I have a JD 170 w/ the FC420 motor I salvaged off of E-bay......My 12 year old son used it to mow 3-5 yards in the neighborhood last summer ?ran great, but blew-it up plowing the driveway this winter...Have not had a chance to tear it down, but appears to a terminal . I was wondering, with new replacement parts (crank, piston, etc) few and far between for the K-FC420...IS there another new engine that can dropped in and hooked-up?