Prime the fuel pump?

[litespeed999]

Hi all-

I have a 240 Overnighter with the 7.4 454 Mercruiser. Having a problem with engine sputtering and losing power under load. Took it out for our first time after bringing out of storage. Boat fired up and revved fine in driveway, but when out on the lake, throttling up under load would cause the motor to pit and sputter and lose power. Couldn't even get the boat up on plane.

First thought was bad fuel; drained tank, replaced with fresh fuel, installed new fuel filter. Now motor won't start at all. Cranked it would long time, but no fuel is getting to the motor. Pulled fuel filter back down and filter was dry. Tried filling fuel filter to help "prime" the pump, but still no start, just crank.

I'm not great with engines, so I'm trying to understand how the fuel pump works. The fuel pump is after the filter and is not electric, so its mechanical, correct? Does the pump need to be primed somehow to get it going?

If I can't figure this out soon, I'm just going to have to take it to SR mechanic.

Any help would be appreciated

Lite

 

[litespeed999]

Might have resolved my issue. Poured a bit of gas directly into the carb throat and started it up. It fired up for a sec then stalled out. Did it again and this time it didn't stall out! It kept running! So I guess I did need to prime the fuel system to get it going. I found a fuel leak in the line from the filter to the pump, but I probably caused that when taking the line off to remove the fuel filter assembly.

Next stop after I fix the fuel leak is to test it out on the lake. Hopefully replacing the fuel and fuel filter solves my engine problem