If the cars dredged up sludge from the bottom of the tank there could be a blockage in the fuel lines possibly? Fuel pump given up another possibility.
Could even be your starter motor and nothing to do with the fuel. Do you just get a clicking sound when you turn the ignition? if so its the starter motor, but if it still turns over (although it sputters to a stop) it could be pretty much anything fellah, alternator leads, sparks etc etc
If its been left standing for a long period before you took ownership the battery may be low on charge. Maybe check your battery connections are not loose, eliminate the obvious things.
Hope you sort it though,
Linda
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