Rejuvenating a sick engine
So now that the valve stem seals, and actually every seal and gasket has been changed on this N62, together with a whole cooling overhaul (including a collapsible pipe, WP, belts, pulleys etc), new rear ball joint & air suspension, and a slew of other stuff, I decided to do a hot oil flush, then drop the oil pan and clean it if any residues are found. When I checked the oil, and when I worked to change the stem seals, the engine didn't looked to bad, but after running the Lubro-Moly engine flush, the oil came out black like tar, not that dark brown.
I also found some hard "beans" that looked like kidney stones inside the oil sump. Below is the pic. Does anybody know what these might be, and how they are formed? They feel very hard and look like little rounded off stone chips....
Also, the dipstick is made out of 2 parts, and they join together at the lower valve cover level, so one can swivel it if you have to change the VCG. The swiveling part just disintegrated, so I had to change the lower dipstick guide. Just heads up FYI, it's quite a bear to remove that dipstick guide, just because it's hold in place by a lockdown plate at the bottom. The 10mm nylock is in a very tight place, and you need a stubby small ratchet to fit there, and even then, it's quite hard going. You do it by feel, no visual. Actually if you have visual, you can't work. If you work you have no visual. You know what I mean. The O-ring was also bust, it was all flattened and didn't seal anymore. I tried re-using that one, but the new dipstick guide fell right through it... To remove the O-ring, you HAVE to take off the lower oil pan, and push it up through the dipstick guide hole. Impossible to take it out otherwise. But back to my question: does anybody know how one could end up with "kidney stones" in the oil pan? What the heck are those and how are they formed? (wrong oils used by the PO maybe?)
http://i380.photobucket.com/albums/o...ps8cd64cb5.jpg |
