In 1925 Castle nuts (without the use of Cotter pins) were still used to fasten the engine block to the pan, but how about the hogshead? Were castle nuts used in the same fashion on the hogshead as well. I know that the fourth main upper bolts used castle nuts with cotter pins and the bottom two were safety wired, it's along the sides that I'm asking about. Thanks
All nuts were the same connecting the pan with both the engine and the hogshead. Lock washers were used instead of cotter pins from december 1924, and some of the screws were slightly longer due to the reinforcement bracket in the corner where the engine and hogshead meet.
Many photos in the 1924 Ford Service show hex nuts on the engine to pan and hogshead cover, the steps note to place lock washers.
Some were perhaps castle nuts with lock washers and some hex nuts with lock washers.
At least by 1924 no cotter pins used on these as lock washers were deemed effective for these fasteners.
Hex nuts with lock washers
# 15 million seems to in 1927 to retain castle nuts and cotter pin on the far right bolt!
Must have been known by those last assemblers that Mr. Ford wanted #15mil to be his way!
Cotter pins everywhere