Ignition coil burnout
- Thread starter Pony Joe
- Start date
Apologies for not replying yesterday, got busy and didn't see these posts til just now. Let's see, the engine is a Lifan 190 FD-B, 15hp. The coils don't look damaged but after each coil died I put a spark tester on it both times to confirm, no spark. Replace coil, spark is back, it just doesn't live long. I just used a light to check for voltage. Grounded one end and touched the other to the black wire, with the key on it lit up. I kept the lead on the wire and plugged it into the coil. As soon as the wire touches the coil terminal the light goes out. I haven't changed any wiring since we hooked it up the first time but something's not right now.
That wire should NEVER read 12 volts to GROUND.
It should be grounded with key off. With key off, you should read 12 volts from that wire to Positive side of battery, because the black wire is grounded to kill the engine. No matter what you do with the key switch, that black wire should not show 12 volts when one lead is on the black wire and the other lead is on ground or the negative side of the battery.
Please tell me you understand what I just stated, then please tell me if those statements are true or false on your project.
I will get specs so you can test the coils.
It should be grounded with key off. With key off, you should read 12 volts from that wire to Positive side of battery, because the black wire is grounded to kill the engine. No matter what you do with the key switch, that black wire should not show 12 volts when one lead is on the black wire and the other lead is on ground or the negative side of the battery.
Please tell me you understand what I just stated, then please tell me if those statements are true or false on your project.
I will get specs so you can test the coils.
I fully understand you. When the key is off it reads 12v from positive to wire. But when the key is on it reads 12v from negative to wire. I'm guessing maybe that's why the coil started dying? Just don't know why it was fine for 3 months and now its not. Don't know how its getting voltage to it. The number on the coil is 188F 27200 211216.
You need to trace every wire in your electrical system and verify that they match up to the schematic on page 1 of this thread. If you haven't already, pull the cover on your switch box and check the connections there. Where does that yellow wire on the negative battery post go?
Looks like battery + is going some place it shouldn't. Right now, I'm leaning torwards your rectifier went bad from a shock to the system in your previous thread, but that is just conjecture.
Isolate and simplify. Unplug from spark plug, unplug from starter solenoid (just the lead from the start switch). Unplug low oil sensor. Unplug all 4 rectifier bullet connectors. Put the neg. lead of your meter on battery neg. post and start testing for stray battery+ at all connections. Make sure it is where it's supposed to be and not where it shouldn't.
I'm also thinking that you will have to pull your flywheel and check your charging coils but first things first.
Looks like battery + is going some place it shouldn't. Right now, I'm leaning torwards your rectifier went bad from a shock to the system in your previous thread, but that is just conjecture.
Isolate and simplify. Unplug from spark plug, unplug from starter solenoid (just the lead from the start switch). Unplug low oil sensor. Unplug all 4 rectifier bullet connectors. Put the neg. lead of your meter on battery neg. post and start testing for stray battery+ at all connections. Make sure it is where it's supposed to be and not where it shouldn't.
I'm also thinking that you will have to pull your flywheel and check your charging coils but first things first.
Thanks for pitching in, @JimN , I also am thinking the rectifier looks like it is the only connection, but it should be grounded to the block.
HOWEVER...if it is not grounded, I wonder what that stray voltage would look like.
There should be a yellow wire with a stripe, grounded, probably to an engine bolt.
If that ground is not connected, the black wire at the coil MIGHT show 12 volts with the switch off.
HOWEVER...if it is not grounded, I wonder what that stray voltage would look like.
There should be a yellow wire with a stripe, grounded, probably to an engine bolt.
If that ground is not connected, the black wire at the coil MIGHT show 12 volts with the switch off.
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While searching for coil specs, I didn't have much luck. Some sites, which looked like Lifan, were shut down. What little troubleshooting info I found said things like...if sparking no replace coil...
I did find an aftermarket coil on Amazon. The small wire from the coil could be connected to a wire, run to the handlebar and grounded to kill the engine. This would isolate the ignition coil from the rest of the electrical system.
I did find an aftermarket coil on Amazon. The small wire from the coil could be connected to a wire, run to the handlebar and grounded to kill the engine. This would isolate the ignition coil from the rest of the electrical system.
While searching for coil specs, I didn't have much luck. Some sites, which looked like Lifan, were shut down. What little troubleshooting info I found said things like...if sparking no replace coil...
I did find an aftermarket coil on Amazon. The small wire from the coil could be connected to a wire, run to the handlebar and grounded to kill the engine. This would isolate the ignition coil from the rest of the electrical system.
I did find an aftermarket coil on Amazon. The small wire from the coil could be connected to a wire, run to the handlebar and grounded to kill the engine. This would isolate the ignition coil from the rest of the electrical system.
Probably, but I'm just spitballing at this point. I still think the problem is with the rectifier and/or charging coil. Until @Pony Joe can do some more troubleshooting I'm at an impass.
Maybe I'll just go work in the garden for a while, before I type something real stupid.
Think I got it. According to the schematic the big black wire coming from the rectifier should join a big black coming from the switch and then go to ground. The small black coil wire should join the small black coming from the oil sensor at a factory y and go to the key switch. The rectifier wire was plugged into the y where the oil sensor wire should have been, thus connecting the coil and the rectifier. I switched the two wires and tested for voltage at the coil end. No more voltage. Can't try it until my new coil comes in. What do you think?