You mean the gear puzzle? If you're absolutely stuck, you can consider getting my savegames, this could help you. Click this URL:
ftp://ftp.soulianis.com/archive/indy/
You find the teo-gear-puzzle files there (1,2,3, and 4 - one for each step), both zipped (.zip) and original (.nds) - the .zip files are compressed and require WinZip or pkunzip to decode.
I saved these files with the update 1.2 installed. If you don't have it, you should download it from LucasArts first, or my savegame files won't work. The location is:
ftp://ftp.lucasarts.com/patches/pc/J3DUpdate1.2.exe
Download it, then double-click it and it will install itself.