Rant: Lost a bolt in a Cessna 172 engine bay near Oshkosh last summer

I was swapping out a spark plug on a 172 at an FBO outside Oshkosh during AirVenture. The dang 3/8 inch bolt slipped out of my hand and dropped into the cowling somewhere near the exhaust manifold. Took me 45 minutes with a magnet and a borescope to fish it out from behind the oil cooler. Now I always tape a rag over any open gaps before I start a job. Anyone else have a bolt vanish on them in a tight spot like that?

2 comments

2 Comments

lane.joel22h ago

Wait, did you check that the bolt didn't just fall onto the apron instead of into the bay? Everyone always assumes it went down into the engine, but half the time that clatter you hear is it bouncing off the cowling and landing on the concrete. I've seen guys spend an hour fishing around for nothing while the bolt is just sitting under the tire.

the_charlie18h ago

Respectfully disagree with you Joel. In my experience that clatter is usually metal on metal inside the cowling. Bolts don't bounce off fabric bellows and land clean. They wedge themselves in between the engine mount and a hose. And the apron is greasy and dirty. If it was on the ground you'd see it before you even started looking. A clean dropped bolt stands out like a sore thumb on stained concrete. I've come around to the side that if you hear the drop and don't see it on the ground right away, it's down in the bay 9 times out of 10.