Butt kickedby19.5hp Briggs's and Stratton

Mower would not start so started diagnostics. Removed and cleaned carb. Getting fuel. Spark plugs are new but are not firing. Checked coil/magneto. Would not pass ohms test. Ordered new coil on Enay and received it, it would not pass ohms test nor fire the plugs. Contacted seller and they promptly shipped me another coil without any associated seller flak. Received the second coil and it will not pass the ohms test nor fire the spark plugs. Contacted the seller again and they are sending me a return label. The seller AMC has been great to work with but I still have a non running lawn mower. The coil should ohm out by positive lead to plug wire end and negative lead to laminated metal on coil set at 20k with a reading somewhere around 8000 but I get nothing using two different meters, one of which is brand new. The coil will fire if you ground the lead to a head bolt. I cleaned all grounds and even grounded the engine to the frame. Still nothing. I am at a loss, any ideas ?

Does this bugger still have points hidden under a cover behind the flywheel? B&S had a little phenolic pin that pushed the points open that got stuck occasionally.

Not that I'm aware of, this a magnatron style coil with the Horse shoe laminate and the metal pin that projects out of the windings and is passed by the magnet on the flywheel, some call it a three point coil.

Just two wires? One to the plug and one to stop switch? If so. Put two layers of masking tape over the magnets on the flywheel. Turn it to match the magnets to the coil. Loosen the coil so the magnets pull it up tight. Tighten the coil bolts and turn the flywheel to remove the tape. Turn it again to be certain the flywheel doesn't rub. Put a plug in the plug wire and ground the plug. See if you get spark.

Oh be sure the start wire is not grounded.

Thanks V but I've already done all that. :builder: :head bang: :swoon:

Did you check the plug wire isn't broken or loose from the plug connector?

I'm still used to the old motors. Maybe this link will help you.
https://www.briggsandstratton.com/na/en ... sting.html

Yes, nothing broken on the old coil or the two new replacement coils and the kill wire disconnected. Motor isolated from rest of mower so it should just sit there and run. I'm baffled. I don't understand why it will run on one cylinder for a few minutes and produce great spark if I ground out the other plug wire to a head bolt. It does that on both new coils. I will check the link out. Thanks V !!

My mower is a Honda. It just runs.

If it's a wasted spark system, and one plug or wire is bad, neither will fire. Try it with different plugs and wires. (if the wires are removable)

If you ground #1 plug wire and #2 fires, does #1 fire with #2 wire grounded?

You did think to try new plugs right? Probably last on my list most of the time.

Good News!!! It's alive !!! Coil was not grounding through the mounting bolts into the cylinder that it mounts on top of. I had previously cleaned all grounds including bolts but it didn't decide to cooperate until I tried it one more time. Runs like a charm now. The seller sent me a return label to issue me a refund so I will let them know that it's not needed and he can relax. I've already mowed two acres of yard without any problems. Thanks for all the help, I was contemplating buying a new mower and then dudes are expensive !!!

Perseverance wins the day! :good:

My neighbors are real busy now that I've cut my grass. Thunderstorm warnings here for tonight. All is well it seems! :BigGrin:

Excellent!