The "official" Google-given method given is this, but it doesn't work. In Terminal
defaults write com.google.Keystone.Agent checkInterval 0
The most foolproof method is to empty these directories:
/Library/Google/GoogleSoftwareUpdate/
~/Library/Google/GoogleSoftwareUpdate/
Then change the permissions on both folders named GoogleSoftwareUpdate
so that there's no owner and no read/write/execute permissions.
In terminal:
cd /Library/Google/
sudo chown nobody:nogroup GoogleSoftwareUpdate
sudo chmod 000 GoogleSoftwareUpdate
cd ~/Library/Google/
sudo chown nobody:nogroup GoogleSoftwareUpdate
sudo chmod 000 GoogleSoftwareUpdate
If you want to be double-certain, then do the same for the folder Google one level up.
cd /Library/
sudo chown nobody:nogroup Google
sudo chmod 000 Google
cd ~/Library/
sudo chown nobody:nogroup Google
sudo chmod 000 Google
I did this immediately after installing the Chrome version I need for my machine, and it worked perfectly. Now when I check About Google Chrome it gives me the error "Update failed (error: 10)"