I’ve been having problems with my seat belt for a couple of months now. It won’t release enough for me to get it around my waist. If I’m on a slight incline it won’t release at all. No amount of gentle tugging, violent pulling, or whispered pleading would help. I decided I’d take advantage of 50˚ weather today to pull the ratchet mechanism apart to see what was wrong.
My seatbelt is based around a simple mechanism involving a single ball bearing in a cup. When the ball is stationary in the cup, the seatbelt has give and will release properly. When the ball is moved out of the cup by a strong force–say, a collision–it contacts a pawl which closes a ratcheting mechanism and stops the belt from releasing. Most of the online sources I found said the mechanism was probably filled with dust and the ball was stuck. I pulled it apart and shook out about a pound of dirt, straw, leaves, and dust, but the mechanism was still jammed. After blowing dust out of the cup with a can of compressed air, the mechanism started working and all was well again.