No spark!

[checkmate243]

I have lost spark on my JD 316 p218g. I think the ignition coil went out. I would like to check it out before I spend $110.00 on the replacement coil. Dose anyone have a electrical schematic and a spec for output on the coil itself? Any help would be great....Thanks Patrick

 

[dg60ford]

I'm not sure what year your JD is but I'm asuming it has an Onan engine with electronic ignition instead of points. In my experience it is rare for the coil to go out on these and 9 times out of 10 it was a wiring issue, or a bad ignition switch.

 

[checkmate243]

dg60ford- My JD is a 1989 and yes it has electronic ignition. Thanks for the info. I think I need a JD service manual to find the spec. I will check the wiring out too. Last summer it would cut out after warming up? Cool downs and starts up again. Now I have nothing at the spark plug. The pto is not engaged. I'm learning JD dose not like downloading spec out of there manuals. opps!

 

[checkmate243]

I went ahead and replace the ignition coil and the JD ran great for about 30 mins. No spark again. Waited about an hour started up again ran 15 min lost spark again????????

 

[ToadHill]

I'd hook up the old coil and see if you get the same 15 minute run time. It could well be that something in the electronic ignition is failing when it heats up, most likely something in the circut board.

 

[checkmate243]

The old coil had nothing left in it(no sprark at all). This was the reason I replaced it. This is how the whole problem started last season with the old coil. Work for awhile than nothing. Wait a while, it would start up but the spark was pretty yellow(weak). Can I fix the board or do I have to replace it? Thanks Toadhill for the reply.....

 

[ToadHill]

To fix the board you'd have to have the equipment to test each circut. I'd take it to someone who is equipped to test it.

 

[checkmate243]

Where is the electronic ignition located? I think the part number is HE166-0785. What dose it in tale to replace? Thanks again..

 

[onanparts.com]

Where is the electronic ignition located? I think the part number is HE166-0785. What dose it in tale to replace? Thanks again..

The electronic ignition module is located behind the flywheel and mounted to the timing cover just under the crankshaft.

Troubleshooting ignition module.

Connect a Jumper lead directly from the positive battery terminal to the positive (+) coil terminal (smaller diameter of the two threaded posts) Crank engine over while watching for spark, If spark occurs, the problem is in the low oil pressure cut out switch (if equipped) or related wiring, the lubricating system (low oil pressure), or in the other circuitry bringing voltage to the coil. If no spark occurs, try the next step.


Connect positive side of voltmeter to negative (-) coil terminal (larger diameter of the two threaded posts) and negative side of voltmeter to engine ground. Turn key on and or leave the jumper connected from the + battery terminal to the + coil terminal and rotate flywheel slowly by hand while observing voltmeter. Voltage should switch between battery voltage and 1-1.5 for each revolution. If voltage does not switch properly, replace ignition module.

Never put B+ lead to the coil negative terminal. This will cause failure of the electronic ignition module!

If ignition module is being replaced, be sure to connect red lead from new ignition module to + terminal of ignition coil and black lead to - terminal of coil.

TJ

 

[Treemonkey1000]

I am not that familiar with that ignition but I am familiar with electronics. I would suspect the electronic module after your still having problems. The board can have a crack in it and cause problems after heating up. Or poor solder connections will do the same thing. There could be a bad wire connection in the plug. Oxidation will cause problems in wire crimps to give you those kinds of problems.. At least that would be my lame input.

 

[checkmate243]

Treemonkey1000,
Any input is help full. I will check run test onanparts.com gave me and go from there.
onanparts.com,
Thanks for the spec on test the electronic ignition module. I like your web site and saved to favorites. I知 sure I will need it!

Patrick

 

[Ken Cunningham]

Have you put a new plut in? I had a tiller once upon a time that would run fine until it got hot, that thing just about drove me crazy. Turned out to be a bad spark plug, it would work fine when it cooled off but quit when it got hot.

 

[johnk]

I had a mouse strip the insulation of an ignition wire and it would fire up when it wanted to and quit when it wanted to. It gave a dead short tomthe frame and the vibrations of trying to start sometimes moved it far enough awat y from the frame to start. Darn mice..It's a possibility because I also did everything in my power before I located the wire..Good luck.

 

[imneo88]

This message is for Onanparts.com and may help both myself and the original poster..
I found my bad keyswitch was only part of the problem with my ignition system.

My ignition system will only spark when the voltage at the coil is 12V or higher, which means that while cranking the motor it doesn't have any spark because the starter is draining the system below the 12 Volt level..

I have already eliminated the keyswitch, oil pressure sensor, spark plugs, and all of MTD's kill switches as possible causes which only leaves the ignition coil and the HEI unit under the flywheel. The HEI unit test that you specified above gave a reading of 0.9 Volts once per every revolution of the flywheel.. But are there other tests that I can do to test the ignition coil and HEI resistance that might tell me which one is the culprit..

Thanks,

Kevin B. Payne
"New Project = Big Headache"