Mr Wilson's motion called for the release of details of employment or profession, land interest, any company, trust or partnership and those of an elected member's partners.
But councillors Dave Macpherson and Gordon Chesterman said the motion did not go far enough.
Mr Macpherson said the council should decide collectively to make it mandatory rather than voluntary - until the new Local Authorities Members Interests Act was finalised. Under this act local government public registrars of elected members' financial interests are expected to be mandatory.
Deputy Mayor Gordon Chesterman said it needed to include superannuation, cars, membership of political parties and community organisations.
Mr Chesterman said his own retirement fund was tied up in commercial property but questioned why superannuation should not be exposed as they both had the same end result.
"This is tragic, this is not becoming a debate about conflict of interest but a wealth register," Mr Chesterman said.
Mr Wilson criticised Mr Chesterman for voting for a rate reform when he stood to benefit because he owned a number of commercial properties in the CBD. Under the reform, commercial property was to benefit from lower rates.
But Mr Chesterman turned the tables on Mr Wilson and said his previous fraud conviction also needed to be recorded.
Councillors Maria Westphal and Pippa Mahood criticised the way the motion was sprung on them and Mr Wilson was also accused of pulling a "publicity stunt".
Mayor Julie Hardaker said the working governance group would continue to look at conflicts of interest if the law did not address them first.
The council voted five for and eight against the motion.
VOTING RESULTS
For
Councillor Ewan Wilson's notice of motion
Daphne Bell, Martin Gallagher, Angela O'Leary, Ewan Wilson, Roger Hennebry.
Against
Julie Hardaker, Gordon Chesterman, Margaret Forsyth, John Gower, Pippa Mahood, Maria Westphal, Peter Bos, Dave Macpherson.
