VolvoPenta/OMC Ford 5.0L Stalls at medium/high speed

[DarenFourWinns190]

1995 Fourwinns Horizon 190 Sterndrive.

I just installed a crate long block from ATK (including new fuel filter/water separator). The boat starts and runs great, but after some time 30 minutes/1-1/2 hours it stalls when medium to high speed. Motors sounds as if it is out of fuel. The motor always restarts, usually need to 'pump' the throttle two times and start with throttle open. It will cruse at 10 mph continuously without any issue.

Since experiencing this issue, I have: Emptied, removed and cleaned fuel tank (there was some small particles and a few drops of water), replaced mechanical fuel pump, new coil, cleaned carb bowl, float needle and carb inlet screen. Everything looked good and clean.

Next I will replace the fuel filter/water separator, but I'm just about out of ideas.

 

[DarenFourWinns190]

I should mention during the engine replacement I installed new plugs, spark plug wires, distributor cap & rotor.

 

[Scott Danforth]

start with the basics...... what is your fuel pressure?

when you had the carb out to clean the bowl, did you chase all the passages with a fine wire to make sure they are clean, or did you just spray carb cleaner in the bowl and pray?

 

[DarenFourWinns190]

Sounds like good next steps.

Not sure how to test fuel pressure. There is a hard tube from pump to the carb. Is there a place I can tap in with my fuel pressure gauge?

Just soaked and blew the passages on the carb. I'm familiar with single piston motorcycle carbs. I just don't know the passages. Is there a reference or details on how to trace the passages?

 

[kenny nunez]

There may be a small fine filter inside of the suction tube in the tank which will clog easy.