Go Kart Engine Repair - Ignition System Diagnostics Part II

Ignition System Trouble Shooting.(check)
Last time we discussed how magnetic fields causeYes I checked it was ON! Also I removed the off wire
current to flow in wires. The current flow is thenfrom the switch near the engine. Still nothing. (check)
harnessed to make the spark plugs work.Pulled the spark plug out and tested for spark:
Now we will discuss how to trouble shoot this system.No Spark:
First of all the system consists of:The possible causes for no spark are:
-A flywheel with a magnetFaulty Spark Plug (ie short circuiting because of ash
-A magneto with a main coil and a switching coilcontaiminents, broken insulator, too much gas on plug)
-An On/Off wireOr a faulty ignition mechanism
-A spark plug and spark plug wire.Well I cleaned the plug well. Used a different plug...
That's it.Note: But you know what I should have done first? I
{In the olden days you had a switching circuit calledshould have taken the plug wire and tried it against the
points, but I will not bore you with that. I have severalengine. Well I tried that too: no spark.
old motors that have points. (If you are really interestedNot looking good here... What do we do next?
in points I will write an article about trouble shootingThis is where stuff starts coming apart.
those...but not today.)}Understand that the system involves the flywheel, so
So what's the problem?we need to access it and see if the flywheel is okay.
The problem is that I was riding my go kart... blew theBy "okay" I mean the following:
chain... made a massive clunk...engine still ran right up-Is there a magnet in it anymore?
until I shut it off. I replaced the chain and now it won't-Did it get damaged? (very unlikely) Check with
start.screwdriver: does it stick? (check, yes there is a
What do I do? Cry? Uh...No...magnet)
First off all look at the system. So the engine notThe next critical thing is to check the keyway. 8 times
running must be symptomatic ofout of 10 the key gets sheared. This can occur from
-No Gassudden stops of the engine. A sudden stop can occur
-Flooded (too much gas)from various reasons such as a broken chain grabbing
-No compressionhold of an activated clutch. An instantaneous shock
-No Sparkload can be introduced into the system.
-Switch is off!The other way an engine can be come jammed
So yes, I checked.. there is gas. (check!)suddenly is if the rod blew inside, or the engine ran out
The engine has nice resistance and compression (noof oil (seized up).
thrown rods, no loose valves, everything is tight...)Next time.... What happened to the ignition system?