another noisy lifter ?

This is a pre magnum 318 hydralic flat tappet cam. The engine hasn't been started for 12-18 months but ran fine before. I just got it going again, has excellent oil pressure but has a noisy lifter or 2. Can i expect the ticking to go away if i keep running it or should i be doing something .
Can the engine be damaged if the ticking continues
Thx for looking