Hello -- humbly seeking your advise / insight here....
Symptom: (2004 FourWinns, Penta 5.0GL) opening throttle (not slamming it) and accelerating the boat to above +3000 rpm (approximately), the engine hesitates, it fails to gain power, and I hear what appears to be backfiring under the hood. If I back the throttle, most of the times the engine will recover; if I stay on it - the engine dies.
I first noticed this last year, towards the end of the season. A year before that they replaced the distributor cap. I brought the boat to the dealer to be serviced, and they told me that the carb is gunked up and needs rebuilding. By the they were done it was too late for a lake test, they winterize the boat and asked me to bring it back this spring to test it. They had the boat for 3 weeks (!!!) before they got around to lake-test it. The problem was still there. They said that under high-power demand the engine becomes "starved for fuel", so the low-pressure fuel pump needs to be replaced. They could only get the pump the following week, and it will be a total of $500 (let's not forget the $450 carb rebuild...). I was quite upset that it took them that long only to come up with this diagnosis, so I took the boat home, ordered a pump and installed it myself.
Yesterday I put the boat in the water only to find out that I'm back to square one -- engine still misbehaves... :grumpy:
Could it still be the pump? Is there a simple way to test that pump? Could it be an ignition issue? Timing? Plug cables? How should I proceed troubleshooting this?
Any advice from this collective brainpower will be highly appreciated!
Frustrated in Michigan,
Zevi.
Symptom: (2004 FourWinns, Penta 5.0GL) opening throttle (not slamming it) and accelerating the boat to above +3000 rpm (approximately), the engine hesitates, it fails to gain power, and I hear what appears to be backfiring under the hood. If I back the throttle, most of the times the engine will recover; if I stay on it - the engine dies.
I first noticed this last year, towards the end of the season. A year before that they replaced the distributor cap. I brought the boat to the dealer to be serviced, and they told me that the carb is gunked up and needs rebuilding. By the they were done it was too late for a lake test, they winterize the boat and asked me to bring it back this spring to test it. They had the boat for 3 weeks (!!!) before they got around to lake-test it. The problem was still there. They said that under high-power demand the engine becomes "starved for fuel", so the low-pressure fuel pump needs to be replaced. They could only get the pump the following week, and it will be a total of $500 (let's not forget the $450 carb rebuild...). I was quite upset that it took them that long only to come up with this diagnosis, so I took the boat home, ordered a pump and installed it myself.
Yesterday I put the boat in the water only to find out that I'm back to square one -- engine still misbehaves... :grumpy:
Could it still be the pump? Is there a simple way to test that pump? Could it be an ignition issue? Timing? Plug cables? How should I proceed troubleshooting this?
Any advice from this collective brainpower will be highly appreciated!
Frustrated in Michigan,
Zevi.
