here is something i tried .... with the head on take the engine off the truck turn the flywheel till you get resistance, holding it by the flywheel tilt the engine to the side with compression and see if the compression will hold it up or will it fall over if it holds up then more than likely its not shot if it falls then it may be gone but on a 1/4 to 1/2 gallon it should be fine unless it was ran extremely lean ....300+ degrees,................mine did the same thing but after about 7.5-8 gallons of fuel