I have a 1993 LX178 that I bought new. It has the Kawasaki FD440V twin cylinder liquid Icooled engine. This spring it started "acting up" After 25 to 30 minutes of mowing it will start cutting out, drop a cylinder and stall. After it cools down, it will start up and mow for another 25 or 30 minutes. I don't think it is a fuel or carburation problem as I have checked all of that system. It has fresh gas, and a new fuel filter. Fuel pump works fine and carb has been rebuilt and does not leak. It has new, properly gapped plugs and a new battery this spring. I suspect one of the coils is bad, or the ignition box itself is bad. As they heat up, it causes the open circuit, and the dropped cylinder and stall out. As both of these parts are expensive, I hate to just buy and hope they solve the problem, since I know you cannot return used electrical parts. Is there any way to test these? I have a VOM meter and know how to use it. Any other ideas? Thanks in advance for any help.