustrate you.

So, here we go: (Electrical)

Rotor Magnets, Magneto (ignition coil), Spark Plug Wire, Spark Plug, Spark Plug Ground (Cylinder Head).

In that order!

Check your "fire" from the Magneto:

1. Check your Kill Switch. In other words, leave everything normal, and unhook it. Did she start? Kill Switch it is! Kill Switch/Wire comes from the Magneto (single wire/ground) to the Switch itself. So check that wire AT the Magneto (Is it loose and grounding out? Is the Kill Switch grounding you out where it is, because of crud, junk, or because it is touching the block when it is not supposed to?)

2. Check your Spark Plug Wire. Easy, unook it from the plug, stick your finger in, give it a crank (non-MultiMeter way). Did you get shocked? Then it ain't your Plug Wire and Magneto!

With a Multi-/Volt Meter, simply hook her up, and check for juice WHEN you pull the rope. If you got juice, it ain't your Plug Wire or Magneto!

Checking Spark the "normal" way: Grab the Plug with a pair of insulated pliers, hold the plug end against the cylinder head, and pull your rope. Any Spark? What color?

3. STILL no fire. It leaves: Magneto and Plug Wire.
Luckily, they are both in the same place! Tear your blower down, and check to see if the Magneto has slipped out of place (gap is WAY out), or if the Plug Wire has worn to the point it is grounding you out. While you are there, check your Kill Switch wire, to see if she is grounding you out then and there.

4. STILL no fire. That means: Magneto Failing, or Magneto JUNK.
Buy another one, replace it! (Or steal one from another junk Blower/Weedeater. These things are fairly standard, and easy!)
Or, Bad Plug Wire. Meaning she has failed out on you.
Wait......that means: Replace your Magneto! Lucky the things are built together right?