when my boat engine is cold it will start fine but get the engine hot ,it will not start,as though batteries have gone flat.Allow the engine to cool and it start fine again.
Engine 4.2 Yanmar diesel
I like John's answer and make sure you are not running tooooo hot!! Also could be a starter solenoid. Make sure you have clean positive cable connections and grounds. Resistance will also increase in these areas as heat and demand increases.
Frank, February 2008
More than likely to be the starter motor itself - like the engine, it too gets hot and this is when the windings start to fail.
