More often than not catastrophic, sudden and inexplicable over-fuelling is caused by an injector that has failed or got stuck in the open position. I had similar happen on two occasions with car engines, both on Lucas injected Rover V8s. In both cases, pulling the fuel rail off and turning on the ignition immediately revealed the issue as petrol pi55es out at an unbelievable rate from permanently stuck open injector! The first time it happened, just one (out of eight) failed injectors blew nearly four gallons of fuel out the exhaust in a couple of miles! The fuel gets everywhere too, like you noticed: any slightly leaky exhaust joint, spark plug seals, inlet manifold seals etc etc.

Biggest issue with this problem (if it is a stuck injector) is �bore wash� if the motor has been run any distance in a horrendous over-fuelled condition. Carbon deposits get rinsed off the rings and bore and, more crucially the excess fuel washes past the oil control ring and gets into the sump/tank and oil system ruining the oil�s ability to lubricate.

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