Engine is 70TLEND outboard from Evinrude vintage 1992 with 3 cylinders. Installed on Pontoon 24' boat with built-in tank and atwood breather vent in side of pontoon (clean screen). New VRO pump (twice - last year and this year) new fuel filter clean and full of fuel - oil sight is also full. Oil tank new and full - sensor working new oil line to fitting at engine. Both bulbs firm all the time. Plugs ok - new last year showing brown residue, but not out of line.<br /><br />Problem: Starts ok, slightly hard, but runs immediately at smooth idle when first boarding for the day. MOves the pontoon up the river and to the lake at all speeds smoothly and effortlessly. Once anchored for 1 hour or two hours, motor will NOT start and fuel bulb is firm, no restrictions noted, filter is full of fuel. Choke/primer on or off does not matter. Excessive cranking required (burned up the battery cable on this one last night!). <br /><br />Eventually, the motor will sputter and show some life and then start and run fine all the way back to the dock/lift.<br /><br />What would cause this condition? vapor lock - never happened before? When it does run, all is quite good - smooth, powerful (moves pontoon at 25 to 28 MPH on pitot-tube speedo).<br /><br />Thermal expansion problem in charge coil? Other weird electrical system problem? Have you heard of this before? How can the motor run so well when it does and then just not want to start?<br /><br />David.
