Treasurer Scott Morrison says it's not up to Liberal members of parliament to lecture the grassroots on how to conduct party affairs.
About 1500 Liberal members will gather at a special convention in Sydney this weekend to debate changes to the way candidates are selected and other measures to boost member participation.
Mr Morrison, a former NSW Liberal state director, said he was in favour of "democratisation" in the party.
But any specific rule changes were a matter for party members and not something he would publicly advocate.
"I don't believe it's my job as a parliamentary member of the Liberal Party to be going around lecturing the organisational wing about how it should conduct its affairs," he told reporters in Melbourne on Thursday.
"I'm a fierce defender of the organisational wing of the Liberal Party to make decisions on the issues that are within its domain."
Two federal Liberal MPs, Alex Hawke and Julian Leeser, are crunching the numbers on a series of motions which would head off a push led by former leader Tony Abbott for a deeper overhaul of preselection rules.
Prime Minister Malcolm Turnbull will address the convention on Saturday.
