hey guys, i recently purchased an old (not sure how old) kubota t1400 hst lawn tractor. it was running fine a few days ago (still in the posession of the previous owner) he cut the grass, then a few days later, power washed it to clean it up before i looked at it. now it will only start if its hooked up to a booster/charger box or a vehicle for a jump. it will run for 5 mins or so, then die. starter will crank the engine, but fairly slow. tried a new battery already with the same result...any help or ideas would be apreciated