Guys I have a Starrett indicator that hasn't been used I guess over 30yrs maybe.I got this from the father inlaw after his passing and I dont think he's used it maybe another 10 plus yrs.He used it to align pumps with motors so knowing him it was never abused.The other day while dialing in my vise I think it may have been hanging up little.I would take my finger and using the mushroom pad I would kinda push in on it then let it go back into place.I did this couple times and got different reading up against the jaw of the vise.So knowing how long its been setting up maybe its sticking,is it possible to help this using an oil/lube?Just rubbing a light coat of the shaft of the plunger,is there something else that can be done to help this old tool thats been setting?The pic here is not the indicator but just like the one I have,just help me explain since I don't know the correct terminology.