The speaker addresses a little electric pump as if it were a pet or a helper, and gives it a few gentle instructions. The odd, affectionate tone is what makes the poem work. A machine is spoken to the way you might talk to something you rely on and feel fond of.
The key request comes in the middle: "To sense / and sound / this world." The pump is asked to feel and voice the world, which is a surprisingly big job for such a humble object. Yet the advice is practical. Check your "snifter valve," take in oil, and "hum." The poem seems to suggest that understanding the world doesn't need grand effort, just steady, simple working. The word "hum" also sounds like contentment.
The mood is quiet, playful, and tender. The short lines keep everything light and small, matching the size of the pump itself, while the sound of the words (snifter, hum) adds a touch of humor and warmth.