Greetings. Iíve been a lurker on the forum for several years and often find helpful information. Now I have an engine issue for which I havenít found a thread that seems to match my exact symptoms.
I have a 1974 30í Willard Vega with the original Perkins 4-107 diesel. Iíve had this boat for 3 years, and before that had a couple of sailboats.
Recently my engine RPMs started to creep up without me touching the speed lever (throttle). Yesterday, I was running for about 20 minutes at 1500 rpm and it increased to about 3000 rpm within 5 seconds. It shut down immediately with the kill switch. I started it up again and it did the exact same thing. I couldnít bring the RPMs down short of stopping with the kill switch.
The engine always starts immediately and without any smoke. When cold, the engine will idle at about 800-1000 rpm for many minutes without issue.
An interesting symptom is that, at idle, when I pull the speed lever down hard the RPMs increase, and if I then push up a tad the RPMs go down again. I wouldnít expect the RPMs to increase when the lever is pulled all the way down.
The little shaft on the fuel injection pump seems to rotate fully back and forth when the speed lever is moved up and down.
The uncontrolled increase in RPMs seems like what Iíve read as Ďengine runawayí but Iíve read that that condition is very rare and often requires some other fuel source (like oil in the diesel, or diesel in the oil?), and that the kill switch wonít immediately stop the engine.
So a couple of questions:
- Is there already a Trawler Forum discussion thread that matches my symptoms?
- How do I diagnose the root problem?
- Any suggestions for knowledgeable mechanic/shop in the Seattle, Tacoma, Olympia area? (Preferably one that wonít spend a few thousand of my precious boat bucks before finding the problem.)
Lastly, I have to give kudos to Boat U.S. towing which turned a potential disaster on the water into a mere inconvenience.