On Dec 7, 2025, Ed Hollingsworth in Omaha, NE, USA wrote:
The doors on the MGA are really light by modern standards. First, there is essentially no machinery inside, not even window regulators or door locks. Second, they are skinned with aluminum, which saves a few pounds. The door hinges have a pretty simple job, so they are dirt simple--just a pair of flattish leaves with fingers and a pin to hold them together. They also incorporate a built-in stop feature to limit how far they will open.

My hinges seemed to be OK in outward appearance. I noticed they were of two types. One pair had number markings on them that identified them as factory parts. The other pair had no such markings, telling me that they were probably aftermarket replacements. I wish I had marked their locations on the car when I removed them, but I didn't. My theory is that the factory pair came from the passenger side, where they got much less use, while the driver's side had the replacements.


In evaluating the parts, I found that the factory parts were still in reasonable condition, with smooth action, and only minor play between the leaves. The aftermarket hinges were much looser, with more play. I also noticed that some of the hinges appeared to have a slight bend in one of the leaves. I reckon this was done when aligning the doors at some point, and since the door gaps were pretty good when I removed the doors, I'm not going to "fix" those bends.

I took the hinges apart, and measured the pins. The pins in the aftermarket hinges showed obvious wear areas that were a full 0.005" smaller than the unworn areas. The bores were likely worn also.


I decided to try to renew the replacement hinges. My first plan was to enlarge the bores to accept new bushings to bring them back to standard 1/4" ID. I bought come sintered iron bushes and some 1/4" precision stainless steel rod for the pins.


As I thought about it more, I wasn't sure how I would get the bushing into the center knuckle. I was also concerned that the 5/16" OD of the bushings would be pretty close to the edge of the knuckles. I think I could have made it work, but in the end, I decided to just use oversized pins.

Possibly someone somewhere makes oversized pins for MGA hinges, but I didn't find them. I did a wider search. The pins needed to be larger than the original 1/4", but not too much larger, because of the limited size of the knuckles. I finally read that pins for old Ford pickup trucks might work. I ordered some. They are stainless steel. These pins measured between 0.277" and 0.278"--just big enough to remove any wear in the bores.

I put an old pin in the bore, and added some spacers between the leaves to make them parallel, then tack welded the leaves together. This was ensure that the bores stayed aligned when the pin was removed. Then, after aligning the bore in the vice, drilled and reamed the bore with a 0.2785" reamer. This made a nice fit for the new pin.


After freeing up the leaves again, the hinge moved freely, with no detectable play. There were a few more things to do though. The new pins had a much too aggressive knurl under their heads, and the heads were way too big. They were also about 1/2" too long. All of that got fixed. Tested to make sure the knurl would go in the bore, then brought the other hinge to the same state.


Took everything apart and blasted all of the leaves. As an afterthought, I hunted down the nut plates that go in the A pillar. Powder coated everything.


Everything put together. The factory hinges are good, but the redone ones are better. I'm considering doing the factory ones, too.

This was sort of a "fill in" project while waiting for parts, but it needed to be done. Cost was only a few dollars for the pins.