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The spark plugs may have got flooded and are now shorting to ground up inside the shell instead of firing at the electrodes....sometimes just letting it sit a few hours will let it start again after the excess fuel evaporates..other times the spark plugs refuse to fire right ever again and replacing them gets the engine to start..even if you hold the choke open and floor the throttle to dry and un-flood it..

I've had Champion plugs die like that in older chevy small blocks before,once they gas fouled nothing would get them to come back to life..put in new plugs and it would fire right up--this happened a lot when they went to wide gap plugs & HEI ,and in cold weather the choke pull off failed to open the choke enough right after starting...once it stalled ,you could crank it till the battery died unless new plugs were installed..

The way your engine cranks normally then binds up may mean one plug wire might not be on the right plug,re-check the firing order..it could be too far advanced too..
 

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timing might be off just a little. Take the distributor off and retime it, check point gap and make sure they are clean. Switch to a NGK plug and double check that plug wires are running to right plug.
 

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Discussion Starter #4
You’re both right. I revisited the timing again and that binding thud went away. Now I’m getting it to fire on some cylinders but it doesn’t really start running. Timing it is such a pain for me. I think the fact that my dist cap is held on so loosely adds to the trouble. The starter spins while I hold the button down, but it doesn’t fire until I let go of the button. I’ve tried rotating the distributor left or right to try to find a spot where it actually starts better but can’t.
 

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Discussion Starter #5
Here’s another symptom I just noticed. I took a spark plug out and leaned it against the engine block while pressing the starter button. I get no spark while holding the starter button, but it sparks as soon as I let go of the button.
 

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Here’s another symptom I just noticed. I took a spark plug out and leaned it against the engine block while pressing the starter button. I get no spark while holding the starter button, but it sparks as soon as I let go of the button.
Weak battery. Put it on a charger for a day or two and get it charged up good. Then try it.
 

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That might be a possible cause,but his battery sounded pretty strong in the video--unless its been sapped down from the repeated start attempts..wont hurt to charge it up again,maybe you'll get lucky..

It should have spark both during cranking and with the ignition "on"though...


I'm not real familiar with these old Fords,but my 600 Ford had a solenoid / relay switch for the starter instead of a push button,the button was still there,but not connected---maybe it was "upgraded"by a previous owner--anyways,the starter relay had two smaller terminals,one got 12V from the ignition switch in the "crank" position to make the starter crank,and the other terminal ,labeled "I" fir ignition,sent 12V while cranking only,direct to the coil,by-passing the ballast resistor,to give it hotter spark while cranking..then once it was started,the coil got power from the ignition switch and it had to pass thru the ballast resistor ,then to the coil...

I'd try hot wiring the coil right to the battery--the wire the points are NOT connected to,then crank it and see if it starts--then you'll know for sure for some reason the coil isn't getting power when its cranking over..
 

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Discussion Starter #8
It's definitely not the battery. It's a brand new battery that I installed yesterday, and I had a big battery charger on it in jumpstart mode while cranking. From the digging I've done, it is probably one or more of the following things:

1. I just converted this thing to a 12v system and installed an alternator. The kit just came with a resistor and I still have the original 6v coil. I never had any other resistors in the system before. Perhaps I need either a 12v coil or another ballast resistor? I'm confused because I've read in some places that you need the original ballast resistor that is on the terminal block along with the new ceramic resistor?

2. I tried checking the voltage coming out of the ceramic resistor that came with this alternator kit. Holding one lead of the multimeter on my battery negative, and the other on the output side of the resistor, I was reading 4.7 volts. My understanding is it needs to be like 6-7. But then after I let it cool down, I was reading 13.3 volts. So I really don't know what's going on...

3. Then I realized this after I left already that the tractor used to be a positive ground 6v system. I just switched it to negative ground 12v. I never switched the leads going to the coil. Does the coil need to receive positive to a specific terminal on it, or does it not matter?

4. Lastly, I do need to check my wiring again because the solenoid thing does sound like my problem. The tractor sputters as soon as I let go of the start button but doesn't even try while I'm holding it down.
 

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When I switched my 8N to 12 volt, I added a new 12 volt coil and resistor. The wiring is as follows. Positive from switch to resistor to positive side of the coil. Listening to your video, you are not getting any spark. It may be to simple but a bad key switch could cause a problem like this. It was said before, but with the key on you should have fire to the points.

It is a problem with the "electric" going to the engine. Only a few parts. If it does fire "sometime" I would try the switch fix to see if you get fire to the plugs. If timing is close and the points are gaped and not burnt, MAYBE a condenser? Only parts are the switch, resistor, coil, points, condenser and plugs. Also the wires between. One of these IS your problem.

*With kids around loosing keys, my dad never had keys for the 8N and he just twisted the two wires together to "turn the key". He never had a switch problem.*
 

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A 6v coil running on 12v with no resistor isn't going to last very long. Did you change the ignition switch or are you using the original one?
 

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Discussion Starter #11
I never had a key switch for this tractor. I just have an on/off rocker switch. I test it by checking for continuity between the terminals when the switch is on, and there is continuity. I suspect it's because i never reversed the terminals on the coil since I switched this to a negative ground.
 
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