8n not sparking

[Ron Graves]

More 8n woes for me...Got the tractor to turn over, but it will not spark. I am sure there are some great troubleshooting tips, wondering where those might be...It is a side mount dist, with a 12v conversion.

Anyone that can help, I would be appreciative...

 

[Bruce(VA)]

Do you have battery voltage across the points when they are open? 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 guage 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 carbon tracks. Check continuity on the secondary coil wire. Make sure it is firmly seated in both the cap & the coil. In fact, replace it temporarily w/ a plug wire. 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.



Post back w/ results; I'll be interested in what the problem was.
50 Tips

 

[souNdguy]

if the bat is charged, and it turns over good, check that you have power tot he coil.. if you do, then check points.. they are gapped at .025 and must open and close.

post back.

you can use a test lamp and run the starter over.. test lamp should blink when probing connection at dizzy.

if it stays on, points don't close.. if it stays off, points are closed up, or otherwise shorted. ie.. feedthru insulator possibly.. etc.

post back

soundguy

 

[Ron Graves]

So I fashioned a test light out of an only tail light, an alligator clip (can t find the second one) and a wire. When the wires were hooked up to the minus side of the coil and the ground, I got a steady light. When I hooked up the wire from the distributor to the coil on that same post, the light went out. i have not turned it over yet...

As Col Clink would say, "That is velly velly intervesting......"

What do you think it is?

 

[souNdguy]

test must be done static at first to see if you have power to the coil, then you MUST turn it over to see if the points open and close, ad whether it breaks the ckt or not.

 

[Ron Graves]

As I had said, the test light works on both sides of the coil, except when the wire to the dist is attached. I am ordering the parts Bruce suggested, thinking that there is a problem there. The points are opening and closing (took the cap off the dist and turned it over), but still no spark....ugh!

 

[Dell (WA)]

Ron........didja know closed points are GROUND??? and surprizingly enuff when ground is applied to the 3rd terminal of yer roundcan coil, guess what??? GROUND is ZERO VOLTS. Isn't that amazing??? So even when you see the points opening and closing, guess what, you could still be GROUNDED inside that nylon feedthru at metal side of yer 5-nipple dizzy. And guess what??? You only gitt sparkies when the points OPEN. (ie...un-ground)

Ittz goode that you have volts at all 3-terminals of yer roundcan sparkie coil. That means the coil is good.

BTW, didja know GROUND can be positive (+) and negative (-) at the same time??? .......spooky, Dell, yer self-appointed sparkie-meister

 

[souNdguy]

re-read mine and dell's posts.

you need to follow the troubleshooting thru. just because points mechanically open.. they may still be shorted.

sniff it out with a test lamp or vom

 

[Ron Graves]

Actually, I really did not understand any of what you wrote here...

Sorry, I am new to this, never really have done a lot of repair work (Not afraid to get dirty, turn a wrench and follow instructions)and what you have said makes absolutely no sense.

 

[Royse]

Ron, in my humble opinion I think Bruce. Dell and soundGuy have you on the right track here. (sorry if I missed anyone on the same note) The points/wire to them are grounded some how. Maybe the insulator.
I can help with meter reading and tracking grounds if you have a multi-meter. Any cheap one would work for ohm readings, analog is better if you want to measure just about anything else on your N.
Bruce mentioned checking battery voltage across your points when they are open, that you could basically do with your test light. Even if its a little low it should light the light. If it does not, that would point even more to the grounded condition.

 

[Ron Graves]

Ron, in my humble opinion I think Bruce. Dell and soundGuy have you on the right track here. (sorry if I missed anyone on the same note) The points/wire to them are grounded some how. Maybe the insulator.
I can help with meter reading and tracking grounds if you have a multi-meter. Any cheap one would work for ohm readings, analog is better if you want to measure just about anything else on your N.
Bruce mentioned checking battery voltage across your points when they are open, that you could basically do with your test light. Even if its a little low it should light the light. If it does not, that would point even more to the grounded condition.[/quote]

I have ordered the parts that Bruce suggested. I have a friend who is a mechanic, who, after replacing the new parts and it still does not work, is going to come by and see what is up. His only comment was..."WOW, I have not worked on something with points in a LONG time..."

I am a very visual person. I need a picture to make sure I am doing this right...sorry to be a pain...

 

[Royse]

No pain in my opinion, I understand learning better visually.

Just trying to help!

 

[Ron Graves]

Had a friend stop by. Did not know he went to school tO fix jet engines. Showed me a shortcut that showed that you were right. I hopefully will have it running by Tuesday before i go to bed if the parts come in.

 

[Bruce(VA)]

That's nice to hear!

Tnx for the follow-up.
50 Tips