Bulkhead Corrosion
Most of the control components and the central core of the wiring loom are mounted on the bulkhead. It forms a major part of the car and its integrity is important, as it protects the occupants legs in the case of an impact. Its removal usually involves stripping most of the front end of the car. This is unfortunate, because in the case of older Morgans the bulkhead is the most rust prone panel in the car. Most of the panel is visible from under the bonnet and usually shows no sign of significant corrosion. However, if the trim is removed from inside the footwell on either side of the car, the true condition will reveal itself. Externally this section of the bulkhead is hidden by the chassis and the inner front wings. If you are purchasing an older Morgan, make sure you can look behind the trim and examine the bulkhead. The rot shown in Figure 1 is typical. In 1986 the bulkhead was powder coated and a galvanised chassis was offered as an optional extra. Nowadays Morgans have stainless bulkheads.
Whilst it may be possible to remove the bulkhead whilst leaving the front wings in place, it would hardly be worthwhile. If the bulkhead is rusty, the inner wings will also be corroded. Unless the bulkhead is extensively corroded, a little practise with a MIG welder should enable you to bring the bulkhead back to excellent condition. Hopefully the method described below should be of some use. Remember to always make templates before cutting old metal away.
Removing the Bulkhead Components
Figure 2
The components and panels which require removal before releasing bulkhead are listed below. Click the links for more information.
Remove the front wings and bonnet
Remove the Inner wings, cowl and cowl box
Disconnect and Withdraw the wiring loom
Remove the steering column
Remove the fuse box
Remove the starter solenoid (Connections shown in Figure 2)
Remove the screenwash bottle and motor
Remove the brake switch and master cylinder
Remove the windscreen wiper motor
Remove the Heater and hoses
Remove the One Shot lubrication valve
Disconnect the throttle and choke cables cables from the carburettor
Unscrew and disconnect the cable from the rear of the speedometer
Disconnect the Alternator lead along with the temperature gauge wire
Undo the 'P' clips and release the fuel line, then withdraw it through the bulkhead
Undo the small bolts just to the offside of the steering column, then remove the throttle pedal from inside the bulkhead.
Release the bolts securing the main loom to the inner upper side of the bulkhead.
Undo the bolts securing the toolbox to the upper bulkhead. (Some cars may have a battery installed alongside the toolbox).
Removing the Bulkhead from the Chassis
Figure 3
When the above components and panels have been removed from the bulkhead, undo the 27 screws that fix it to the scuttle frame, as indicated in Figure 3. Undo the bolts that secure the bulkhead to the chassis. Remove the 4 bolts which secure the bulkhead to the transmission tunnel and finally check that nothing else is bolted to or preventing the bulkhead from being lifted clear. Make a template of the rusty parts of the bulkhead before lifting it clear, because areas of rust will often disintegrate during the lift.
Repairing the Bulkhead
Figure 4
Having made templates of the rusty areas, cut them away. Using the templates, identical steel panels can now be made of the cut away steel. These new panels can be welded flush with the sound clean steel of the bulkhead. When ground and polished, this leaves an almost invisible repair, which should be as strong as the original panel. The only draw back for an inexperienced amateur when making this type of weld on thin steel, is the tendency to risk buckling the panel. Stitch welding or tack welding the join first can help alleviate the problem. See the section titled 'Welding Thin Steel' on the MIG welding page.
The method I used on my own car was to produce swaged edges on the new panel which overlap the old steel of the bulkhead. When cutting out the new panels, I added the margins labeled A and B as illustrated in Figure 4. Joddlers were used to form margin A, whilst a simple 90 degree fold was made along margin B. The new piece of steel was then welded with the flanges overlapping on the inside of the bulkhead. The seams were welded on both sides of the bulk head. Margin C was flush welded. This made really strong double welds on margins A and B. The double welded seams must not have any holes left in them, otherwise water could get in and cause corrosion. The inside seams can be protected with sealant as they will be hidden by trim inside the car. The outside seams are ground flush with an angle grinder. Any imperfections can be lost using body solder. If epoxy body fillers are used, they can eventually crack after years of service. Body solder will remain intact, even when panels flex. However, it is important to remove any excess flux before painting.
Small holes can be filled with weld. If you are not an experienced welder, practise on scrap pieces of steel first. You will be surprised how quickly you can learn to produce good welds with a MIG welder. However, carefully read the instruction manual first and take the correct safety precautions before attempting to use the welding equipment. You can severely damage your eyes if the correct protection is not used.
Reassembly is the reverse of above. When re attaching the bulkhead to the scuttle frame I used stainless button head bolts instead of screws. These can be seen in Figure 2. I feel this gives extra strength to the assembly and makes future maintenance easier. The heads of these bolts are recessed for allen keys, which are so much easier to use than a screw driver.
Restored and fitted Bulkhead
Figure 5
Figure 5A shows the restored bulkhead after painting. The odd looking colours are reflections of nearby objects. I put the high finish on it, because it makes the job of cleaning it so much easier in the future. I also made sure to avoid the mistake that Morgan had made, by painting it after fitting it to the chassis, along with the front inner wings. Looking at the state of the bulkhead in Figure 1 you can imagine why I considered purchasing a new one, particularly as I had never used a welder in my life. However I purchased a MIG welder, which saved me a lot of money in the long run. If you have never welded before, do not be put off trying it for yourself. The bulkhead was the first welding project I had ever attempted. I must admit to practising on old pieces of steel before trying to weld new steel into the bulkhead. If the chassis had needed welding I would have most probably called on the services of a professional welder, but as it happened, the chassis was in good condition and only required cleaning up with wire brushes on an electric drill before re-painting. Nowadays Morgan chassis are powder coated or galvanised.
Figure 5B shows the bulkhead bolted back on the chassis. Note the large washers used. It helps spread the load around the bolt. Stainless steel bolts are expensive, but worthwhile fitting, because they will be easier to remove in the future. Also use a good mastic sealant between the chassis and the bulkhead. Do not use silicon sealant, it is near impossible to paint over and is extremely difficult to remove from surrounding panels.
