8N 6v front mount distributor-Problem no spark at plugs

joe northrup

New User
Tractor has ran fine, go out pull choke and it turns over one time and cranks.Parked it a month ago running fine, shut it off, took the key out with it running fine. Went out today and got no spark. Is it gremlins paying me a visit or what?
 
Also I have fire where the wire comes into the top of the coil. I have no idea from this point what to look for or how to look for it. Just strange how it worked fine then it quit.
 
So I have the distributor and coil still togather on the table in front of me. How do I verify that all is working in dist.
Thanks
 
Assuming that the bushings & advance weights are ok, & that you have correct voltage to the coil, 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.

Unless the coil is cracked or shows a dead short, chances are it's fine; square coils rarely fail cold. 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.
distributorinsulator.jpg

50 Tips
 
The trouble with points is they need a lot of maintenance. Points can be good but get a haze or film on them that sliding a piece of grocery bag through them will correct. Simple as that.
Not too much to ask from an old rig like an N.
You could also convert the tractor to 12V, add electronic ignition and probably not have to mess with your electrics ONCE between battery changes = about 4-5 years.
I'd be willing to do the grocery bag thing on a side mount. But on a front mount?
Why?
 

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