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have a '71 140, points adjusted, tried other items like coil, condenser, etc. It produces no fire, with two different spark testers, I can't get a spark. Engine turns over fine, but just won't fire. What am I missing??
 

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Discussion Starter #3

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LOT's of things could be bad, but probably just one! First, and easiest, is remove cover on points, crank and look for sparking at points. If sparking, could be bad primary wire from coil to plug. If no spark, disconnect condenser and crank again. If still no spark, time to get a meter out!

Set meter to ohms, check from - on battery to hex on spark plug, should be "0" ohms. Set meter to DC volts, turn key on and check ground to + side of coil, should be 12+ volts (battery voltage). No voltage, bad ignition switch. Do some more checking and get back. Bob
 

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okay, probably stupid question, if I stick a flathead screwdriver in the points and it fires (through spark plug wire tester), I have spark, but still probably don't have the points adjusted correctly right? No spark by itself, but a little help with another piece of metal and a strong spark occurs.
 

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Check this video...it explains how to set points very well...it sounds like yours are not opening if I understand your explanation
 

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okay, probably stupid question, if I stick a flathead screwdriver in the points and it fires (through spark plug wire tester), I have spark, but still probably don't have the points adjusted correctly right? No spark by itself, but a little help with another piece of metal and a strong spark occurs.
If that is the case the points are not closing. Pull off the distributor cap and bump the engine while watching the points. The rotor will follow the distributor cam and eventually open. Adjust the points at their highest point on the cam for whatever Deere recommends. Bump again and the points should close on the distributor cam flat spot / lowest point. If they do not then you have not adjusted them properly.

2446395
 

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I understood your explanation to mean that you are putting a screwdriver blade between the contacts on the points and forcing them apart...allowing the spark ...Oldgibsonguy's response makes me thing that he believes that you are sticking the screwdriver between wide open points and causing it to arc...can you tell which it i?
 

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Doesn't matter. If he only get's a spark by bridging the points then they're not closing.
 

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To me it sounds like points were not set on high point on cam. Engine makes 2 complete revolutions for high spot on cam to open points.
Remove spark plug and rotate engine by hand while watching points. When you see points start to move/open, turning engine VERY slowly. As soon as points START to close, set gap at .018"-.020". Bob
 
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