My 1984 Perkins
4108 low oil
went off on idle and after checking the oil
and noticing it was "fine" I replaced the sensor. With the new sensor the alarm
went away so I figured it was a bad sensor.
The next day as I was leaving the marina when in reverse and with the main sail up suddenly the engine
began to accelerate and white smoke came out of the exhaust
. It lasted for 5 to ten seconds. I was able to put it in neutral and shut it down. But the boat ended up on a reach sailing into the marina in a channel with slips on both sides and a concrete wall at the end.
By pure coincidence a friend had seen the whole thing and jumped from another sailboat. As I ran to lower the main he steered the boat and my wife looked after the girls. I was able to lower the sail but of course the boat was slowly moving towards the leeward docks full of boats. We decided to turn on the engine
and were able to stop the boat and get enough reverse movement to put it in the slip. But it did runaway again for lets say 10 - 20 seconds intermittently. During the event rpms went up to 3000 but it never overheated. There was about a quart of an oil/fuel mix under the engine. Tracing it it seems like the oil came out of the valve cover cap.
After checking everything out I found that the injection pump was leaking badly into the engine through its main shaft. I removed 2.8 gallons of oil/fuel mix from the engine. Don't ask me why I didn't notice the high level oil in the dipstick. I guess there was so much diesel
that the dipstick would drain and by the time I looked there was only fuel
in the tip.
At this moment I have installed the rebuilt TAD fuel injection pump and engine runs great except for rpm's under load won't go past 2500 rpm. Clean propeller, freely turning shaft, it won't even smoke under load at full throttle. In neutral it revs up to 3800 rpm. In the past with the old pump under the same conditions it would rev up to 3000 rpm under load tied to the dock and black smoke would come out of the exhaust. Any ideas?