View Full Version : 57l Gsi Volvo Penta 1999 Backfires around 3000rpm

Jason Hughes
06-12-2006, 11:34 PM
I have had my boat for 4 years now with no problems until a few months ago. This problem always happens when the motor is warm after sitting for a while. I can start the boat and accelerate through 3000rpm and past to around 3200rpm and cruise with no probs but when the RPM drops to around 2800-3000rpm the motor will backfire about every 20 seconds if held in this rev range. There are no signs of any other issues with the motor. Help??

06-19-2006, 08:21 AM
"Backfiring is caused by a lean out condition. You're not getting enough gas to the carb (assuming it has one). Change the fuel filters and drain the water separator (if it has one. If not, add one! Marina gas has water in it regularly.)


Jason Hughes
06-23-2006, 04:59 AM
"Thanks Jeff, I have changed the fuel filters and drained the the gravity separator and still have the same result. This is an injected model. I have new leads, rotor & plugs that I will fit this weekend."