Additional thoughts, from over a decade of running Optis– 1. They need to warm up to at least 123 degrees before you run them. 2. Agree with coming off pad, and idling for a minute or so before you shut them down. 3. ESPECIALLY in cold weather, crank them and let them warm up, before you initiate a hole shot. PUT IN A TEMP GAUGE IF YOU DONT HAVE ONE! The other thing an Optimax will do, because of the lower unit torpedo pickups, is ingest small pieces of wood, especially in the spring, when junk is floating everywhere, and it will wind up in the thermostat, and stick it open. When that happens, youll never see 100 degrees of temp. Ive seen it below 90. Long term, this is not good. I keep one of the windows on my SmartCraft gauge set to display temps at all times. It can save you a powerhead. Mike Whitten/Germantown, TN