1985 Mercury 25XD Bogs under load Need Help Please

1985 Mercury 25XD

When I first start the boat it runs fine for a few minutes wide open
then without warning motor quits at full throttle
will restart fine and runs normal to 1/4 throttle then any more throttle it just bogs down and won't go any faster
if I let it sit for 10-15 minutes, it will start fine and run normal full throttle for about 15 sec then starts rapidly losing power and then will run at 1/4 throttle again

Carb was rebuilt and I replaced Tank, all fuel lines, bulb, filter about 5 tanks ago

Any ideas?

Thank you in advance

Sounds like a weak fuel pump. Pump the bulb next time it does this and see if that helps.

Jeff

Fuel pump is in carb.....check to see if its dropping a cylinder when it does this.