Do we need to run some kind of service on reefer engine like valve lash adjustment or injectors cleaning?
I have an old '99 Ultima 53. Never been opened up, lol. Still runs like a top. Same with my '09 2100a.
Nope. We run the hell out of them until they burn up or fail. The reliability reaches decades of operation in some cases. But oil, battery etc are routine. Then either THermoking or carrier onsite or service on call fixes it asap.