I did an oil change on the 603 today. However, this time I took PEH advice and cracked the lower oil cooler line. I let the oil pan and the oil cooler line drain overnight with the cover cracked on the oil filter.

The amount of oil that drained from the cooler line was over 1 pint! The inside of the oil filter housing was perfectly dry, unlike previous oil changes.

After filling with 7.5 quarts and running the engine, the oil remains perfectly clean, unlike the past when it became immediately black from the residual oil in the cooler and the lines.

Just a word to the wise.....................