Originally Posted by Randy
In the Camguard webinar it was stated that one of the biggest mistakes made by Lycoming was in changing their recommended oil change interval from 25 to 50 hours when they started using filters instead of screens. It was also stated that most of the beneficial additives in the oil that help prevent corrosion are evaporated away by about 25 hours of operation...
Filters do not take out the acids or water from the oil.
That was one of the main points I took away from the Camguard webinar, 25 hours is about maximum interval, and additives can be replenished when you add a quart of oil. Some Camguard can be added each time oil is added.
My practice on my personal plane(s) is to change the oil every 25 hours and the filter every other oil change. Oil is cheap (relatively). Engines are expensive. This is what I recommend to my customers as well. I use Phillips X/C 20W-50 with CamGuard. I usually take a couple of extra quarts from the case and open hem up and add about 1.6oz of CamGuard to each quart and write a “C” on the cap to show it has CG in it and I recommend to use those when adding oil to keep the recommended amount of CG in the oil.