I've had the boat about a year, 1990 31' Tiara. It has a small 12V, 3 GPM FW supply pump. Since I've had it the pump cycles about once an hour. When I open a faucet it flows good for about 10 sec then down to a trickle. Gets wore and worse. I replace the pump yesterday (shurflo). It's a little better but still only flows strong for about 10 - 15 sec. Could it be a clog in the supply line?