DT 55HP running at half speed

[Derek1980]

Good day all,

I have a 1985 DT 55HP (oil injection) engine, I have only had it for a short period of time and have only used it once. I am only getting approximently 12.5 mph (20.1 km/h) out of it at full throttle. It's pushing a 14 ft fiberglass speed boat. The oil injection system was disconnected when I bought it and I have been using pre mixed gas. Could the fact that the oil injection is disconnected be the cause of the engiine going into "limp" mode. If so what can I do to rectify it other than reconnecting the oil injection?

Your responses are greatly appreciated.

Derek

[mphelle8vld]

Need more information. Was it operating properly when you bought it and then you removed the oil injection? Did you (or the previous owner) remove it and if so, what was done with the wires to the oil tank? What rpm is the motor at full throttle?