I have a GSM Wood Chipper fitted with a Briggs & Stratton 18HP OHV V Twin engine. It was running fine & chipping wood fine. It suddenly stopped & will not fire or start. There is no sign of it trying to catch. I have pulled both spark plugs & they are wet with fuel, so it looks as though its not a fuel issue. I grounded both spark plugs against the crankcase & neither produced a spark, so it appears the problem is electrical. I cannot see any obvious signs of wires coming loose. Is there a way of bypassing any potential shorts/kill wires? Many thanks, Terry
Would need to remove the blower housing and disconnect the ground wire from the ignition coil and crank to determine if it is the coils or a short in the system. But if both coils have failed at the same time I would be worried that something has shorted and sent 12V battery voltage to the ignition.
Thanks & have just done that. Thankfully by disengaging the kill wire both coils produce sparks, so the fault lies in the kill wire connection (somewhat easier to remedy!)
Many thanks for your input. Regards, Terry
Thanks & have just done that. Thankfully by disengaging the kill wire both coils produce sparks, so the fault lies in the kill wire connection (somewhat easier to remedy!)
Many thanks for your input. Regards, Terry
Now something to keep in mind with Briggs. The kill wire contains the crosstalk diodes, and could be the issue. If the diodes go bad the modules will crosstalk and kill spark.
Thats interesting, are they easy to replace? Thanks, Terry
#6
Farmer Jean
Don't forget to take a look at the shear key, it's super easy to break one in chippers and tillers, and it will instantly throw the timing off, stop the engine, and not even try to fire. The timing is off once the shear key breaks...
At least it's an easy cheap fix if that's what happened!
If you disconnected the single kill wire at the kill switch area and it run ok the diodes are ok, it's the kill switch wire area being grounded.
If you had to disconnect each wire at the coils to get a run then one or both isolation diodes are probably bad.
They are not EASY to replace but you can buy the kill wire briggs harness that has both diodes.
I've used 1N4007 diodes and heat shrink tubing as replacements with good results. (1 amp at 1000 PIV diodes and get 10 for about $4)
They have to be soldered in with same polarity as the bad ones.
One thing that wipes them out fast and the magnetos fast is if a voltage gets applied to the kill wire.
Thanks for that. Yes, it was the single wire I disconnected, not the individual kill wires to each coil. From what you say I need to see where the kill wire is shorting to ground? Thanks again, Terry
