Door lock mechanism woes

During the past winter I replaced the door lock barrels from ‘t Kreng. This was done to create a matching lock set for the ’76 restoration project. Fast forward to the first drive of the year, and a problem reared its head. Opening the driver’s door from the outside went as usual. But it was when I stopped to take a few pictures, that I noticed something wasn’t as it should. The driver’s door wouldn’t open in the normal way (pull the inside handle and push the door open with the elbow). It actually needed a fair amount of force to open. First thoughts were that something had come loose or that l had refitted some of the parts in the wrong way.

Today I had some time for a closer look into the problem. But after the removal of the door card I could only conclude that nothing had fallen of, had come loose or had been fitted incorrectly. Time for a closer inspection of the movement and action of the mechanism. Using the outside handle showed that everything was functioning as it should. But when the inner door handle was pulled, it was clear that the mechanism wouldn’t fully release the latch.

When pulling the inner door handle the arrowed lever (B) should push the circled lever (A) down. To fully release the latch, the top of lever A should be completely pushed down and hidden from view. But with the inner handle pulled against its stop, half of the lever was still visible. What became clear though was the fact that there was a large amount of free travel when the inner handle was pulled. Only at the last part of the handle's movement would lever B start to push the lever A down. Looking closely at the action of the various parts of the mechanism showed that there was a lot of play in the various parts of the mechanism. But also the connecting rod (arrowed C below) from the latch mechanism proved to have a huge amount of play.

All this added up, and was enough not to release the lock from the inside. As I didn’t want to go to the shed I decided on a little experiment, shortening the pull rod. So I cut of the bent part and put a new hook on. Looked promising but even this minimal shortening proved to be too much. With the handles escutcheon fitted the door would open at the lightest touch. Not good! So I still had to make the trip to the shed, to find another pull rod and a better lock and latch mechanism. Luckily I knew exactly where these parts were stored, so within 45 minutes I was back home.

Swapping the “new” mechanism was straight forward, as per the book! Though I did use the opportunity to remove the old plastic spire nuts that hold the door handle in place, and replaced them with new ones. Always nice to have these small parts in stock! And while I was at it I thought it a good idea to also put new connectors on the door lights wiring. That didn’t solve the light from not working though! But at least I again have a fully functional door locking mechanism.

And that left me with the final job for the day, refitting the door card and the various trim parts. I have to admit that with the work finished, the interior looked most inviting for a quick blast through the country!