ZD25 Power Loss

[juicybusa]

2006 ZD25 loses power and will actually die if deck is not disengaged when there is 2-3 gallons left in tank. Add fuel/full power. Common sense would say a cracked fuel pick-up but local dealer says he's never seen this and that the fuel pickup is non-replaceable-must replace entire tank assembly. Don't want to buy a tank if I'm not certain. Should the fuel pump stop with the key on/engine off when proper pressure is reached??? pump seems to run continuously with key on/engine off. Seems a bit stange. Any assistance or ideas are welcome-thanks