Throttle shaft lubrication

[lesterthedog@go.com]

Is there any way to lubricate the throttle shaft that runs through the motor housing on my 40 Yamaha? There is a small hole in the top of the shaft housing that is full of a thick grease-like material. Does this hole open into the shaft for lubrication? Is there a special lubricant I can use? Any help would be appreciated. Thank you.