90 Smokercraft with 40hp Evinrude getting water in tank?

First post for me as just bought my first boat...(Yep the first of the only 2 happy days of boat ownership is done...lol).
Anyways, when I bought it they thought that water was somhow getting into the gas tank even though they had drained/cleaned it. This is a regular 40hp VRO motor with a water seperator. They thought it went from 1/2 tank to almost 3/4 when the hooked water up to it and ran it.
Question: Is there any way possible this can happen, and if so...how and what is a fix?
Thank you all...
Mac

Re: 90 Smokercraft with 40hp Evinrude getting water in tank?

If you determine your fuel by the fuel guage,you must read it with the boat in same plane all the time for best accuracy.simply ,if you have it on a trailer and jack the trailer up or down,your reading could be quite different,it works by a float in the tank,and the gas shifts depending on the attitude of the boat.As for the water,if it is getting water in ,it could be a faulty vent for the tank ,or a seal on the gas cap leaking ,during rain .make sure your vent isnt getting hit with spray as you run,in addition it shouldnt allow water in if properly places and plumbed to the tank.

Re: 90 Smokercraft with 40hp Evinrude getting water in tank?

If you determine your fuel by the fuel guage,you must read it with the boat in same plane all the time for best accuracy.simply ,if you have it on a trailer and jack the trailer up or down,your reading could be quite different,it works by a float in the tank,and the gas shifts depending on the attitude of the boat.As for the water,if it is getting water in ,it could be a faulty vent for the tank ,or a seal on the gas cap leaking ,during rain .make sure your vent isnt getting hit with spray as you run,in addition it shouldnt allow water in if properly places and plumbed to the tank.Fuel guages are not exact.Never lrt them go below 1/4 tank

Re: 90 Smokercraft with 40hp Evinrude getting water in tank?

Thank you MikeSea...