I tune up and repair small engine equipment as a hobby and source of extra revenue for neighbors, friends, and their referrals.
The other day I picked up a 7.25 HP lawnmower with a Briggs and Stratton motor that was completely locked up due to running out of oil.
I added B-12 to the Crank Case, and slowly turned the blade after letting the solvent work for 6 hours.
After finally freeing the blade completely around, I was able to start and run the mower with ONLY B-12 in the crank case.
I thought it was a gonner, but B-12 did the job!