Small Engines (Lawn Mowers, etc.): 18 H.P., crankshaft, pulley

Question
Have a 18 h.p. motor that turns a little then stops. Tryed with a wrench still it turns than stops. This is a twin B&S motor. I took plugs out can see one valve move. Could i have one stuck? If so can free it up without taking head off or not? Thanx Pat

Answer
A stuck valve can cause the problem.

Have you removed the top engine sheet metal cover?  If not, remove the cover and see if there is something causing the engine not to turn.

Do the same on the crankshaft output/pulley side.  Make sure something else external to the engine block is not binding.

Finally, there is an inspection plate on most of those Twin cyliner L head engines.  You can remove the plate and see the rods, cam and valves.

Let me know what you find.
Eric