Removing the Door Frame
Remove the trim from inside the door. Undo the four domed nuts securing the door latch, then remove the two check strap screws. The inner door trim can now be removed by unscrewing the fixings around the perimeter. Prise out the tacks securing the arm rest padding and remove it from the top of the door. Remove the trim located forward of the door in the footwell. The six bolts securing the door hinges will now be exposed. Undo them and remove the door frame. Carefully examine the frame and if it shows any signs of rot, the door skin will have to be removed.
Repairing the Door Frame
The trick with making door parts is to make them slightly thicker than the original. Replicate the joints as accurately as possible. When you have made the new parts, re-assemble the door frame using small clamps. DO NOT glue or screw it together at this stage. Make up some 25 x 25 x 8mm thick packing pieces and place them between the door and body frame, as illustrated in Figure 2. Two 25mm strips of 4mm plywood glued together and cut into small lengths are ideal for the purpose. Do not put packing pieces between the hinge stile and hinge post. The hinge rebates can be checked by bolting the hinges to the hinge post and ensuring they align with the rebates on the door stile. At this stage the door frame may have to be shaved down to fit. If the slam is not correct, use thin wedges in the joints to obtain a perfect fit. These will indicate how to trim the joints.
When you are satisfied that the door frame fits the aperture properly and the joints are tight, remove the wedges and use a good quality urea-formaldehyde glue and stainless steel screws to finally assemble it. Allow 24 hours for the glue to set before disturbing it. When the glue has cured, fit the hinges, replace the door skin and hang the door.
Antiburst Door Latch
Land Rover door latches were fitted to 1970's Morgans. They still appear on the internet advertised as brand new and priced around thirty pounds. They are burst proof, latches, which are easy to fit and adjust. When closed, the door latch cam wraps itself around a strong peg on the striker plate, which prevents lateral movement in a side impact. If the door buckles on impact it would automatically shorten, imparting a stress which could pull the latch cam off the peg. This is prevented by a flange on the end of the peg.
When the door handle is lifted, the latch cam rotates and lifts clear of the latch peg on the striker plate, enabling the door to be opened. If the door is closed very gently the latch cam will engage with the latch peg and rotate to 'Latch position 1', as illustrated in Figure 3 and the door will appear closed. If the car is driven off, the door will rattle, although it will not come open.
Close examination of 'Latch position 1' shows the top striker guide on the door latch not properly engaged with the rubber mounted one on the striker plate. The latch cam is not fully engaged with the peg either. This is why the door rattles. The door can be pulled harder, or opened and slammed to make it take up 'Latch position 2'. This ensures the door is closed properly.
The door has two locking positions for safety reasons. If the lock fails in the fully locked position, it will fall back to 'latch position 1' and still remain locked.
Adjusting the Striker plate
The illustration of the 'Antiburst door latch' in Figure 3 shows a bent plate surrounding the latch cam. This guides the door latch into the striker plate. The striker plate also has guide plates which engage with those of the latch, ensuring alignment when the door is closed. The lower guide on the striker plate is rigid, whilst the one on the top is mounted on a rubber buffer. These locks were originally intended to fit Land Rovers, which have rubber door seals. The rubber buffer accommodates for wear and compression of the door seals. Morgans do not have rubber door seals, so careful adjustment of the striker plate is necessary.
The striker plate is mounted on a steel bracket that helps support the latch post, as shown in Figure 4. Adjustment is achieved by slacking off the two bolts that fix the striker plate to the mounting bracket. The striker is then moved in or out to achieve the correct position. When the door is fully closed it should not rattle, but avoid an over tight door adjustment, which will cause the door to rub against the quarter panel and damage the paintwork. A thin rubber pad fixed to the inner rear of the door may help to give a tight and rattle free shut.
Removing the Door Latch and Striker Plate
Removing the door latch is straightforward. From inside the car, remove the screw and cup fastenings securing the door trim and check strap. Remove the four dome nuts and washers securing the latch and remove the door trim. Lift the latch off the securing bolts.
To remove or adjust the striker plate, remove the screw and cup fastenings securing the quarter panel trim and remove it. Access to the nuts securing the striker plate is gained behind the steel support bracket.