Warning: That old mechanic's tip about using WD-40 on actuator linkages

A retired Delta guy named Frank told me to spray WD-40 on the landing gear actuator linkages to 'keep 'em moving.' Big mistake. Two weeks later, I had a 737 with a stuck downlock sensor because the residue gummed everything up in the cold. Has anyone else run into bad advice from the older generation that just doesn't apply to modern hardware?

2 comments

2 Comments

jamief678d ago

Hey come on, is it really that big of a deal? @drew_hart4 I've seen guys use WD-40 on all kinds of stuff for years without any major problems, and most of the time a little cleanup fixes it right up. Unless you're soaking the whole thing down like a fire hose, a quick spray isn't gonna wreck a sensor that fast.

drew_hart48d ago

That Frank guy probably meant well but he's stuck in the 1980s. Had a similar mess with a CRJ after following some old timer's advice about cleaning pitot-static ports with contact cleaner. Guess what, the seals swelled up and we got false airspeed readings. The real issue is these older mechanics don't get that modern sensors and actuators have tight tolerances and plastic parts that can't handle solvents. WD-40 is basically a petroleum-based goo that collects dirt and freezes. Good rule of thumb now is to just use the approved silicone grease from the manual and nothing else.