Since you are running the dual-line pressure tank start by closing the cap on the tank. Push the button on the tank until you feel some resistance. Pull out the choke knob on the engine, place the shift lever in Neutral, rotate the throttle handle to Start and start pulling on the recoil. If the indicator on the throttle is not legible then start should be below the middle of the travel and you should not be able to go to full throttle when in neutral. After the motor starts push the choke knob back in and adjust the throttle to idle. Let the motor warm up a couple of minutes before going to full speed. When engaging the shift lever into gear make sure the throttle is below the start position and quickly engage the lever into gear. Don't try to ease the motor into gear as it causes the gears in the lower unit to grind and ruin the shift dog and gear lobes. As for fuel/oil mix since you are using the pressure tank use 1/2 pint of TCW-3 oil per gallon of fuel and if possible avoid the use of Ethanol fuels.
