Opposed twin just died

PTmowerMech

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Craftsman 917.270820
Briggs 422707 1516 01

Finally got all the repairs done on this, none related to this, except for maybe the new aftermarket carb. (4 bolt filt pump)

Ran like a champ. Mowed good. Very little power reduction when I engaged the blades. Was pulling it up on the trailer when it died.

So far I've hollering at it, threatening it and even kicked a tire or two.

When that didn't work, I checked the fly wheel key.... Good.
Replaced the coils with some other used ones. One was working when I took it off another opposed twin. Neither of them fix the problem. (I don't trust my spark tester. Even though it didn't show there was any spark on either of the used coils I tried.
Disconnected the kill wire on the coils (all of them) and that didn't work. Which should eliminate the possibility of it being a safety switch, right?
It's got gas. I can see it down in the carb coming through. Before all this, I drained and flushed the tank. There's also little droplets of fuel coming out the top of the carb when I turn the engine over.
I tried carb cleaner to start it, to now avail.

One thing I suppose I should note, the kill wire was bare and touching where it and the plug wires fit through the metal housing in front of the flywheel. But I pulled it out enough to not touch anything.

I'm down to thinking that all three of the coils were bad.
 

Fish

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If you have a bare kill wire that comes in contact with 12 volts, then yes, you may have killed all of your coils. voltage kills them dead, and will kill a brand new one.
 

PTmowerMech

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If you have a bare kill wire that comes in contact with 12 volts, then yes, you may have killed all of your coils. voltage kills them dead, and will kill a brand new one.

I can't remember which coil, 1st or last, I had on it when I realized the wire was caught on that sharp tin. Probably the last one. Thanks for the info. Gonna check out some prices for a new coil.
I can't think of anything else it could be. Honestly. With the kill wire disconnected, that leaves not other reason, except compression. Unless I'm missing something.




I'm really shocked the hollering at it and the tire kicking didn't fix it though. :cool:
 

Tinkerer200

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Well you may need to actually disconnect the kill wire from the coil and check. Don't really see how a bare kill wire would be likely to come in contact with 12 volts at that point so I would make sure you have no fire from the coil before just running off replacing things. Remove plugs, stick a Philips screw driver in a spark plug boot, grasp the shank of the screw driver and place a finger on the bare cylinder and hit the starter. IF you hold on, coil is bad.

Walt Conner
 

tom3

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Might be better to have your brother in law hold that screwdriver. Or hold a spark plug against the side of the block a hit the starter and watch for the blue spark.
 

PTmowerMech

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So the new coil came in and it fired up without the kill wire connected. (I didn't hook it up on purpose) It was a little hard to crank, but she fired up for a few minutes. I killed it and let is set for a few minutes and tried to crank it again. And it would just turn over and over. With the spark tester on there, I can barely see a spark every once in while. So I held the end of the plug to the engine, and got pretty much the same result.
Still no good fire going to the plug.

It was an after market coil off of ebay. But from someone with no bad reviews on their coils.

I'm not sure how to test the magnets, except to put a bolt on it. I did that, and the bolt stayed on the magnets.

I'm at my wits end with this.
 

bertsmobile1

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You check coils with the kill wire disconnected.
The kill wire is a ground circuit so if the wire touches the body anywhere you get no sparks.
On older engines there are usually quite a few sports where the insulation has chaffed through over the years of loyal service.
Try getting some "spagetti tubing" from whatever you have that replaced Radio Shack and push it back over the kill wire.

You might have bad safety switch as well .
I generally bypass the switches one at a time to check his using short jumpers with a spade on each end,
Check the operation of the switches before you start,
The switches are simple sliding contacts between pairs of terminals, flat to flat.
Double. check that you have bot accidentally hooked a kill wire to a cranking wire by testing the kill wire at the coil end for voltage
 

PTmowerMech

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You check coils with the kill wire disconnected.
The kill wire is a ground circuit so if the wire touches the body anywhere you get no sparks.
On older engines there are usually quite a few sports where the insulation has chaffed through over the years of loyal service.
Try getting some "spagetti tubing" from whatever you have that replaced Radio Shack and push it back over the kill wire.

You might have bad safety switch as well .
I generally bypass the switches one at a time to check his using short jumpers with a spade on each end,
Check the operation of the switches before you start,
The switches are simple sliding contacts between pairs of terminals, flat to flat.
Double. check that you have bot accidentally hooked a kill wire to a cranking wire by testing the kill wire at the coil end for voltage

Scratch all that. Apparently the aftermarket coils have writing on BOTH sides of the coil. And it helps to READ what's on it. As in "This side out" vs some digits that don't say "This side out."

Funny thing though, with it flipped over, how did it even start the first time with the new coil? Strange.
 
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