I broke the engine down last night. I took off the oil pan/intake and exhaust manifolds, expecting to find water, sand, in engine/like all junkyard engines. I was shocked! Engine was clean inside!!Oil was fresh. Stopped disaasembly at that point. No water or dust. Taking borescope shots today of pistons/ rings.
My intuitive feeling is that an engine like this is better left alone.Its a running engine. One could actually do more harm than good by rebuilding it unless one is a Mercedes pro because of the myraid specs and tolerances that must be done tediously when rebuilding.
I have a strong urge to (1) clean it, stop there and put it back together and run it. Car I took it from had approx. 150,000 miles.
or (2) Head Job, New Piston Rings/Oil Rings, Oil Pump What are your thoughts?

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