From your description, it doesn't sound like major engine problems, 'tho I could be totally wrong - I'm totally unschooled in mechanics, just experience and common sense. If it comes and goes, as you described, that is actually a good sign. SERIOUS engine problems will just come and STAY! Is there any smoke or oil leaks associated with this noise?? Both bad signs, of course. Internal engine problems (rods, crank, pistons, rings, valves, etc) will definitely let you know - by smoke, distinct noises (heard rods knockin' many times), oil leaks, gauges, engine locking up
etc, etc. Wish you luck......hopefully someone here will offer more help.
mechanically challenged mud
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