Another 8N that wont start

I've got a 51 8N converted to 12v that i start up and run every week (for 17 years now). Today it just would not fire up. It cranks just like normal. I've determined that there is no spark to the plugs. I checked the coil and got 4 ohms. I checked the connections/wires and all looked good. I checked the points and the gap is correct. The rotor in the distributor looks good. The only thing i haven't checked is the condenser, and i am not sure how to test it. Any advice would be appreciated. Thank you
 
Did you try cleaning the points? Just draw a piece of paper bag through them while they are closed. Are you getting battery to the coil?
 
(quoted from post at 00:44:46 03/28/21) Did you try cleaning the points? Just draw a piece of paper bag through them while they are closed. Are you getting battery to the coil?

I will clean the points first thing in the morning!
 
Confirm that you have voltage to the coil. Battery voltage, points open. About half that if the points are closed.




Do you have battery voltage across the points when they are open? (with the points open, put one probe on one side of the points & the other probe on the
opposite side of the points) Verify the gap on the points at .025. Then, 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. (I always spray my feeler gauge blade off w/ contact cleaner.) Make sure you have voltage across the points, as in past the insulator on the side of
the distributor. That is a very common failure point on sidemounts, along w/ the attached copper strip. It's hard to find a short there because it is usually
an intermittent . So 'wiggle' the insulator & the copper strip a bit when you are doing your checking. If you find the short there, the Master Parts catalog
lists everything you need on page 154. You can make the strip and you could also make the insulators as well. But, somethings are just easier & in the long run
cheaper to buy. Get the strip, 12209, screw 350032-S, 12233 bushing & 12234 insulator & just replace it all.





If you just replaced the rotor & lost spark, put the old one back in. Insure that the rotor fits firmly on the shaft & that the little clip is there. Make sure
the distributor cap is not cracked, doesnt have gouges in it from the rotor or brass shavings & doesn't have carbon tracks. Check continuity on the secondary
coil wire. Make sure it is firmly seated in both the cap & the coil. Next, remove the secondary coil wire from the center of the distributor cap, turn the key
on & crank the engine while holding the end of the wire 1/4 from a rust & paint free spot on the engine. You should see & hear a nice blue/white spark. If not,
you have a bad coil or condenser.
75 Tips
 
Though anything is possible, I don't think you have a bad condensor. Ten years is a long time to go on a set of points. Always begin with a true root cause problem solving method before buying new parts and replacing without first verifying old one is defective. Sometimes it is the basic, overlooked stuff that gets you. Did you check the battery? If tractor hasn't been started in a while, say ten days or more, and you don't use a float charger to keep it fully charged, then chances are the battery is weak or even dead. A basic trickle charger won't help. Take battery to a trusty, local shop and get tested on their bench. You can't do much electrical testing without a good, fully charged battery to start with. Get a good brand, cheap, bargain house units tend to be junk, some even out the door, and usually have poor lifespans - 2 years or less typical. Next is to verify the wiring is correct. get your Essential Manuals, and a copy of WIRING PICTOGRAMS by JMOR to use as a reference guide. 99.98% of all non-starting issues are due to mucked up wiring regardless if OEM 6V/POS GRN or a 12V/NEG GRN switch over job. BTW, year doesn't mean much, only if front mount or side mount matters.


FORD 8N ANGLE MOUNT DISTRIBUTOR:
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8N 12V SWITCHOVER ON THE ANGLE (SIDE) MOUNT DISTRIBUTOR:
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*PICTOGRAM courtesy of JMOR

OEM 8N WIRING(6V/POS GRN) AFTER S/N 8N-263844 WITH ANGLE (SIDE) MOUNT DISTRIBUTOR:
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FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS:
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Tim Daley(MI)
 
(quoted from post at 12:48:50 03/28/21) Confirm that you have voltage to the coil. Battery voltage, points open. About half that if the points are closed.

Next, remove the secondary coil wire from the center of the distributor cap, turn the key
on & crank the engine while holding the end of the wire 1/4 from a rust & paint free spot on the engine. You should see & hear a nice blue/white spark. If not,
you have a bad coil or condenser.
75 Tips

With the points open, i have 12.1 volts. With the points closed, i have zero volts.

I removed the center wire from the distributor cap and hald it near bare metal while cranking the engine and got a nice blue spark.

Distributor cap looks to have no cracks or other obvious issues.

Not sure what to do next
 
(quoted from post at 11:56:00 03/28/21)
(quoted from post at 12:48:50 03/28/21) Confirm that you have voltage to the coil. Battery voltage, points open. About half that if the points are closed.

Next, remove the secondary coil wire from the center of the distributor cap, turn the key
on & crank the engine while holding the end of the wire 1/4 from a rust & paint free spot on the engine. You should see & hear a nice blue/white spark. If not,
you have a bad coil or condenser.
75 Tips

With the points open, i have 12.1 volts. With the points closed, i have zero volts.

I removed the center wire from the distributor cap and hald it near bare metal while cranking the engine and got a nice blue spark.

Distributor cap looks to have no cracks or other obvious issues.

Not sure what to do next

Next step is to check spark at the plugs.

TOH
 
i have 12.1 volts.

Your battery is nearly dead. A fully charged battery will read 12.65 volts. Charge the battery.

What was the point gap?

Did you dress the points w/ card stock or brown paper?
75 Tips
 
(quoted from post at 17:14:30 03/28/21) i have 12.1 volts.

Your battery is nearly dead. A fully charged battery will read 12.65 volts. Charge the battery.

What was the point gap?

Did you dress the points w/ card stock or brown paper?
75 Tips

UPDATE:
The good...i have a good spark at each plug and the plug tips are clean and dry.
The bad...the engine just cranks but won't fire up.

I've verified the fuel flow is adequate, but when i took the air inlet tube (?) off, a bunch of gas spilled out so maybe i flooded it.

Currently charging the battery up (no pun intended).


I've checked the f
 

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