I have lost spark on lawn tractor with a B&S 19HP twin cylinder engine. I suspect that it may be the coil. I also thought it may be one of the safety switches but if it were one of those the engine wouldn't even turn over would it? The B&S website tells me how to check coil with ohmmeter. If I understand it correctly, I connect one meter lead to a spark plug wire and touch the other to the lamination stack or frame of the coil. The reading should be between 2500 and 5000 ohms. Does this need to be done with the coil still mounted on the engine or can I test it just sitting on a table? I have tried both but I get no reading either way I try it. Is my coil bad or is this not an accurate way of testing the coil?? Thanks

Is neither side of the engine firing, and do you have a single coil with two leads coming from it , or do you have the two separate coils?

I have a single coil with two leads and I don't have spark on either cylinder.

Have you disconnected the small black wire from the coil and checked for spark? The small black wire is the kill wire and sometimes gets a naked spot on it, shorts out and prevents starting, or running of the engine.

I have checked for spark with the small black wire disconnected and still get no fire.

If you are not getting fire with the kill wire disconnected, then I would suggest it being the coil(armature magneto) being bad. When installing the new coil, have a business card handy, this will be used to adjust the gap between the coil and the magnets on the flywheel.