414-8 - No Spark

[Jaybo 8]

I sort of happened upon a 414-8. Put new battery in and replaced the key switch. It turns over but it seems as though I dont have spark.

 

Put starter fluid into the spark plug hole and kicked it over but got nothing. I am new to this tractor and am excited to get it going, but need some guidance.

 

Where is a good place to start? Are there posts here that I have overlooked that might help?

[Sparky-(Admin) 23,111]

Welcome to Red Square! 
   Is your 14 a Magnum or K series? Magnum has a magneto under the shroud. The K series  has a coil, condenser and points. 
 

[oliver2-44 10,679]

As Sparky asked, a little more info on the engine model would help. Pictures would also help.

May I suggest you use gas in a squirt bottle, carb clearer, or brake clean as a starting fluid. 

Diesel starting fluid is too explosive for the small engines and can damage them. 

  

[jsp_333 280]

Sure sounds like you don't have spark but...  Start with a known good plug  then ground it to the engine, reconnect the spark plug wire and try turning the engine over.  If you have spark then you'll see spark from the plug.   If not then you'll have to work back from there.   Good luck and welcome to RS

[Jaybo 8]

Good afternoon. Thanks for the welcome!

It is a 414-8 Magnum. The engine model is M14S.

 

I did get a new plug, but have not tried that yet. I will try to lay the plug on the block and crank it to see if that produces anything. I will also get some pics and post as well.

 

Thanks again!

Edited June 29 by Jaybo

[Sparky-(Admin) 23,111]

Or get one of these from Harbor Frieght..in line spark checker. 
 

[gwest_ca-(File Mod) 11,439]

Make sure your pto is OFF. One half of that pto switch controls the the ignition by opening the magneto wire allowing the ignition to work when the pto is OFF. Try sitting in the seat when starting as that switch also opens the magneto wire.

When the magneto wire is grounded that shuts off the ignition. Magnetos are self-powered so never apply power to them as that will release the magic smoke.

 

[kpinnc 14,569]

1 minute ago, gwest_ca said:

Make sure your pto is OFF.

 

Agreed. On a Magnum powered Wheel horse: sit on the seat, make sure the PTO is disengaged, push in the clutch. 

[953 nut 59,735]

7 hours ago, Jaybo said:

starter fluid

Please don't use starter fluid, it can harm a small engine.

Is this a new problem that wasn't there when you got it from the previous owner?

Once you have checked to see if you have spark we can begin to eliminate possible problems. If there is a good strong spark we will take a look at the fuel delivery system. If you don't have spark we will walk you through the wiring.

Since the starter turns over from the key switch it is unlikely that any of the safety switches are causing the problem. 

 

Edited June 29 by 953 nut

[Jaybo 8]

Good morning. I didn't know that starter fluid was that bad. I will use an alternative that was recommend.

 

I sat in the seat, pushed in the clutch, pushed in on the brake, using the new plug, and still no spark. I am pretty sure that the PTO handle was disengaged as well. I will try to verify that again this AM.

 

The tractor did start and run but that was early last year (2024). It has been stored in the barn until about 4 weeks ago, it has been sitting in the elements.

I replaced the starter switch a few days ago. I used this (Stens 430-512 Starter Switch Replaces Toro 103990 Power King 03-2028 AYP 2683R Lesco 050102) from amazon. https://www.amazon.com/dp/B0015MJWAG?ref=ppx_yo2ov_dt_b_fed_asin_title

 

I have noticed that there is a wire with a terminal on the end, but I dont see where it goes. I will try to get a pic of that.

[pfrederi 18,630]

14 minutes ago, Jaybo said:

Good morning. I didn't know that starter fluid was that bad. I will use an alternative that was recommend.

 

I sat in the seat, pushed in the clutch, pushed in on the brake, using the new plug, and still no spark. I am pretty sure that the PTO handle was disengaged as well. I will try to verify that again this AM.

 

The tractor did start and run but that was early last year (2024). It has been stored in the barn until about 4 weeks ago, it has been sitting in the elements.

I replaced the starter switch a few days ago. I used this (Stens 430-512 Starter Switch Replaces Toro 103990 Power King 03-2028 AYP 2683R Lesco 050102) from amazon. https://www.amazon.com/dp/B0015MJWAG?ref=ppx_yo2ov_dt_b_fed_asin_title

 

I have noticed that there is a wire with a terminal on the end, but I dont see where it goes. I will try to get a pic of that.

  YOU have the wrong ignition switch.  It is for a K series battery points ignition.

 

If you used it on your magnum yo may have destroyed the magneto.  You need a switch with an "M" terminal not an "I"

[jsp_333 280]

16 hours ago, Sparky said:

Or get one of these from Harbor Frieght..in line spark checker. 

 

 

Didn't know that even existed. THX. Just ordered one.

[Jaybo 8]

Dang, OK. I hope it isnt ruined.

 

Will this switch work?

 

From amazon

https://www.amazon.com/dp/B0015MJWAG?ref=ppx_yo2ov_dt_b_fed_asin_title

 

[Jaybo 8]

4 hours ago, pfrederi said:

  YOU have the wrong ignition switch.  It is for a K series battery points ignition.

 

If you used it on your magnum yo may have destroyed the magneto.  You need a switch with an "M" terminal not an "I"

Dang, ok I hope it isnt ruined. Will this one work? From Amazon.

https://www.amazon.com/dp/B0015MJWAG?ref=ppx_yo2ov_dt_b_fed_asin_title

 

[Jaybo 8]

Regarding the switch, can anyone tell me what this additional wire is for? Seems like it should go to the switch.

 

 

IMG_7192.HEIC

Edited June 30 by Jaybo
learning.

[Jaybo 8]

Or is this perhaps the right key switch?

 

I found a reference to that part number in this link:

 

 

https://www.amazon.com/TCINDRR-Ignition-Compatible-103991-111215/dp/B0CZ95XCRV/ref=sr_1_3?crid=39ESQ6GEET8R9&dib=eyJ2IjoiMSJ9.FsR7gU3NGzAdp3v53KW0yOF8KP2YJa83tjyjTwYHJd7yQqCcxyP4iDRWV3ib6SBRwUt0YXYxUG5dp4ljhK8YwsuD0tJvgGEpePdNjyo58tyZWlciUa-OYecuoBIC1RDIV4oIK1sNraSvUIxXVoXDts3YR6PoS8BCfhpezqPtxc5sHHpECWM9BqKVvwj2b6P142MRnnuPWzwFlSum6WOteW_n7A1d2kz9qK1tgpzbYT8.ChWOcMyaOai1gJtFWgrC92fnc_AZjOgu4V8Tl94unFg&dib_tag=se&keywords=103991+ignition+switch&qid=1751305294&sprefix=103991%2Caps%2C138&sr=8-3

Edited June 30 by Jaybo

[gwest_ca-(File Mod) 11,439]

The 6th wire to the side is for a ground to make sure the body of the switch is grounded. 103991 is the correct switch. As you have seen they all look alike but inside they function differently.

[953 nut 59,735]

6 hours ago, Jaybo said:

Dang, ok I hope it isnt ruined.

Unfortunately the magneto was most likely harmed. Here is information from a post I did a few years ago. I wish the manufacturers would have made the configuration on these switches different enough that insolents like this couldn't happen.

 

Garry @gwest_ca, I had never taken the time to place the two switching layouts side by side. Very interesting to a wiring geek like me. 

 

I took your information and carried it out to see what would happen if a 103991 (Magneto) switch was placed in a Battery Ignition tractor. With the exception of a frustrated person wondering why nothin works the outcome would be rather harmless.

In the OFF position the R and A terminals would be connected Ground, no big deal.

In the RUN position the I, A and R terminals would be connected, nothing would happen but no harm would come of it.

In the START position the S an I terminals would be connected, once again nothing would happen but no harm would come of it.

 

On the other hand, if this situation were turned around and the 102990 (Battery Ignition) switch were placed in a Magneto tractor things get a bit more interesting and a whole lot more expensive.

In the OFF position none of the terminals are connected and all is well.

In the RUN position the B, R, A and M terminals are connected and magic smoke will be released from the Magneto.

In the START position the B, A, S and M terminals will be connected and the engine will turn over but there will be no spark because the magneto already is toast.

[Handy Don 13,970]

18 hours ago, 953 nut said:

I had never taken the time to place the two switching layouts side by side. Very interesting to a wiring geek like me. 

This is an excellent post.

Is it worth potentially clouding the issue to follow this diagram giving an explanation of WHY the magneto being fed a mere 12 volts goes kablooey?

 

The simple explanation I always start with is below. If I get a blank stare, I just stop talking but if there are questions, I”ll go deeper. Feel free to ignore me and supply your own explanation or none! That said, I think the final version of this post ought to be pinned to the top of the electricals. 

 

Why the smoke?

The magneto generates a very tiny voltage pulse in its primary winding when a flywheel magnet whizzes past. Its secondary winding takes that tiny voltage and hugely amplifies it to eventually make a spark at the plug. Grounding the primary winding prevents the tiny voltage from getting to the secondary winding, hence no sparks. The wire to the M terminal on the correct switch does the grounding to stop the engine.

 

On the wrong switch that M terminal magneto wire is fatally connected to the Ignition terminal. Moving that switch to the RUN position, instead of grounding the winding or sending a tiny pulse, sends a continuous hefty 12 volts down that wire. The magneto’s secondary winding tries to hugely amplify the 12 volts and instantly overloads, “smoking” the magneto.

Edited July 1 by Handy Don

[Jaybo 8]

It is hard to express my gratitude for the help from this community. Thank you!

 

Given my mistake with the switch, it seems that I need to go ahead and replace the magneto.

 

It seems that this is the right part given the description.

From Amazon:

https://www.amazon.com/Realman-4758401-4758402-4758403S-4758404/dp/B09QG8B9Q9

 

Realman 4758401 4758402 4758403S 4758404 Ignition Coil Magneto for Kohler M10 M12 M14 M16 Magnum Series Engines

[Jaybo 8]

It runs!

 

I replaced the switch with the correct one. I also replaced the spark plug and it kicked over and is running great! I am not sure how I got luck that the magneto did not get ruined, but it starts and runs like a champ!

[Jaybo 8]

On 6/30/2025 at 1:57 PM, gwest_ca said:

The 6th wire to the side is for a ground to make sure the body of the switch is grounded. 103991 is the correct switch. As you have seen they all look alike but inside they function differently.

I replaced the switch and the spark plug and it runs great. Thanks for the help!