# 6.5 hp Briggs & Stratton lawnmower -no spark



## ddsaugus

I have a no spark problem on a 6.5 hp lawnmower. I have replaced the coil (twice), replaced the flywheel, have a new spark plug. I've removed the ground wire and still no spark. 

Does anyone have any additional suggestions? I've run out of things to try.


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## jrrdw

What make and model lawnmower is it? We need the model numbers, serial numbers. The engine numbers as well.


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## ddsaugus

The lawnmower is a Troy Bilt Tru Cut 100 Triaction 21" pushmower. The engine and serial numbers are: 125K02-0243-E1-04042858.

Thank you!


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## jrrdw

Is this your mower? 

21" Walk-Behind Push Mower by Troy-Bilt

Follow the cable from the engine brake (the handle you have to hold to keep it running) down to the engine. Where the cable locks into the bracket under the cover there is another kill switch. Have you checked that switch? Take the wire off there and try it again. Work the handle and make sure the switch is being deactivated when you pull the handle.


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## ddsaugus

Yes, that is the correct lawnmower.

I rechecked the switch at the end of the cable and again removed the ground wire - still no spark.


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## jrrdw

This is your engine break down. Does your engine have the "interlock" #935 in the break down. According to your given code date you should have it. If it does try unplugging it and see if you get spark.

Some of the wire harnesses have diodes and some don't, witch does yours have?


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## ddsaugus

I have brake assembly #923A. There is no interlock switch that I can see. This looks like a simple system: there is no wiring, except for a short grd. wire running from the brake to the coil. I have disconnected this wire. I hope that helps!


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## jrrdw

Wow, make very certain that non of the grounding wires are touching anything but the holders they hook up to and have good covering (so it doesn't ground the coil where you can't see it). Make certain when you squeeze the handle for the engine brake that it's completely disengaging the switch. 

Other then that I would have to have it in my hands...


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## ddsaugus

After many hours of scratching my head, I retaced my tracks and they kept leading me back to the coil. Come to find out I had 2 new B&S coils out of the box that were bad. I had a hard time convincing the parts department that both coils were bad. It appears that they have no way of checking their working status.

Thanks to a friend that had the same mower, I was able to test the new coils to prove they were bad out of the box.

Thanks to everyone for all the help.


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## griffle

Is the following a valid way to test a Briggs and Stratton lawn mower coil (model # 125k02)? I put one probe of my ohm meter in the cap of the spark plug wire, and attached the other probe to a spot on the engine. The ohm meter registered continuity between the 2 locations. This would seem to mean that the coil is bad, since a "hot" electrical wire should never have any contact with a "ground" point. Am I right? If not, where is my reasoning faulty. Thanks for any help you can offer.


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## Mr.Hambone

We sent the wrong number to the company when they asked for our Engine ID. Now we found a number like ddsaugus found. It is 125K02-0500-E1 05011758. would this be the engine ID?


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## jrrdw

griffle said:


> Is the following a valid way to test a Briggs and Stratton lawn mower coil (model # 125k02)? I put one probe of my ohm meter in the cap of the spark plug wire, and attached the other probe to a spot on the engine. The ohm meter registered continuity between the 2 locations. This would seem to mean that the coil is bad, since a "hot" electrical wire should never have any contact with a "ground" point. Am I right? If not, where is my reasoning faulty. Thanks for any help you can offer.


If you get continuity from the spark plug wire to the engine and all the kill switches are disengaged then yes, the coil is shorted. If any of the kill switchs are engaged they are doing their job and shutting the engine down.



Mr.Hambone said:


> We sent the wrong number to the company when they asked for our Engine ID. Now we found a number like ddsaugus found. It is 125K02-0500-E1 05011758. would this be the engine ID?


Yes that looks like a typical engine ID number. Look your engine up here. If you want to see the break down diagram.


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