At his time of death, he had been due to start recording the 25th series of Last of the Summer Wine.

He was born in Manchester, Lancashire, in 1933, and served in the Royal Air Force during his national Service. Wharmby was originally employed as a Painter and decorator and had no formal training as an actor. He gained stage experience with Oldham Repertory Theatre and worked part-time as a jobbing actor. Early television roles included bit-parts in programmes such as Bill Brand (1976), The One and Only Phyllis Dixey (1978), and Coronation Street (1982).

He was then auditioned for a one-line part in Last of the Summer Wine, which had begun in 1973, filmed in and around the Yorkshire town of Holmfirth. The Producer, Alan J.W. Bell, was so impressed with Wharmby's "natural" performance that, instead, he cast him in the more prominent role of the bumbling Wesley Pegden for another episode and Clarke later wrote him in as a regular. Although initially overawed by working with Thora Hird as his screen wife from 1986, Wharmby eventually started giving her "notes", to the veteran actress's great amusement.

Wharmby made his debut in Last of the Summer Wine in 1982, as Wesley Pegden, the boilersuit wearing, tinkering mechanic and would be Inventor. He appeared as a regular cast member for 16 series between 1985 and 2002. Thora Hird played his nagging wife Edie.

Wharmby had small roles in programmes such as Troy Kennedy Martin's nuclear thriller Edge of Darkness (1985), Brookside (1985), All Creatures Great and Small (1988), A Very British Coup (1988), Agatha Christie's Poirot (1990), Heartbeat (1994), and Hetty Wainthropp Investigates (1996).