I'm doing a playthrough of Far, and this is my second playthrough. It starts after the engine module is installed, which is when you can douse the engine to keep it cool.
- Install the engine module.
- Put trash on the wires that feed into the gasoline tank.
- Press the button on the roof on the middle floor (to the left of the air bag/pump). It will load the tank.
- Press the button above the air bag/pump, and pump air into the fire, increasing the size.
- When the fire gauge gets into the blue, the tank will start heating up on the right side, indicated by a raising orange bar.
- Grab the hose, set the output to water, and douse the engine.
- If you leave it too long, the top will pop out and stop the boat. This can also be cooled down for the achievement.