Jay Nelson
New member
I have at 1999 Silverton 392 Motor Yacht with Crusader 5.7 MPI (454 TBI) engines. I have owned the boat since it was new, have always been meticulous with regular maintenance, and these Crusader 5.7 MPI engines have provided excellent service for twenty years.
In the fall of 2019, the engines had over 2,300 hours on them. As the general consensus was I was nearing the expected life of these engines, I decided to have these engines rebuilt as a precaution in preparation for a year-long trip on the Great Loop. During the engine rebuild we installed new Parker S3227, 10-micron, marine fuel/water separator filters on the bulkhead, bypassing the factory Racor 110a filters (filter bodies left in place, with elements removed) mounted on the engines because the starboard filter was very difficult to service.
Unfortunately, what was planned to be a winter 2020 project took over two and a half years due to COVID-19 and resulting supply chain problems. During that time, approximately 200 gallons of fuel sat in the tanks and the ethanol in the fuel phase separated. After the engine rebuild was completed, we understandably had contaminated fuel problems. A fuel enzyme was added to the tanks, allowed to sit for a week, and then pumped dry. New fuel was added and polished. Approximately five months later, because we were changing filters so often, we had a second Parker S3227 filters added to both engines with bypass valves to prevent getting stranded.
Our problem is we have never been able to get past what appears to be a fuel contamination issue, especially because our problem affects both engines. In the last ten months, we have run over 3,300 gallons of fuel through these engines and had to replace twelve sets of filters, and the problem is becoming more frequent.
The symptoms are always the same, typically beginning with the starboard engine, followed by the port engine. Cruising at 1600-1800 RPM for a period of time ranging anywhere from three to six hours, the RPM will initially drop by a couple of hundred RPM, e.g., from 1600 to 1400, and then bounce back to the cruising RPM. After ten to fifteen minutes, it will happen again. Over a period of time, sometimes an hour or longer, the RPM dropout gradually becomes more pronounced, e.g., from 1600 to 850 (idle RPM), and occurs more frequently, to the point where the engine RPM fluctuations make the engine inoperable. Changing the fuel filters ‘resets’ the problem and the engines will run for three to six hours again.
We have now had the fuel in the tanks polished three times since the contaminated fuel was removed. Each time the fuel technician has found some level of water or debris contamination in the fuel, but acknowledged this could just be the normal fuel we are getting form various marinas. We have had five mechanics onboard, all recommended by local marinas as certified gasoline engine repair technicians, who have tried different solutions, but the problem persists. We have also had a corrosion expert examine the aluminum tanks and have been assured there is no internal corrosion that might be causing the problem. Any ideas as to what I might try to fix this issue?
In the fall of 2019, the engines had over 2,300 hours on them. As the general consensus was I was nearing the expected life of these engines, I decided to have these engines rebuilt as a precaution in preparation for a year-long trip on the Great Loop. During the engine rebuild we installed new Parker S3227, 10-micron, marine fuel/water separator filters on the bulkhead, bypassing the factory Racor 110a filters (filter bodies left in place, with elements removed) mounted on the engines because the starboard filter was very difficult to service.
Unfortunately, what was planned to be a winter 2020 project took over two and a half years due to COVID-19 and resulting supply chain problems. During that time, approximately 200 gallons of fuel sat in the tanks and the ethanol in the fuel phase separated. After the engine rebuild was completed, we understandably had contaminated fuel problems. A fuel enzyme was added to the tanks, allowed to sit for a week, and then pumped dry. New fuel was added and polished. Approximately five months later, because we were changing filters so often, we had a second Parker S3227 filters added to both engines with bypass valves to prevent getting stranded.
Our problem is we have never been able to get past what appears to be a fuel contamination issue, especially because our problem affects both engines. In the last ten months, we have run over 3,300 gallons of fuel through these engines and had to replace twelve sets of filters, and the problem is becoming more frequent.
The symptoms are always the same, typically beginning with the starboard engine, followed by the port engine. Cruising at 1600-1800 RPM for a period of time ranging anywhere from three to six hours, the RPM will initially drop by a couple of hundred RPM, e.g., from 1600 to 1400, and then bounce back to the cruising RPM. After ten to fifteen minutes, it will happen again. Over a period of time, sometimes an hour or longer, the RPM dropout gradually becomes more pronounced, e.g., from 1600 to 850 (idle RPM), and occurs more frequently, to the point where the engine RPM fluctuations make the engine inoperable. Changing the fuel filters ‘resets’ the problem and the engines will run for three to six hours again.
We have now had the fuel in the tanks polished three times since the contaminated fuel was removed. Each time the fuel technician has found some level of water or debris contamination in the fuel, but acknowledged this could just be the normal fuel we are getting form various marinas. We have had five mechanics onboard, all recommended by local marinas as certified gasoline engine repair technicians, who have tried different solutions, but the problem persists. We have also had a corrosion expert examine the aluminum tanks and have been assured there is no internal corrosion that might be causing the problem. Any ideas as to what I might try to fix this issue?
