No Spark

[Farmer Frank]

I've been troubleshooting now for 6 weeks and I'm about to sell the darn thing. Sorry... really frustrated.

49 8N with 6 volt system. I've checked fuel and feel confident it's not a fuel problem... gas is flowing from the bottom of the carb pretty fast. Now I have issues with the electrical system. I had it running over the weekend twice. The first time it ran for about 10 minutes... had it around the yard, went to turn down the idle and it died. Couldn't start it right away. Got it running again and let it run for another 10 minutes. Killed it and it would not start again. Now I can't even get it to fire. Changed plugs and wires (one was frayed), replaced distributer cap (had a lot of build up on the brass points), cleaned points with dollar bill. I did not replace the roter. When I replaced the cap and wires last night, I don't even have spark now. Could it be the roter? Should I replace that? I've done most everything listed on the 'boxed' responses on the message boards and starting to get pretty frustrated. Any ideas on next steps? Any one in the Central Illinois area willing to come over and look at it? Thanks all! I love my 8N but just frustrated!

 

[HCooke]

jump directly from battery to coil and try to start. If it runs your problem is between the bat and the coil. If no spark still, then problem is between the top of the coil and the rotar. Most likely place is the spring on bottom of the coil is not contacting the concave screw.

 

[Farmer Frank]

can you give me a kindergarden explanation on how to do that? sorry... I wish I was more of a mechanic! thanks!

 

[Bruce (VA)]

I recognize the name & the problem as well as the questions I asked you on May 4th:


"You also said " Checked points and distributer and they appear okay. " What does that mean? Did you check the point gap & do a continuity check while the distributor was off the tractor?

What voltage do you have at the top of the coil? "

If you replied to my questions, I apologize for missing the response.

So, did you pull the distributor, check the point gap & do a continuity check? If not, then that explains why you are still having problems a month later.
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[souNdguy]

could it be the rotor? why even have it in line for the first test?

use the wire from the coil secondary tower and hold it near the block to check spark.

as for the points.. use an ohm meter or a test lamp inline with the primary to see if the points are opening and closing. also.. use a jumper wire from the battery to the coil primary to rule out upstream wireing.

soundguy

 

[Farmer Frank]

Thanks Bruce for you help. What is a continuity check? How do I do that? Maybe that was part of your response. Some of the responses are too technical for me... which tells me I probably shouldn't be trying to trouble shoot this, but I had paying for something I can learn to do. Thanks!

 

[Dell (WA)]

Frank......while we love giving advice, you haffta beable to apply it. Suggest you squander $25 (cheap) for I&T FO-4 manual. It even has pictures for the reading challenged. It shows you everything we have told you about. Isn't that amazing??? ......respectfully, Dell

 

[Bruce (VA)]

Too technical? No, not really. These tractors were designed for guys who plowed w/ mules. If you can operate a PC, you can keep a 60 year old tractor running.

Assuming that the bushings & advance weights are ok, & that you have correct voltage to the coil, (check that before you do anything else) the most common electrical failure (no spark, weak spark) points on the frontmount are:

1. The insulator under the brass concave head screw.

2. The insulator at the end of the points where the copper strip attaches.

3. The copper strip is broken or grounded to the plate.

4. The condenser wire grounding.

5. The pigtail/tab not making contact.

6. Incorrect positioning of the spring clip on the plate causing the pigtail to ground.

7. Incorrect seating of the coil on the distributor due to a loose bail or no gasket; the coil must not move at all.

8. Water/moisture inside the cap due to gasket failure or the absence of a gasket.

9. Dirty/corroded/incorrectly gapped points

10. Burned rotor, cracked/carbon tracked cap.

Pull the distributor & do a continuity check.

First, make sure your meter/light works (don't ask....)

Next, dress the points by running a piece of card stock or brown paper bag through them. New points sometimes have an anti-corrosive dielectric coating on them & old points can corrode or pick up grease from a dirty feeler gauge or excessive cam lubricant. Then, check the gap at .015 on all 4 lobes.

Now, follow these steps:

1. Coil off, cap off, points open. One probe on the brass screw & the other on both sides of the open points. On the side closest to the cam, you should have continuity. Not on the other side! If you do, you will also have continuity everywhere because the points are grounded.

2. Coil off, cap off, points open. One probe on the brass screw & the other anywhere on the body of the distributor. You should have no continuity! Now, rotate the tang on the distributor....as the points open & close, you have continuity (closed) and lose it when they open.

3. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other on the cam side of the open points. You should have continuity!

4. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other anywhere on the body of the distributor. You should have no continuity!


At this point, I just put the distributor, coil & cap all back on the tractor as a unit (it’s easier to do this from the left side). The reason I do this is because it is real easy to get the cap or coil mis-aligned trying to put it back together one piece at a time & the result is something gets broken or you get a ‘no spark’ problem.

Post back w/ results & any other questions.
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[36 Coupe]

Friends and I got a Model A for doing farm work.Oldest was 12 or 13.We replaced a cracked head, got the distributor in backward.My dad helped but made sure we did most of the work.We asked many questions,got an owners manual from the Ford garage.To this day I cant understand why grown men cant start a Ford tractor.Dad showed us to read the ammeter to check the points and reading the charge rate.

 

[Bruce (VA)]

" To this day I cant understand why grown men cant start a Ford tractor."

Probably because most grown men these days never had a need, interest or reason to do anything on an engine like we did as kids. My 31 yr old SIL, w/ graduate degree in engineering & a job at the nuke plant, is clueless when it comes to tillers, lawn mowers, etc.....but I haven't installed a bit of hardware or software on a PC since he & the daughter got married!

Face it, our fathers probably thought we were equally clueless because we couldn't cultivate the tobacco w/ a mule.

 

[36 Coupe]

Still dont understand the blank spots in peoples knowledge.I grew up farming, working on cars,radios and tv sets.Built my own house,worked as a carpenter,mill hand in textile mills, trucking lumber.I can still go into my woods, bring home logs and saw them into lumber.Dry the wood,mill it into trim and furniture.Doctor horses and cattle.Grow vegetables, bring in the hay, put up firewood.Ive sharpened tools and saws, fixed small engines.I can run a metal lathe.Computers are a bit much but my grandaughter sets me right.Ive worked the land with horses, cooked in restaurant kitchens.Fire man for 35 years.Always repaired my guns, hand loaded ammo.No blank pages in this old mans book.So when some one cant get a spark out of his tractor I say why not.

 

[Anonymous-0]

I had similar to this problem with my 9n, I don't know if its the same but i had water in my distributor. Radiator overheated and there was no hose to drain the excess. So it hit the fan and got in the distributor. Hope that helps.

 

[Bruce (VA)]

Did you replace the gaskets?
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