I recently purchsed my first fishing boat, an 87 GW Trophy Pro, and the Aux tank is the only one I can use. When ever I switch the engines to the main tank the port engine ball pump starts to freeze up a little and won't run, the starbord engines ball pump completely freezes ( stays collapsed ) up and is getting no gas at all. As soon as i switch the levers back to the aux tank the ball pumps release and I am able to give them a few pumps to start the engines off of the aux tank.

Can anyone help?

THANKS!!

Something blocked between valve and tank. Check valve, lines, antisiphon valves, pickup tubes in tank, filters and tank vent.

Agree something is blocking the pickup or the tank vent is blocked.

Will the main tank work if the gas cap is removed?

I have seen dirt dobbers block tank vents and bilge pump lines

No, the main tank will not work with the gas cap off.

Do I remove the floor board plate and then remove the cap to the main tank where the fuel lines come out to see the "pickup"??

Thank you for your help!!

You could remove the gas cap and remove the fuel line at the select valve, see if you can blow back through the line with a little amount of compressed air like 5 psi, if you hear air bubbling in the tank then it was something stopping the pickup.

Be sure to remove the tank gas cap first or you may damage the tank with the air pressure.

Make sure that there are no ignition sources present.

Thank you! I will reply this weekend when I get back to Charleston to try and work this out!

Try this first. Switch to the main tank and dicconnect the fuel line on the tank side of the ball. Pressurize it slightly with some air. With the cap on the tank you should hear bubbling in the tank and get some air out of the vent. If there is something clogging the pick up this might dislodge it. If you get nothing I would start with making sure the valve is switching all the way. Both your engines pull fuel from one tank pick up? Just my 2ct's worth.