Sounds like the lock is worn and releasing to the safety catch. When you get it out, check the areas marked by the arrows on the attached. The lever shown with the red arrow should have a sharp corner on it where it contacts the latch cam, and the latch cam (yellow arrow) should have noticeable serrations along it. That's what keeps the latch cam from rotating and releasing. I think that if you lock the door with the inside handle that also prevents the latch cam from releasing.
I forgot about having to remove the window run channel as well.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
