Hoping someone can provide me some guidance with regard to a 1990 Yanmar 3 cylinder engine on my PSC 34.
At the beginning of the season the engine experienced a sudden reduction in power. In response, I changed the fuel filter and Racor filter and bled the engine, which seemed to alleviate that symptom. A month later I experienced a sudden complete loss of power in the middle of Lake Michigan (with no wind). I could not get the engine to turn over and was towed into a Michigan harbor. The following day the engine started right up. I had the fuel examined--it is clean. The mechanic I hired in Michigan failed to diagnose any problem.
In a good stiff wind, I sailed the boat back to Chicago and was able to keep the engine going at a low RPM in order to make it into my slip. I then called Crowleys, a well known boat yard in Chicago. Crowleys replaced the fuel pump and said it fired right up. It did fire right up, followed by sudden reduction in power under load. The third mechanic I hired replaced the fuel pump that Crowleys had installed with an anti-siphon pump, which improved all symptoms.
However, problems persist. When under load, the engine is not very responsive to the throttle. I will give it some gas and the engine will act as if it is about to die, but then accelerate after several seconds. This afternoon, while in the Calumet River on my way to winter storage, the engine was completely unresponsive to the throttle and felt as if it was about to die at lower RPMs. At higher RPMs under both engine and sail, the engine hummed right along.
My next step (I think) is to replace the fuel injection pump. Any insight or suggestions would be appreciated!
At the beginning of the season the engine experienced a sudden reduction in power. In response, I changed the fuel filter and Racor filter and bled the engine, which seemed to alleviate that symptom. A month later I experienced a sudden complete loss of power in the middle of Lake Michigan (with no wind). I could not get the engine to turn over and was towed into a Michigan harbor. The following day the engine started right up. I had the fuel examined--it is clean. The mechanic I hired in Michigan failed to diagnose any problem.
In a good stiff wind, I sailed the boat back to Chicago and was able to keep the engine going at a low RPM in order to make it into my slip. I then called Crowleys, a well known boat yard in Chicago. Crowleys replaced the fuel pump and said it fired right up. It did fire right up, followed by sudden reduction in power under load. The third mechanic I hired replaced the fuel pump that Crowleys had installed with an anti-siphon pump, which improved all symptoms.
However, problems persist. When under load, the engine is not very responsive to the throttle. I will give it some gas and the engine will act as if it is about to die, but then accelerate after several seconds. This afternoon, while in the Calumet River on my way to winter storage, the engine was completely unresponsive to the throttle and felt as if it was about to die at lower RPMs. At higher RPMs under both engine and sail, the engine hummed right along.
My next step (I think) is to replace the fuel injection pump. Any insight or suggestions would be appreciated!