GM Seatbelts-1979 Caprice FYI

So i had been wondering if my seatbelts were too old and broken in my 79 caprice 2 door, because they wouldnt lockup when id yank the belt fast because ive been in many cars where this type of test would work. So i decided to take the passenger side seat belt apart to see whats going on. Turns out they work just fine, they operate with a pendulum. A lead weight hangs down below the lock plate, when the weight moves in any way, it pushes the lock plate up. The only way it will lock up is if the car hit something or slowed down abruptly, so one day im going to go out and test it. I had been searching to find new seatbelts to install, simply because i thought mine didnt work. I also tested the inertia front seats(this applies to the 2 doors only) and they also work. If you read the owners manual it clearly says there is no way to test the inertia lockup, but you can just push the seat up fast and they should lockup, im not sure how they work because i dont know how to take it apart lol. Lastly I tested the back seat seatbelts, and those work fine, they automatically lockup once they are pulled out far enough. Also the front seatbelts have a "comfort adjuster" youll see in the pics below a black lever in the door jamb, once the door closes it allows this mechanism to lock so once you get the seatbelt on, you can pull the belt out an inch or two so it wont choke you, but I always prefer a snug seatbelt. I learned alot of stuff today regarding seatbelts, i also found this cool article on HowStuffWorks explaining the two different types of seatbelts, our type is the first one. Heres the link to that to see a diagram: http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/seatbelt3.htm


Heres the lockplate disengaged:

And with the lockplate engaged:

The intertia locking front seat mechanism, also if you look close enough, youll see a pill on the floor, i found a Midol pms pill under the backseat lol oh and a mcd monopoly game piece from 1989

Just thought id update, so i went out today and tested my belts like i said, i braked hard and pulled the belt and it locked up, i feel somewhat safer now lol

I've often wondered how good this pendulum action works. They are awful on the Firebirds which have the same sort of pendulum action except the retractor is in the roof of the car and it doesn't have the door engage at all. I watched the crash test video on youtube for the same body Firebird and Camaro and the seatbelt doesn't lock the dummy to the seat, it lets the dummy smash his head into the steering wheel as the dash and steering wheel are rising upward. Sucks to watch. Hope I NEVER crash one head on.

@ solo79 Ha ha ha, that got me rolling man.