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Discussion Starter #1 (Edited)
Hello,

I have a 316 John Deere onan tractor and it is around 1986 the year I believe. It was working great for months. I parked the tractor and it was fine. Next day I came out and it really did not want to start. I changed the plugs, filled the tank and everything seems to be ok. I used starting fluid and got it started however it does not have any power. The faster I go the more it wants to stall and shut off. Its getting plenty of gas. I am also getting spark. If I remove 1 spark plug the tractor will start fine and seems to be alright. When I put it back in it has a hard time starting and if it does start it still does not have any power with the PTO on and also PTO on makes no difference. It on a flat level lot I am using it. The tractor does burn oil.

Im stumped.

Thanks in advance.
 

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Sounds like a dying coil.

Do you have a multi meter?
 

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Primary resistance+ to - should be around 4.5 ohms. The secondary being + or - to a plug wire terminal is I’m guessing roughly 15k ohm on an oem coil, 25k on an aftermarket.

It the coil tests in spec I would replace both plugs and wires as a hunch. The coil is in series, so strange things can happen from faulty parts.
 

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Discussion Starter #5
Primary resistance+ to - should be around 4.5 ohms. The secondary being + or - to a plug wire terminal is I’m guessing roughly 15k ohm on an oem coil, 25k on an aftermarket.

It the coil tests in spec I would replace both plugs and wires as a hunch. The coil is in series, so strange things can happen from faulty parts.
do i check it when the tractor is off and the key off or turn the key on but dont start it? sorry for the newbie question.

Thanks
 

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do i check it when the tractor is off and the key off or turn the key on but dont start it? sorry for the newbie question.

Thanks

Disconnect all wires
 

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Discussion Starter #7
Disconnect all wires
Hello again,

No Luck with replacing the coil, ignition wires and spark plugs. One of the cylinders is not firing at all. There is plenty of spark and its getting plenty of gas. The cylinder is cold but the other side is working fine.

Thanks
 

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Do you know how to do a compression test on a cylinder? Since you say it is getting spark, fuel and air, the only thing missing is compression. So we need to find out what compression the non working cylinder has. If compression checks out (do both cylinders), then a leak down test will be needed.
 

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Do you know how to do a compression test on a cylinder? Since you say it is getting spark, fuel and air, the only thing missing is compression. So we need to find out what compression the non working cylinder has. If compression checks out (do both cylinders), then a leak down test will be needed.
no dont have a compression tester. I will have to get one.

Thanks
 
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