Long read but, worth it.
Preparing the door
Install the door hinges on the door and make sure that the lower hinge is in the closed position; this will give you a straight shot at it on installation.
Install the door latch; having the door latch installed will help with aligning the door, especially if you’ve taken on the job alone and then, install the door jamb sticker plate.
Prepare the door jambs and gap gauges
Before I mount the door I prep the rear door jambs and rocker panel with my panel gap gauge made out of pop-sickle sticks (you can use paint sticks), this will set the initial gap as well as help protect the jambs and rocker from an impact with the door edges.
Mounting and Aligning the Door
Once the door is mounted and the striker plate is adjusted so the rear of the door is aligned pretty well I move to fine tuning the door alignment.
Door Hinges 101
The body side of the hinges allow adjustments to be made: up, down and front to back.
The door side if the hinge allows adjustments to be made: up, down, inboard and outboard.
Each adjustment should be made to one hinge side at a time, tighten the bolts and then move to the next adjustment.
Problem and Solution
P: The gap between the top rear of the door and the quarter panel is too close; you need to widen the gap.
S: Make the adjustment at the top body side hinge; nudge it forward until you achieve the appropriate gap.
P: The bottom rear of the door is sticking out and is not flush with the body.
S: Make the adjustment at the top door side hinge; pull the top front of the door outward and you will see the lower rear of the door drift inward.
Top rear in or out = lower door side hinge
Bottom rear in or out = upper door side hinge
Setting gap and angle = body side hinges, up down, forward or back
Alignment of Specific Parts
We’re only going to focus on a few parts in this section because there are only a few panels that are considered bolt-on, while the rest are structural or welded-on parts. We’re going to look at the hood, deck lid, fender and door. We won’t concern ourselves with the bumper assemblies, grilles, headlamps or other miscellaneous parts.
Door
The door can be difficult, so pay attention! Doors have always been a challenge and require more analytical thinking than other parts. Today’s automatic door glass drop-downs, airbags, electronic latches and locks don’t make them any easier, either. The principal still remains the same, though: the door or doors must be aligned to the closest welded-on parts first (quarters and rockers) before aligning to the bolted-on parts (fenders and other doors).
Think about it! If you’re replacing both same side doors on a four-door hard top, you’ll install and fit the rear door first because the rear door is bound by the quarter panel/dogleg and the rocker panel. Both of these parts are welded on and provide no adjustment, so you’ll fit the rear door to the quarter/rocker opening and then fit the front door to the rear door and adjust the fender to the front door if necessary. That’s the baseline principal, and usually experienced technicians, given all the weight in the doors, like to load their doors before final paint to assure themselves that everything fits properly – which means the latches are hitting the strikers in the middle and the glass is contacting the weather-stripping without slamming or spring-back and popping. The cheapest place to address issues is in front of the paint booth doors.
Can you run out of adjustments when fitting a door? Sure. What do you do then, bend something? You have to, because something bent it out of alignment to begin with. How you do it will determine how much damage you do or don’t do in the process.
If your door is sagging at the rear and dragging on the striker, verify that the hinges aren’t worn out before bending anything. Open the door and lift on the rear of it. If there’s noticeable movement vertically, you may need bushings, hinge pins or new hinges. If new hinges aren’t available, there may be rebuild kits available from the aftermarket.
If the hinges are good but the door won’t take an alignment with the available adjustments … something has to give. In this case, the door is dragging on the striker, so it needs to come up at the back. Loosen the top hinge on the body side slightly. You don’t want to loosen the hinge bolts more than just a half turn on the upper A-pillar. With a jack, a block and some towels, with the door half open, carefully lift the back of the door with a floor jack. Lift the back of the door with pressure on the door frame, not the door edge/flange. Use caution. With the pressure on, use a bar and a 3-lb. hammer and strike the top hinge firmly and squarely forward to slip the hinge.
Repeat the process of striking the upper hinge with the bar and hammer. Release the jack and check the latch-to-striker alignment. There should be no dragging either on the top or bottom of the latch opening. If it closes properly, you’re done after tightening your bolts.
If the door still sags and you’ve determined adjustment in both hinges is maxed out…it’s time to take your actions up a notch. There are several ways to do this, but I’ll discuss two of the least destructive.
The device that looks like a couple of sockets on the opposing ends of a piece of wire is used between the hinge halves and with the door closed on it to bend or “spring” a door into alignment laterally. Go easy! A little bit makes a big difference, a lot is too much and it’s harder to go back. Check the latch-to-striker position now. It’s good, great! Go to the bank and pick up your money.
Another way to do this involves other devices where the door latch closes over the tool and the jamb is used as a fulcrum to lever the door up or down as needed. Use caution and watch the paint where the fender and door intersect at the top.