It seems like a person could do a pretty good check by flying for at leat 4-5 min....make a way out full throttle run, cut the ignition & glide the airplane in. Take the sparkplug out and if it is a tan or light brown color...you should be good to go. It is good pratice for a dead stick landing. I have over the years done many dead stick landings on purpose. You got to know how your plane is going to handle it first. Capt,n