I've got a 2000 Exmark Turf Tracer HP that is in good shape other than the motor. Somehow, where the coil attaches to the block the cylinder cracked. My questions are: Is the cylinders removable or is the entire block one peice? If the cylinders are removable, can I replace the cracked one? The motor on there now is a Kawi FH451V-AS04. I can't find that exact FH451V will any FH451V-XXXX do? They now come with FH541V (17hp) will one of those work? Also, what experience have you guys had swapping out motors?