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8N starting problems

Ted Fisher I have had trouble starting my 8N with front mount distributor for several weeks. Once it starts it runs great but the starting problem has gotten worse and now I can't get it started at all. Here is what I have done: Cleaned carb, set float, gas flows through carb at 1 pint in 2 minutes. New points, condenser. Before we set the points we had a spark jump a 3/16 gap on 2 plugs only. After points there is no spark. I am pretty sure we did everything right in the distributor, we have checked all connections. I am thinking the coil may be at fault, even though it is only a few years old. We do use this tractor a lot, go through about a tank of gas weekly.
Any ideas? Thanks, Ted


Bob G If you lost spark after changing the points, I would make sure the points are making good contact when closed. Also I would chek the gap and contact on all 4 lobes. check for slop in the shaft also, side to side play. the bushings do wear.
Do you have a 6 volt set up or has it vbeen changed to 12 volts? You have to match the coil and resistance in the ignition system to what you have. Do you have good current flow through the ignition switch. might make a jumper and go around the switch as a check. They do go bad.
The coil could be bad, but I would not just replace it with out checking everything out. If you have an ohm meter you could check it for continuity.
Bottom line you have to have current flow from battery thru ignition switch thru ballast restistor thru coil and then thru points then to gound.
Good luck

Ted Fisher I bypassed the ignition switch, no change. Checked resistance on coil. I am not sure how to read it but I think the scale was 10k. The coil was off the charts. Is that good or bad? Its ok, you can laugh! Anyway I checked for spark again with a regular gap, not the 3/16. Out of all the plugs I got one spark, meaning just one, not continuos from one plug.
I did not take the distributor apart again, but two hours ago when we put the points in I did think they met pretty square on. Checked the gap on all four lobes and it was the same. There is a small amount of play in the shaft. It doesn't seem like a lot to me but I am not sure what is acceptable.
This 8N is a 6 volt. Also the engine was rebuilt a year ago and compression is good.

Thanks again. Ted

Bob G I think the coil should only read a 1.5 ohms. That is read from the top screw to the pig tail spring on bottom so yo have to take it off. If you were checking it with the coil installed from top screw to ground, it the points were open you would read infinate restiance. Just like tehe probles not touching anything. quite often the pig tail does not make contact and will result in not spark.
Did you check for voltage to top of coil? should be almost battery voltage with points open and next to nothing with points closed.
Good luck

Ted Fisher Bob,
coil reads between 7 and 8 ohms when removed from the tractor.
Voltage at the coil is almost 6 points open and 1 with points closed.
I was careful to get the pigtail in the right place. I have also noticed that it is sometimes a problem.
Still no spark.
Thanks

Bob G The 7 to 8 ohms sounds to high, but I don't know what it would do. the rest souds good. If you could test a new coil that would give you an idea of what dit should be. It may be your problem.
Tim I have 1949 8N tractor, the problem I am having is the tractor wil crank and run for about 5 minutes then it will stop, it takes sevearl minutes or eben a hour before I can re start it, I have checked my case and changes the full filter, please advise, thanks.
mark sr Tim, it sounds like your coil is failing.
Bob G I would make ajumper around the ignition switch before I replaced the coil. Cheaper!! Did you check for fuel flow out the bottom of the carb bowl? should fill a pint jar in 2 to 3 minutes.
Bob G My last post was for Tim, Tim, you are better off starting your own thread rather than posting a different question on someone elses post. Easier to keep track of.
Jim Loveridge Ted, before you buy a new coil, try putting the old condenser back in. The new one might be bad.
Ted Fisher So I got a great spark after replacing the coil. However we had to pull it with the truck to get it started. It ran fine for half an hour, but as before does not want to restart, even after sitting for five minutes.
I have the carb adjusted at 2 turns out.
I'm at a loss at this point. any ideas?
Thanks for your time!

Bob G Do you have the ballast resistor on the back side of the dash installed and hooked up?
gary what would be the point settings for the 8n-2n-9n 4 cly its my friends tractor and im just trying to help him get it going if anyone knows please help thank you
mark sr Gary the gap on a NAA is .024-.026, I would assume it's the same for the earlier Ns. Bob or one of the others can tell you for sure.
ted Fisher Yes, Bob, I do have the resistor hooked up. The voltage at the coil reads 6 volts. Does it seem like it would have to be carb related since I have good spark? Thanks
Bob G Remove the bolt ffrom the bottom of the carba nd check for fuel flow. yu shuld get a pint in 2 to 3 minutes. That will check the three filters in the system plus check the float needle in carb.
Bob G 9n,2n abd early 8n is 0.015" These have the front mounted distributors.

Late 8n with distributor on the side is 0.025"

It is always beter to start a new topic rather than hijacking someones elses question.

gary thank you for the help guys i am greatful for your help
Jim Loveridge Bob, if you re-read Ted's initial post, you will see that he has checked for fuel flow through the carb. Ted, the ballest resister may be at fault. What voltage reading are you getting at the coil when the tractor shuts down after the five minuites. Also you might try checking and cleaning all the wiring connections involved.
ted Fisher Thanks guys. I am leaving town for a few days. When I get back I will let you know what I find.
gary so about my friends tractor he said it sat for two years because one of the workers had jumped it with a 12 volt charger instead of a 6 volt what kind of damage could have happend and where should i start frist with this problem it would be great if anyone has awnsers or help
gary about my friends trator he said it sat for two years because someone that worked for him jumped it with a 12 volt instead of 6 volt what kind of damage could that have on the ele system and where should i start frist
Bob G I would first find out if the engine will trun over or not. might be stuck.

If you an find out which tractor it is then we can ofer more help.

http://oldfordtractors.com/

check out this site for info on how to id it.
Good luck

ted Fisher Thanks for the help guys. I finally got new replaced the resistor and it started right away. Ted


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