I have a 2000 BX1800. I put an aftermarket fuel shut off solenoid on it. When the key is turned off, the solenoid moves slowly and takes a few seconds to shut down. Would this cause the tractor to be hard to start next time ( allowing fuel to enter cylinders)? I have black smoke and shakes a bit before coming to life even in warm weather. I have cleaned fuel injectors, checked glow plugs. I plan to check voltage going to the solenoid and try a jumper wire straight from the battery to the solenoid to see if it moves faster.