Wisconsin S-7D Motor refusing to start

On an S7D there is no distributor,just a magneto that the spark comes from,if you lay the plug on the head with the sparkplug wire connected to it,you should be able to see a spark jump the plug gap.If you don't have spark,which does sound likely,the first thing to do is clean and reset the points,they are in a little box under the carb near the bottom of the engine.If you take the cover off,you'll see the points,make sure they aren't oil soaked,that the points are shiny and the contact surface is flat,you can file them flat and shiny with an emory board.After your sure they are clean put them back in and set the gap to.020,then check your spark again.

If your sure you've got spark and it won't start by spraying starting fluid in the carb or putting a little gas right into the cylinder,then you need to see how good your compression is.The most common problem that I've found on those old Wisconsin engines is the exhaust valve being stuck open,if the engine has been sitting for awhile,it's a possibility.After that,there is a chance that the rings are stuck in the ring grooves and won't let the piston build enough compression.Has the engine been sitting for awhile?