This is a ranch truck and has seen lots of hard miles, 170,000 but who only knows how many hours on the engine. I ran good all day, would smoke a little the next morning but no start. Then it quit smoking so we tried to pull start it with no luck. Tried to pull start it today, have good oil pressure, drained the fuel bowl and diesel is pumping in while cranking. I am out of ideas of what to try next, thanks in advance