Re: Break in secrets
WD 40 uses propane for a propellant. Be careful when spraying it into an assembled motor. I sprayrd some once in an old chainsaw that had not run in years, and when I pulled the rope to suck it into the motor it fired up unexpectedly and ran WOT for a couple of seconds.
There's no way that WD 40 will hurt a motor by spraying inside of it. I've used prolly gallens of it in the last 40 years. It has never gumed up anything i've used it on.
It does dry up quickly though. Guns sprayed with might start getting corrosion sooner than with light oil.
NAPA sells a light oil aerosol that hangs around a lot longer than WD 40.
The story I got on it's orign was that the millitary was trying to develop a good wing de-icer fluid. On their 40th try of different formulas, one of the scientist realised that this #40 formula was a good penetrating oil.
So the WD might be for "Wing Deicer" rather than the other story about "Water Displacement"
Ask any locksmith, any oil will gum up tumbler locks, for oil collects and holds dust and drebris. The proper lube for locks is graphite powder.