Is it the Coil?

[pdonoh]

My 1952 8N, which has been 100% reliable in the 12 years I've owned it, started yesterday completely normally. I was letting it warm up while I cleared my yard for mowing and it just stopped and would not restart. I live in the suburbs far from any tractor mechanics and admittedly, I'm not gifted in that area. I don't think its a fuel problem as there was no stumbling before it quit. My thought was to replace the coil and hope that's it. I will have to find a 6 volt one (Does NAPA still carry tractor parts). Meanwhile, the grass is still growing and I'm surrounded by soon-to-anger-my-lawn-is-the-best suburbanites.

 

[old]

My 1952 8N, which has been 100% reliable in the 12 years I've owned it, started yesterday completely normally. I was letting it warm up while I cleared my yard for mowing and it just stopped and would not restart. I live in the suburbs far from any tractor mechanics and admittedly, I'm not gifted in that area. I don't think its a fuel problem as there was no stumbling before it quit. My thought was to replace the coil and hope that's it. I will have to find a 6 volt one (Does NAPA still carry tractor parts). Meanwhile, the grass is still growing and I'm surrounded by soon-to-anger-my-lawn-is-the-best suburbanites.

ALWAYS trouble shoot then parts NEVER the other way around.
#1check that you have a good blue white spark at the center wire of the cap and at all 4 plugs that jump a 1/4 inch gap or more. Take an old plug and widen the gap to as close to a 1/4 inch as you can and use that to test.
#2 pull the carb drain plug and make sure you have a good steady flow of gas that fills a pint jar in under 2 minutes.
#3 pull the air cleaner tube off the carb and try to start it.
Do the test in the order I posted so as to lessen the chance of fire

 

[Jim L WA]

Sorry that happened, but they never act up at a convenient time.
First of all, you do have the fuel shut off valve open two full turns?
What old said is right on the money. If you don't have an old spark plug then just open the gap temporarily on one of the tractors plugs, or steal one from another small engine or other.
After performing those tests, come back here with the results.

 

[zuhnc]

If you forget to turn the fuel on, it will present the symptoms you describe. BTDT. Duh! zuhnc

 

[Btzj02]

Sorry that happened, but they never act up at a convenient time.
First of all, you do have the fuel shut off valve open two full turns?
What old said is right on the money. If you don't have an old spark plug then just open the gap temporarily on one of the tractors plugs, or steal one from another small engine or other.
After performing those tests, come back here with the results.

Don't forget that the fuel valve has a reserve just like an old motorcycle fuel valve. Two turns open is normal operating position. Turn valve all the way open to access the reserve of the fuel tank. Easy and quick to check!

 

[John P.]

If it comes to it, I just picked up a new 6-Volt coil for my 8N at NAPA. Echlin Part Number IC7.

 

[Bruce(VA)]

My 1952 8N, which has been 100% reliable in the 12 years I've owned it, started yesterday completely normally. I was letting it warm up while I cleared my yard for mowing and it just stopped and would not restart. I live in the suburbs far from any tractor mechanics and admittedly, I'm not gifted in that area. I don't think its a fuel problem as there was no stumbling before it quit. My thought was to replace the coil and hope that's it. I will have to find a 6 volt one (Does NAPA still carry tractor parts). Meanwhile, the grass is still growing and I'm surrounded by soon-to-anger-my-lawn-is-the-best suburbanites.

These tractors are amazingly simple machines; they are over 70 years old and were designed to be maintained by the operator.



Some basic troubleshooting skills and a few common tools will get them running. Randomly replacing parts doesn’t get you much.



But your friends will often get in the way of fixing your tractor. Rarely are guesses like "It's the coil" helpful. Jumping ahead to 'so-and-so said it could be whatever' or just replacing parts will waste your time and your money. We can make a long list of possible causes for the tractor not running and start picking our favorite to check out. Or, we can step back and recognize that the trick to fixing these tractors (or trouble shooting any piece of equipment) is to be systematic about it. You need to isolate the problem system by system, step by step and work from most likely to least likely and replace parts only when you confirm they are defective.



It takes three things for an engine to run: spark at the right time, compression, & gas/air in the right mixture. Compression is easy; check it with a gauge. But, you don't lose compression overnight, so if your tractor won't start, or suddenly cuts off, forget about compression for the moment, & concentrate on narrowing the problem to fuel or spark. If you don't do that, you are going to end up chasing your tail around that tractor & spending a boatload of money to fix what could easily be a loose wire or a clogged fuel tank vent. I offer this advice from personal experience because I am not a magician. I do not have the magical ability to simply diagnose the problem & go right to the fix. And I don’t like playing guessing games either. So, whenever my tractors stop, I confirm both spark & fuel then go from there.



I might not be capable of telling you why your tractor isn't running, but I sure can tell you how to figure it out for yourself.



Bottom line: as soon as the tractor stops running, not 5 minutes later, check for spark, fuel and battery voltage.



Does the tractor have a spark that will jump 1/4" in open air?*



Will the gas drain out of the carb bowl in a steady stream and fill a pint jar in less than 2 minutes?



What is the EXACT voltage at the battery? ( yes, you need a multimeter for that, not a worthless light)



How do I know this part is defective?



These are the questions you need answered before you attempt any repairs or buy a new part.



*If you don’t own a spark checker w/ an adjustable gap ( NOT a light) buy one. In the meantime, an old spark plug w/ the gap opened to at least ¼” will work. Ground it to a rust & paint free spot on the engine turn the key on & look for a spark.



Amazon.com: 【The Best Deal】OriGlam Spark Plug Tester, Adjustable Ignition System Coil Tester, Coil-on Plug Ignition Spark Circuit Tester, Autos Diagnostic Test Tool : Automotive

 

[Eman85]

Don't guess, don't replace parts without diagnosing. First step for me if the engine turns over OK would be to check spark. I've had to get mine started in a field before and it's always turned out to be a spark problem, usually a quick filing of the points and back to running.

 

[zuhnc]

As to shotgunning parts, you might spend $500.00 only to find a $0.30 crimp connector is corroded. @Bruce (VA) is correct in troubleshooting systems - divide and conquer when doing so. zuhnc