eastwardexpansion
New member
Hi All,
I have a BF40D that is having a peculiar problem that I cannot figure out. This is an intermittent issue that is becoming more prevalent. After running for a period of time (quite brief if at WOT) the engine will begin to bog down and bounce off of 4k RPMs. This is a rather long duration and quite aggressive die down and then surge up towards 4k before then repeating this process. Another condition is if the boat is idled for long enough it will die and refuse to restart. This results in a crank, no-start condition. The boat can be restarted (sometimes) by cycling the key and waiting multiple times to increase the fuel prime. This leads me to believe it is something on the high-pressure side of the fuel system.
Motor:
BF40D (BBDJ-110XXXX)
~2015 outboard
2600 hours
This boat is a Zodiac Pro 420 for a sailing organization. These boats accrue around 300 running hours a year. These are hard hours with lots of acceleration and the boats are really either in displacement mode or at WOT. Lubricants, plugs, and water separators are replaced at least twice a year (seasonal program); however, that is about it. Don't roast me, I have just become the one making the decisions about out maintenance.
Current diagnostics:
- Fuel water separator is new and not restrictive
- Internal fuel strainer is clean
- Primer bulb is hard and full of fuel
- No air seen in either filters (have not hooked up using clear tubing)
- Replaced VST filter which was absolutely disgusting (borderline black)
- Drained VST multiple times and it was clear and clean fuel
- Happens regardless of engine temp so does not seem to be thermostat/impeller related
Things I am wondering about...
- Is my next step to rebuild the VST?
- Are there any internal filters on the VST that could be clogged?
- Could this be injectors?
- Anything else I am missing?
Any help would be greatly appreciated.
I have a BF40D that is having a peculiar problem that I cannot figure out. This is an intermittent issue that is becoming more prevalent. After running for a period of time (quite brief if at WOT) the engine will begin to bog down and bounce off of 4k RPMs. This is a rather long duration and quite aggressive die down and then surge up towards 4k before then repeating this process. Another condition is if the boat is idled for long enough it will die and refuse to restart. This results in a crank, no-start condition. The boat can be restarted (sometimes) by cycling the key and waiting multiple times to increase the fuel prime. This leads me to believe it is something on the high-pressure side of the fuel system.
Motor:
BF40D (BBDJ-110XXXX)
~2015 outboard
2600 hours
This boat is a Zodiac Pro 420 for a sailing organization. These boats accrue around 300 running hours a year. These are hard hours with lots of acceleration and the boats are really either in displacement mode or at WOT. Lubricants, plugs, and water separators are replaced at least twice a year (seasonal program); however, that is about it. Don't roast me, I have just become the one making the decisions about out maintenance.
Current diagnostics:
- Fuel water separator is new and not restrictive
- Internal fuel strainer is clean
- Primer bulb is hard and full of fuel
- No air seen in either filters (have not hooked up using clear tubing)
- Replaced VST filter which was absolutely disgusting (borderline black)
- Drained VST multiple times and it was clear and clean fuel
- Happens regardless of engine temp so does not seem to be thermostat/impeller related
Things I am wondering about...
- Is my next step to rebuild the VST?
- Are there any internal filters on the VST that could be clogged?
- Could this be injectors?
- Anything else I am missing?
Any help would be greatly appreciated.