When I run my JD LT155 after sitting I get some thick milky oil on my dipstick. I assume it’s condensation from sitting. The oil is new and so is the filter. How long should I run the engine to help burn this off? Should I leave the oil cap off during this process? Thanks. I’m running Valvoline High Mileage Full Synthetic 10w30 with an Ecogard s241 (51348 size) filter.