Definition
A proprietary chemical conversion process in which steel parts are immersed in a manganese phosphate solution to produce a thin, non-metallic phosphate coating on the surface. This coating holds lubricating oil in its pores, reduces friction, and prevents galling and seizing during the break-in period of close-fitting moving parts such as piston rings, cylinder walls, gears, and tappets.
Plain English
A factory treatment that gives steel parts a slightly rough, oil-holding surface so they slide against each other smoothly when first put into service, without scraping or sticking.
Context Anchor
Seen in aircraft maintenance manuals, overhaul instructions, and parts specifications for treated steel components.
Derivation
Parco is a trade name from the Parker Rust-Proof Company, which developed the process. Lubrizing combines lubri- (from lubricate, Latin lubricus, meaning slippery) with -izing (to treat or convert). The name signals that the surface itself is being converted into something that helps lubrication.
Why Pilots Care
Pilots and owners reading overhaul records or parts specs may see this term and need to recognize it as a standard surface treatment, not a defect or coating that should be cleaned off.
Intuition Check
Do not read “Lubrizing” as just applying oil. Here it means chemically treating the metal surface so it can hold oil and protect itself better.
Example Sentence 1
The piston pins were Parco Lubrized at the factory to reduce wear during the engine's break-in hours.
Example Sentence 2
Fasteners treated with Parco Lubrizing held up better against moisture during long-term storage.