SuperHart B&G has a engine flush system that washes out all the
oil in the motor and cooler lines. Dealerships have them. They work but I don't believe in washing a motor down with something that looks and smells like kerosene. The best way is to remove the lines and cooler and let the drain by hanging up. Run some brake kleen through the lines and cooler and let drain. Blow this out with LOW PRESSURE AIR. 20-40 psi. Reassemble and fill the system with new
oil. I wouldn't worry about this UNLESS you have had a motor blowup and have metal in the
oil pan. Add a magnetic half cup to the oil filter. This will catch alot of any metal particles. I would leave the rest alone. You have learn the line of letting sleeping dogs lay.
Rick Lake