Hi folks. I'm new to the forum and was hoping for some insight to a problem I'm having. My boat/eng info:
2005 Regal Destiny 2120
Volvo Penta GXi / SX Outdrive
Eng SN 4012129594
Have been running the boat most weekends since April this season without fail. In particular, on our last outing (about three weeks ago) we had done some tubing (for the first time this season) and cruising without fail. Took the family out on the water two weeks ago and the boat would not accelerate enough to get up on plane. I noted RPM was limited to about 2500 RPM with all other indications normal. This was under a load of roughly 700 lbs (4 adults, 2 dogs). I brought the boat back into the marina and pulled/drained the fuel filter and didn't note anything significant at the time. Restarted and was able to accelerate to normal engine RPM speeds in neutral but upon taking boat out on the water once again (under reduced load of two adults) I was once again RPM limited. Prop was noted to be spinning freely with outdrive disengaged. We ended up putting the boat back up without any further significant troubleshooting.
After reading through some older threads on this forum I thought I might have an issue with paint flaking clogging up the fuel pump(s). I have been using regular unleaded fuel (with ethanol) with a consistent SeaFoam or Stabil mix and thought I may be experiencing the paint flaking within the fuel pump described in those threads. I went back out yesterday to test the fuel system and found some evidence of black paint flakes upon re-draining the fuel filter. I didn't have a new filter with me so I simply drained and flushed with fresh gas the best I could. I also removed the fuel pressure regulator valve and noted residue on the intake screen. I was able to clean the screen with carb cleaner followed by gasoline rinse and it looked good and was reinstalled. Ran a test on the fuel pump output and noted 12 psi at the low press pump and 60psi idle/50psi WOT from the high press pump. These readings are normal as I understand it. I took the boat out with just me aboard (210 lb load) and this time was barely able to get up on plane and, once on plane, only maxed out at 3300rpm WOT. Pressure on the high press pump remained at roughly 50psi throughout throttle range.
With the drive in neutral I have no problems accelerating to normal RPM, it's only under load where it seems to bog down or become limited.
I had changed the fuel filter last fall during winterization so didn't think to bring another filter with me for testing. I'll be picking up a new filter today to check that potential problem off the list. I'm now thinking the problem lies at the fuel injectors themselves or the motor is being limited by the computer for whatever reason. All indications from the cockpit appear in the normal ranges.
Am I missing something? I'm relatively new to boat maintenance but am capable on cars/motorcycles, especially with a little youtube coaching. I'd like to try and fix this myself if I can but am afraid I've got some sort of engine limiting going on within the brain of the computer. I'd appreciate any insights or recommendations from the brain trust here!
Thanks in advance for any help you can offer.
2005 Regal Destiny 2120
Volvo Penta GXi / SX Outdrive
Eng SN 4012129594
Have been running the boat most weekends since April this season without fail. In particular, on our last outing (about three weeks ago) we had done some tubing (for the first time this season) and cruising without fail. Took the family out on the water two weeks ago and the boat would not accelerate enough to get up on plane. I noted RPM was limited to about 2500 RPM with all other indications normal. This was under a load of roughly 700 lbs (4 adults, 2 dogs). I brought the boat back into the marina and pulled/drained the fuel filter and didn't note anything significant at the time. Restarted and was able to accelerate to normal engine RPM speeds in neutral but upon taking boat out on the water once again (under reduced load of two adults) I was once again RPM limited. Prop was noted to be spinning freely with outdrive disengaged. We ended up putting the boat back up without any further significant troubleshooting.
After reading through some older threads on this forum I thought I might have an issue with paint flaking clogging up the fuel pump(s). I have been using regular unleaded fuel (with ethanol) with a consistent SeaFoam or Stabil mix and thought I may be experiencing the paint flaking within the fuel pump described in those threads. I went back out yesterday to test the fuel system and found some evidence of black paint flakes upon re-draining the fuel filter. I didn't have a new filter with me so I simply drained and flushed with fresh gas the best I could. I also removed the fuel pressure regulator valve and noted residue on the intake screen. I was able to clean the screen with carb cleaner followed by gasoline rinse and it looked good and was reinstalled. Ran a test on the fuel pump output and noted 12 psi at the low press pump and 60psi idle/50psi WOT from the high press pump. These readings are normal as I understand it. I took the boat out with just me aboard (210 lb load) and this time was barely able to get up on plane and, once on plane, only maxed out at 3300rpm WOT. Pressure on the high press pump remained at roughly 50psi throughout throttle range.
With the drive in neutral I have no problems accelerating to normal RPM, it's only under load where it seems to bog down or become limited.
I had changed the fuel filter last fall during winterization so didn't think to bring another filter with me for testing. I'll be picking up a new filter today to check that potential problem off the list. I'm now thinking the problem lies at the fuel injectors themselves or the motor is being limited by the computer for whatever reason. All indications from the cockpit appear in the normal ranges.
Am I missing something? I'm relatively new to boat maintenance but am capable on cars/motorcycles, especially with a little youtube coaching. I'd like to try and fix this myself if I can but am afraid I've got some sort of engine limiting going on within the brain of the computer. I'd appreciate any insights or recommendations from the brain trust here!
Thanks in advance for any help you can offer.
