Mercruiser 5.0 W/Rochester Carb Dies After running low speeds

[THenning]

Hi All,

Need some suggestions here.

1978 Mercuiser 5.0 (model 228) with Rochester Quadrajet.
Carb was rebuilt 2 seasons ago with ultrasound bath
Fuel Filter new as of last season, Fuel/Water Separator same (new as of last season)
Mechanical Fuel Pump with Sight glass (looks original)
Removed Anti-Siphon Ball at Marina's suggestion last week when talking to them.

Problem:
Runs Fine At 4200 RPM/Up on plane. I live on a chain of lakes, after running through a channel at idle it will die when I open the throttle up. One or twice it died in channel before opening throttle up.

Sometimes if I ease the throttle up to WOT it will sputter for 30 seconds and then seem to "clear out" and go.

If it dies in channel it takes A LOT of starting to get going again.

Revs in neutral fine even when it does going into gear, but won't stay over 3k for long in neutral before acting fuel starved again.

Blower motor is kept on 100% of the time through channel. Engine temp is ~110-115


Question:
Should I be rebuilding the carb again? Trying to replace the 70's fuel pump? Replacing the fuel filter?

Thanks so much for your insights.

Tim

 

[alldodge]

Need to find out if your getting to much or to little fuel. When it dies is there fuel dripping down the throat of the carb or is it dry. If dry, when the throttle is pumped does any fuel squirt down the carb?

 

[THenning]

Triggering the accelerator pump sometimes will keep it alive by squirting fuel in, I will check if the throat of the carb is starved or not. Hard to get it to do this in driveway and when it happened last didn't have a wrench to remove the intake flame arrestor.