06-06-2007, 11:22 PM
"Recently replaced my 5.0LGM 190hp (500A Volvo Duoprop) with a new 5.7L (300hp) Indmar Vortec engine with a holley 4bbl. carb. The result is less power, lower RPM, half the old speed, and failure to start normally afer running. Must be primed and choked every time. I was told by volvo that a prop change wasn't necessary. The lower RPM could be due to fuel delivery and carb problems. The new engine is sick. I thought maybe old fuel initially but all new fuel and same problem. Any ideas would be greatly appreciated. Thanks"