Emerald and anyone else that may be able to help,
  I have been trying to locate maintenance schedules for some obsolete Lister engines for a friend of mine.  He is using them on his farm as standby generators and would like to follow a routine maintenance schedule to make sure they are ready to perform when needed.  They run intermittently, sometimes for a couple of days, but mostly they run for short periods during power outages.  I  don't know the serial numbers yet but he tells me that they are the following models,  HA3, HR3, SR3 and TS3.  I think he got them from a government surplus sale. 
  They are working OK but he hasn't really done any maintenance other than checking the oil every so often.  He is concerned that there may be some issues with these engines that require special attention so he wants to set up a schedule of regular maintenance.

I have been able to find the operators manual for the TS3 which has a routine maintenance section, but have had no luck with the others.  All he needs is a basic recommended maintenance schedules which would probably be located in the owners manual.  Unfortunately he is not "Computerized" and does not have connectivity to the internet.  So being the nice guy I am, I volunteered to check it out for him.  Little did I know at the time that it would be so difficult to find info on these long serving engines. 

Do you have access to these manuals and if not, do you know where they might be available.

Any help would be greatly appreciated.

Cheers,

Hooty