I got this 1986 Honda 350 fourtrax and it was running fine when it suddenly died on me. I immediately found out she's got no spark. no spark at all. I don't know much about ATV's; dirtbikes are my area. I've just done a quick eyeball check of the wiring, and it looks fine. I'm wondering what the problem could be. If it's a bad coil or a bad CDI. If so, where is the CDI and coil located on it? and does anyone know what the specifications are for diagnosing problems like this with a multimeter? thanks

 

Yes i think so but bear with me cause this is from memory. Your CDI is underneath the right inner front fender. First, release the lock, unplug it and plug it back in and retry. Still no fire? Disconnect your box again and do these checks on the harness side of the CDI coupler. First check the solid green wire for continuity to ground, it should have it. Next check your kill switch circuit, turn the key on and make sure the emergency kill switch is in the run condition. You should have an open circuit on the black\white to green pins. If you activate either switch it should have continuity. Next exciter coil, probe the black\red to green pins, you should have approx 100 - 400 ohms. Ignition coil primary side is black\yellow to green, you should see around .5 to 2.0 ohm. Pulse generator, either blue\yellow, blue\white or green\white or blue\white (sorry can't remember and Honda uses all these colors for the pulse on various machines) to green, should be 100 - 300 ohms. Next remove your restistor cap from your spark plug wire and probe the spark plug wire to ground, should be around 5 - 15 K ohms. If you see any iregularity, trace down that particular ciruit\component. Make sure you are doing your spark test with a NEW spark plug as plugs can foul, look ok but still not spark. If you have had any problem with your starter gears breaking in the near or distant past, I would expect the exciter coil on the stator as being the problem. The teeth can get caught in the flywheel and damage the stator windings.

 

Hey thanks.I think it might be exitor coil because since I got this atv, the starter has never worked. if you try and use the starter it makes a big hum noise and can't move anything. I gotta kick start it to get it going. Are most of these test are done on that 4 wire harness connector into the CDI and one on the 2 wire harness that goes into the CDI? I did all the tests you wrote and the wiring colours are different for some of them, I'm not getting any 100-300 ohms reading on one of the wires. I get the .5 to 2.0 and the 100-400 ohms one. Where is the excitor coil located?

 

Yes you can test the whole ignition at the cdi coupler, but there are connections other places. The exciter coil is the black\red wire. If you remove the seat and right sidecover, you will find the bullet type connecters that connect the engine (stator and pulse generator) to the harness. What color wires aren't you getting a reading on?

 

The 2 wire plugin has one wire that is black/red stripe, and the other wire is black/white stripe. The 4 wire plugin has a black/yellow stripe wire, a blue/ yellow stripe wire, a white/ red stripe wire, and a green/white stripe wire. The Green/white stripe is the ground... The blue/yellow stripe gives me a reading of 308 ohm. The black/yellow stripe give me .6 ohms. The ones I'm not sure are right is the white/red stripe one that gives me 4.6 ohms, or the black/red stripe one that gives me roughly 9 ohms. all the readings I get above are from having the black wire on the multimeter plugged into the green/white stripe ground.

 

I just took apart the cover over the starter gears and found a gear with about 8-12 teeth conveniently missing, I can imagine where they went. I think you might be right about the excitor coil being the problem. Maybe these nice missing teeth have done a number on it.

 

Yes, 9 ohms definitely indicates a problem. Sounds like a gear tooth is shorting the exciter windings against the flywheel or stator plate. I don't know for sure what the white\red wire is. I'm thinkin it's from the reverse sending unit.

 

Seth22 -
Just wondering if you ever found a stator for your bike per this post. I have had the exact same situation with my bike, but I'm on my third wrong stator. Did yours have the two excitor coils attached? If so, where did you find a new one?

Thanks

Jeff