5-43. CYLINDER BLOCK-MAINTENANCE INSTRUCTIONS (Continued).
The tapped holes in the cylinder blocks may be tapped with a 5/8 inch-11 UNC3B
thread tap. The stud holes and unplugged bolt holes must have the thread
extending 1.84 inches below the block surface.
m. Check the remaining cylinder block surfaces and threaded holes. Check all of the
mating surfaces, or mounting pads, for flatness, nicks andburrs. Clean-up
damaged threads in tapped holes with a tap or install helical thread inserts if
n. After inspection, if the cylinder block is not to be used immediately, spray the
machined surfaces with engine oil. If the block is to be stored for an extended
period of time, spray or dip it in a polar-type rust preventive such as Valvoline Oil
Company's "Tectyl 502-C", or equivalent. Castings free of grease or oil will rust
when exposed to the atmosphere.
Before a reconditioned or new service replacement cylinder block is used, steam
clean it to remove the rust preventive and blow out the oil galleries with