25 hp motor bogs down after running great for about 300 yards.cut off engine and let sit about 5 min

[wayne webster]

after running perfectly about 400 yards

 

[racerone]

Model # ??-------How long have you owned it ?------Have you replaced / inspected waterpump impeller ?------Any other history on the motor ?------------Any other maintenance done ?----Mixing gas and oil at 50:1 ??-------Tank vent checked ?