Another fuel spark but no start

Tractor ran great abruptly stopped. New points and condenser got it running again, a little rough.
Quit again new cap and rotor no better. Ditto new plugs, although I plan on picking up 437s later today. It did start with new plugs but very rough. Then back to no start. Swapped known good carb -same no start. Will also try new coil, which I think may be the issue. Can I have "decent" spark, but still need coil?
Acts like no fuel, but great flow, and again swapped proven carb.
52 side mount. 12 volt
Will check timing, but until this happened I've never seen an old gas motor start and run as nice as this one has.
 
What do you call decent spark. The spark can jump the gap at the spark plug when in open air but may not when under compression. Best test is a spark gap that you can set to 1/4 inch or more. If it won't jump 1/4 inch in open air it won't reliably jump a spark plug gap under pressure.

New points is no guarantee of good points. Clean them well, adjust the point gap, recheck the timing.
 
Thanks RM-MN I will do the 1/4" spark test. I will check the timing as well. Can the timing / distributor get off if I have not done any more than points and condenser in distributor? Not questioning your logic, just trying to understand possible cause of this abrupt change.
 
Stop guessing, "...which I think may be the issue..." I suspect root cause is mucked up wiring and not any one component. Is coil 6V or 12V? Test it, don't go by what was stenciled on the box. Fuel flow test pass? Yes? Leave it alone. A 12V battery does not mean it is wired correctly for a 12V system. Is the battery good? Have you had tested under load at a shop? Is your alternator 1-Wire or 3-Wires? The alt replaces the genny. Is the Voltage Regulator removed from circuit? How was it running before you did all that? Points and plugs gapped .025"? Was timing set with a timing light or by the manual method?


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)
 
Tim it is a 12 volt coil.
New wiring done by me as your diagram shows.
We bought this tractor with a known seized engine and put in a recently rebuilt engine from a trusted friend.
Tractor started and ran flawlessly. Have done plenty of light work raking hay etc.
I'll be clear I'm a novice, but question what would suddenly cause such a drastic change.
No timing light, and I never checked timing.
Will do it by manually by my manual.
1 wire alt.
New battery, but it is a reconditioned battery. Will try known new battery from good running tractor.
It does spin over fast. Not tested under load. Points gapped to .025
 



You could have a spark issue.


You could have a fuel issue.


Don’t guess. Troubleshoot. See tip # 13 at the link below.


You need to answer 2 questions before you do anything else:


With the bolt in the carb bowl removed and the gas on, will the fuel flow fill a pint jar in less than 2 minutes?


Next, get out your adjustable gap spark checker * , open the gap to 1/4", hook it up, turn the key on and crank the engine. Does the spark jump 1/4"? Post back
with the answers.


And do not buy a new part for the tractor until you can answer this question: how do I know the part on the tractor is defective?

Once you narrow the problem to spark or fuel, post back and tell us what you found (and how you found it) and you will get plenty of help to get your tractor
running.

And finally, do not mess with the timing. It did not suddenly get out of time significantly to stop running.

* Don't own an adjustable gap spark checker? Buy one! Not a test light! Until then, take an old plug, open the gap 1/4" ground it to the head & look for spark.
It’s not the color of the spark that counts; it’s the distance it jumps.

https://www.autozone.com/test-scan-and-specialty-tools/ignition-tester/oemtools-adjustable-ignition-spark-tester/10257_0_0?
cmpid=PLA:US:EN:AD:NL:1000000:TLS:71700000043798748&gclid=Cj0KCQiAovfvBRCRARIsADEmbRKBdAvAmtFfOvYiYXR7T6NYiW57uyv5-
dEKjVT_h2KogQNUUMsRixYaAlU3EALw_wcB&gclsrc=aw.ds
75 Tips
 
Good indication. Clean the points and check the point gap. Make sure there isn't a short where the wire connects through the distributor housing. Yes, point gap changes the timing. Probably not much but it does change it.
 
Are you using a 12 volt coil or a 6v coil w/ a resistor? (see tip # 30)





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, doesn’t 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. Just put the old condenser back in to eliminate that as a possibility.
75 Tips
 
(quoted from post at 05:00:48 09/11/20) Bruce:
Failed 1/4 test. No spark at all.
Fuel flow good.

little Fred, does "fuel flow good" mean that you performed the test given to you by Bruce? Or that it "seems good"?
 
I did pick up a new coil and condensor while out on errands. NAPA brand. They did not have points.
I wont put them in till I follow above suggestions and tests.
I'll also address the last few comments before heading to tractor.
Fuel flow: yes I said it "seems good" but it passed the 3 minute pint test.
Ignition switch: new, and swapped one from running 9n.
If voltage to both sides of switch is same does that confirm switch works?
 
The point gap may not make a huge difference on these,but on most of the 2-stroke dirt bikes that I used to rebuild,the only way to set the timing was the point gap. Lots of older 4-stroke motors used the point gap for setting the timing as well
 
(quoted from post at 06:44:55 09/11/20) Are you using a 12 volt coil or a 6v coil w/ a resistor? (see tip # 30)





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, doesn t 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. Just put the old condenser back in to eliminate that as a possibility.
75 Tips
Bruce et al
I printed this out and checked off each item. All was good up to and including the secondary coil wire producing a strong spark. The one thing I did not do was install the new plugs I picked up today. They are Champions, NAPA not have Autolites 437, points and I forgot spark plug tester.
Still no start AT ALL.
Please advise.
 
(quoted from post at 16:12:34 09/11/20) Negative, forgot to tell you that.

Tried a second time in dimmer light and yes, there is spark from modified plug.
I do not have any starting fluid or even carb cleaner to shoot into intake. From reading here that may be the next step?
 
I have got it running, but not well.
Have to keep choking it. Knocks.
I drained a quart of gas out into a glass jar to make sure it was not a water issue because thats what it seems like. No water.
Dissasemble and cleaned carb. Needle good,but it also acts like a stuck float.
 
Great news "Little Fred" is running great.
I totally went through the carb cleaning with carb cleaner and wire.
Thanks everyone!
 

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