I don't have a specific 041 manual. Have seen them on ebay.
May be you can find an illustrated parts list to help you out if not a manual. Try a search here you might find the info you need. I remember some discussions here on the 041 oilers some time ago.
There is an 041 with out the AV labled Farm Boss and then there is an 041 AV Farm Boss also. I am pretty sure they all use the same oiler parts in all 041's. A majority of the parts interchange between AV and non AV but quite a few differences. I wouldn't put much $ in an non AV to use, the vibration is to uncomfortable for me. I like the 041 AV though. Keep the screws tight they are a fine mid weight work horse for fire wood.