The little node testers will practically light if you give them a stern glare. If you remove the kill wire from the coil and give it a spin it will have spark at the plug if the coil is good.

Yeah.. Thanks for that.. Did it and still no spark, so I guess I am comfortable with buying the coil. Thought those things were virtually hassle free. "To every thing, turn turn..."

Coil failures are somewhat rare in B&S and Tecumseh engines, but obviously it can and will happen. Another thing with the Tecumseh is the magnets are on the inside of the flywheel and have been known to come off. At least, I've heard that a few times on the forum. I'm not sure if the late Tecumsehs were still like that. You'll find out when you remove the air shroud to get to the flywheel/coil - probably you should remove the air shroud and take a look before buying the coil, and clean the cooling fins while you're at it. You could simply have a loose coil.

Thanks for that. Definitely had it apart. Magnet is strong (Built into flywheel) Grabs/Holds a 3/8 ratchet easily. It was rusty, so I sanded it clean. Hope I did not screw it up when I did that. (Sanded the flywheel and the coil fairly lighthandedly)... Got one coming from Amazon... Only $21.. after market... Hope it works out.. thanks again...D

Let us know what happens. You didn't harm the flywheel by light sanding of the magnets but keep in mind it is a balanced assembly.

"Can the coil just be too weak to make the plug spark, but still light the tester?"

yes, you need megavolts for the spark plug to spark. if you connect the tester straight to ground, you dont need to jump through air to close the circuit.
If you had the old Tecumseh like mine that has points ignition, replacing the condenser\capacitor would fix the problem.

Thanks.. Yea.. Not very old.. Just the coil (magneto).. Got one on the way.. Here on WED.. let ya'll know what happens..