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Troy Bilt Trimmer


Gene Spearman's Avatar
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08-05-17, 02:05 PM   #1  
Troy Bilt Trimmer

I have a Troy Bilt trimmer TB425CS that will not shut off. Starts great, but have to pull plug wire to stop it. Replaced kill switch with OEM part and still will not shut off. Have not been able to find a wiring diagram. Any help appreciated. Thanks.

 
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08-05-17, 03:16 PM   #2  
Trace your plug wire back to the coil. It will have a small wire connected to it, or should. That's the kill wire. The switch you put in is a continuity to ground switch. Probably the wire from the coil is either disconnected or broken enroute to the switch.

 
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08-05-17, 06:29 PM   #3  
Thanks. Will give that a try. Was hoping I didn't have to get into the engine that far.

 
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08-06-17, 09:21 AM   #4  
Took trimmer apart down to coil level. Two wires, black and red from switch. No others other than plug wire. Continuity through both wires from switch to coil. Old and new switches test the same, continuity across switch when what should be kill position. Trimmer runs regardless of switch position. What m I missing?

 
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08-06-17, 12:08 PM   #5  
Continuity is from kill wire connector at coil to ground with switch in off position.

The two wires you have - one runs to ground, the other runs to the kill connector on the coil. You have a break in the wire circuit. Either a wire is broken, the wire at the coil isn't connected, or the wire on the other side of the kill switch isn't grounded.

First disconnect the kill wire from the coil, then run the continuity to ground with the switch in off position. Then hook the wire back up to the coil.

 
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08-06-17, 01:22 PM   #6  
I've seen some of these coils fail where the kill wire connector doesn't connect to the inner windings, so even if you ground the terminal with the switch, it doesn't kill the spark. Seen it several times now.


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08-07-17, 12:23 PM   #7  
cheese, I'm going with your thoughts. New wires, connectors and switch. Runs like a top, won't shut off. Shut off will be pull plug wire like I have been doing. Thanks for the help everyone.

 
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