I have a 800 hp 19C that has lost about 10 gallons of oil since the start of the season. I checked it today and found that when the vanes are under 25% open that I'm getting more oil foaming than normal. I didn't do the winter shut down on it this year, but a friend of mine did. Oil pressure was a little high at 28 psi total and the oil cooler had too much flow. Bearings wear below 140 degrees. I brought the bearing temp up to 155 and reduced the oil pressure a couple of pounds. I told the customer to keep a close eye on it. Everything else on this machine looks like it has for years.