After I got home, I popped the back open and removed the film, and then let the back drop closed. As it shut, I heard something small click and clatter on the floor, and the door wouldn't latch. A quick look showed that tip of the little hook had sheared off the sprung latch on the body when the door had swung shut on it.
The N4004 was Nikon's entry-level SLR back in the late '80s and made extensive use of plastic parts; apparently the film door latch breaking was a not-unheard-of malady. Once upon a time, you could have sent the camera back to Nikon to be repaired. Now, in the era of digital photography and twenty years after the N4004 had been discontinued, and when excellent condition N4004 bodies are $19 from KEH, it'd hardly be worth the shipping to see if it could be fixed.
Bummer.
I'll set it aside on a shelf for a rainy day project and move the lens over to my backup N6006 body, I guess.
