I think maybe I have heard somewhere of greasing muffler bearing on a bright powerbuilt 12.5 rig.
May have been a You tube video???????????
I suspect the OP may be just playing with Us.
Nope not playing. This mower has cranked no problem for probably 15 years. After sitting all winter. This year fires it up, would only run on full choke. Cleaned carb and it ran but not right. Purchased new car, installed and crap loud. Bought new muffler, no change. I messed around with mixture screw and got it to run smooth but still loud. I used brake cleaner (not starting fluid) to spray around to see if I had a gasket leak around intake. By mistake some got in air inlet. It choked down, thought it should rev up. Tryed just barely letting some in and it still chokes.
As for complaints, none. But cutting around baby's nap time is problematic. And when she starts complaining...well you know.