Diesel cement mixer electric start +

Commodore Baromix cement mixer We have owned this mixer from new and it has been regularly serviced. It has only been used by us and never hired out so there have been times where it has sat unused for months. There is some cement and concrete on the frame and in the tub but it will clean up ok. It starts and runs as it should but has sat for 18months so could do with a service. This is a 2004 machine and has this date along with the serial number on the sticker but it hasnt shown in the photo.