M has no spark

[Mark Poss]

I have a 1950 M that has been converted to 12 volt. Looks to still have the 6 volt coil with the resistor wired next to it. I have spark at the points. I cleaned up all of the contacts on the cap and put it back on but nothing coming through. Im not very good with electrical. Tractor has a corn picker mounted on it so its a real PITA to work on. I had it running a month ago. Id like to get it running and take the picker off and convert to electronic ignition. Thanks for any advice, Mark

 

[NY 986]

Probably getting way ahead of myself as usual but I'll ask as to what make and model picker and if you plan to keep it.

 

[old]

The cap could be bad and grounding out the spark or the rotor could be bad. One way to check if the cap is bad but you will only do it once is grab the cap and try to start it. If you get zapped it is bad but it will not feel good

 

[Janicholson]

Use a wooden spring type clothes pin to hold the coil wire so that the end that was in the center of the cap is 1/4 inch away from the block. In neutral and brakes locked (or wheels chocked) see if spark jumps to the block. If yes, the issue is in the rotor or cap. If not the coil may be toast. Jim

 

[NY 986]

Thinking about this for a few minutes now. Do you have a tester to know how much current you are getting along the circuit? With the plug wire end 3/8 of an inch away from the spark plug and turning the engine over with the ignition button in the on position you are not seeing a spark jump that gap? The cap installed correctly relative to the firing order and following the firing order per the sequence shown on the cylinder head?

 

[DanielW]

You say you have 'spark' at the points. If it truly is a visible spark at the points - that's not good. That's typically a sign of a bad condenser, which causes the points to arc, and subsequently can burn out the points so you're not getting proper/consistent spark.

I'd start with a new condenser, clean up the points with a points file, re-set points gap, and try from there. Some folks say you shouldn't use points files because it takes off the coating, but if your points have been arcing/sparking they're at the state where it's not going to hurt. And people have been using points files for years.

Sounds like you have voltage to/through the coil, so if that doesn't do it, check your dizzy cap - make sure the springy contact tab is making contact and the graphite tab that contacts the rotor is good. Lots more it could be, but I'd start with that. Condensers go bad all the time, causing points to foul up or get pitted.

I would definitely get it running top notch before the electronic conversion. Lots of folks with spark/timing issues change to electronic hoping that will fix their issue, then it still doesn't work, and you've just added one more variable to test. Others may disagree, but I've changed my tune on electronic ignition kits. I used to be all for them and can see the appeal of being able to stick it in and forget about it. But you often see posts on here of, 'How to test my electronic ignition kit', or similar, so I'm not sure that they're always a 'fit and forget' scenario.

Most of my tractors are still points/condensers. I've only had one case of them failing, and that was on a set of points/condenser that hadn't been changed (or even touched) in my lifetime. On the other hand, I have two tractors and one old Fiat car that has been converted to Pertronix ignitions, and the electronic ignition module failed in the Fiat after a few years. So that's about 1 out of 17 points/condensers that have ever failed on me, and 1 out of 3 electronic ignitions that have failed.

 

[John T]

Here's my Troubleshooting Procedure in case of no spark, check it out:



http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Ignition Troubleshooting

 

[560Dennis]

Had trouble with a cap

 

[Mark Poss]

I posted this 2 months ago. Since then I have got it running and picked corn. No idea why it is showing up again. Thanks for all the replies anyway, Mark

 

[used red MN]

I posted this 2 months ago. Since then I have got it running and picked corn. No idea why it is showing up again. Thanks for all the replies anyway, Mark

Mark, it is the new forum format. No different than Modern acted before when a reply was made it brings the topic to the top of the page. DanielW replied after the software switch, so your topic was brought forward. There is a possibility that he saw this in the “Similar Topics” that the format now places after each discussion topic where the software “AI” places past subjects that are similar. When viewing you have to pay attention to the dates or you find yourself replying to old posts. Another forum I am on did this same thing, but they have a warning that pops up informing you that you are replying to an old thread. Not sure if this forum is doing that. If it does not I will recommend this to the moderators to add such a warning.

 

[John M]

Mark, it is the new forum format. No different than Modern acted before when a reply was made it brings the topic to the top of the page. DanielW replied after the software switch, so your topic was brought forward. There is a possibility that he saw this in the “Similar Topics” that the format now places after each discussion topic where the software “AI” places past subjects that are similar. When viewing you have to pay attention to the dates or you find yourself replying to old posts. Another forum I am on did this same thing, but they have a warning that pops up informing you that you are replying to an old thread. Not sure if this forum is doing that. If it does not I will recommend this to the moderators to add such a warning.

No, it was there before the switch. Plus, look at the dates. The switch was yesterday. Whe nI saw it on the old format, I thought it was a new post.

 

[used red MN]

No, it was there before the switch. Plus, look at the dates. The switch was yesterday. Whe nI saw it on the old format, I thought it was a new post.

Looking closer I see it was 560Dennis that made the reply. No problem really, just do not want the new software updating post with a reason.