When trailering the boat, the water sloshing around could create a back pressure into the manifold thus killing the flow and the motor just buzzing.
Quote When trailering the boat, the water sloshing around could create a back pressure into the manifold thus killing the flow and the motor just buzzing.The pump is in the bilge so we know you have good suction head... The MFG said is a must to mount the pump vertical to prevent issues with the getting air bound. Makes sense if the little air inducer is at the eye of the pump. I was thinking it was on the outflow in a venturi so didn't consider that as an issue, my apologies. If you fix the pump mounting position before you do/change anything else you may find that life is again good.. Hopefully you can just loosen a clamp or two and yard the thing vertical to test the theroy, keep it simple first, if that doesn't work then get out the hammer...As a standing member of the "not very guardedly skeptics club".. I don't by "a dip in the suction line" to be much of a causal factor because the pump is BELOW its suction source.. Does the trap in your sink ever get air bound