He was employed as a scout by Birmingham City, but acted as caretaker manager on two occasions. The first time was for three games between the departure of Dave Mackay and the arrival of Lou Macari in early 1991; Birmingham remained unbeaten under his management. After Macari walked out in June 1991 to join Stoke City, Coldwell again took over as caretaker, this time persuading a significant number of out-of-contract players to re-sign (and not leave the club with Macari), and supervising pre-season training until the appointment of Terry Cooper in August 1991.
In April 1993 he replaced Len Ashurst as manager of Southern League Weymouth. Unable to prevent relegation to the Southern Division, he stabilised the club and achieved a mid-table finish with a young side in the 1992–93 season, but was sacked in September 1993.
- Clarkson, Ian (27 July 2007). "Former Blues' star Clarky recalls the pain of pre-season training". Retrieved 7 November 2010.
- "First-Class Matches played by William Coldwell (2)". CricketArchive. Retrieved 29 November 2007.
- "William Coldwell". Cricinfo. Retrieved 29 November 2007.
- "Managers". BCFC Archive. Tony Jordan. Archived from the original on 26 March 2003.
- Matthews, Tony (1995). Birmingham City: A Complete Record. Derby: Breedon Books. p. 48. ISBN 978-1-85983-010-9.
- Biddlecombe, Nigel (3 May 2006). "Too long in the wilderness". Weymouth F.C. Retrieved 29 November 2007.
|This biographical article related to an English association football manager is a stub. You can help Wikipedia by expanding it.|