A nostalgic look at AMC production
by Tom Benvie
As seen in American Motoring, Volume 13, Number 5, the newsletter of the American
Motors Owners Association. reprinted here with permission of the author. All rights
reserved.
As much as we hate to admit it, AMC is no more. Worse yet, the Kenosha plants have been closed. I believe this is the final blow. No longer can we see how the cars were built, no longer can we witness the brand new AMC automobiles roll off the assembly line for the final check. No longer will we see the rows and rows of cars lined up waiting to be sent to their eventual new homes. For some of us, we had been able to see the cars whenever we were near the plant. I personally saw it a dozen times and never tired of it I saw the first Pacers, the first Pacer wagons, the Spirits and Concords. But never more. For those of you who did not get to see the plant, I'd like to take you on my own tour so you can visualize the process.
To begin with, the plant I am going to describe is an assembly plant. That means all the components and parts are made elsewhere and shipped to AMC. Some were made down the street, others across the country. Ever notice how some parts are the same for AMC, Ford, or Mopar? Usually it just means they buy from the same supplier, not necessarily are they buying a competitor's part. (Are you tired of being told AMC means "A Mongrel Car" because of all the parts from other makes that are on them? Well, try this. Most wheels for all U.S. cars are made by Detroit Wheel. Most glass, by PPG or Coming. Tires, by Firestone, Goodyear, etc. Most brakes, by J. P. Stevens. Etcetera. etcetera, etcetera. ALL makes buy parts from subcontractors, so no one makes their whole car by themselves. In 1971, AMC had 16 plants in North America alone, some making engines, some soft trim, some assembly or foundry plants. But all the parts were shipped to Kenosha or Brampton, Ontario for final assembly. So let's begin with the point that all the parts are in place at the plant.
First we have the subassembly area. Here the parts that make up the floor and firewall are all welded to form a single unit. All AMC cars since the 50's are unit body construction -- there was no separate frame section. Instead, the body was welded to become one unit that acted as the frame. The floor and firewall, the first section assembled, is the base of the car. While this is happening there is action in another area just ahead. The sides of the car are being put together in special jigs or holding tools.
The sides consist of the rear wheelhouse, rocker panel, interior bracing, door jambs and quarter panel. From here it moves to an area where a roof section is welded in place. With this done, it approaches the "Shell Drop" area This is where the upper section is welded to the floor and firewall section. The car you now have is the finished shell. To give you an idea of what this is, imagine you are stripping a car and have removed every single nut, bolt, and part. This is what you would have-a bare shell. The next section is door assembly. As there are no guts, latches or weather stripping, alignment is easy and fast. After the doors are on, the hood and trunk are fitted, along with hinges and related parts. Hood alignment is easy as it must align against the firewall cowl panel only. From here, the fenders, fender caps, and quarter panel end caps are installed. Also, the pedal assembly (by one bolt and two firewall braces) and the front and rear valance panels, if so equipped, are installed. Now the body is inspected. The next step is paint, so it has to be perfect. By this time, a lead filler is used at the four roof joints, all panels are checked for roughness and straightened, and all hinges are checked. If there is a problem, the car is pulled off the line and corrected, or destroyed if it is a severe problem (though it rarely happens). (Now you see how some body numbers on the data plate could be out of sequence). Now the body is completed, and anything that will be painted body color is now on the car. (An exception were the 69 Big Bad bumpers, which were hand sprayed and assembled later.) The car is now picked up by the roof and dipped into a 6-stage chemical bath. These phosphates and "Bonderite" process seals the joints and readies the car for paint. However, before it is dipped, it is submerged up to the top of the doors in an anti-rust solution.
Now the car will receive seven coats of primer and paint. Between the primer and the paint, the cars are hand sanded and an overhead system washes away all residue. The car then goes into a drying oven before the final coat. By this time the car is no longer supported by the roof, but sits on a platform that sets into the various mounting holes in the car's floor. (These are the ones with the plastic plugs in them, under the carpets). Now the car is hand painted, all over. This is not the same way your body shop does it however. The paint particles are "charged" and stick to the car when sprayed. It is also done in a temperature controlled booth to allow for and insure proper drying. In the end, there will be plenty of runs under the hood, trunk, wheelwells, etc. (hurry up areas), but not the outside body. Also, paint usually did not get behind the fenders at the cowl, or under the tops of the fenders or the lower, inner rear quarters -- too bad, as some of these are prime rust out areas. After this point, some of the cars are detoured to become two tone jobs. They would then be masked and painted and returned to the line. Now an area behind the grill will be flat painted black. (Otherwise the parts behind the grill will show up as you look at it. When black, it blends in. I have seen a great many cars that must have missed this step, as they are still body color here). Next is a stop at the decal section, where stripes or wood graining will be applied. Then the cars are inspected. Any problems, they are pulled off the line and redone.
Meanwhile there is assembly going on elsewhere. The dashboard assembly and wiring harness are being put together. When the car passes the inspection, the heater (or AC), dash, and wiring harness are installed. The front and rear windshields are then installed from an overhead area, and the car is once again inspected. Now, it is beginning to look like something. Our next stop is the largest, the trim area. Here, the door windows, door panels and related parts, and exterior chrome are installed. Also, the door handles, wiper assembly, mirrors, bumpers, etc, are put in place. The car is also undercoated in this area, and the gas tank and fuel lines are added. O have seen gas tanks with and without undercoating, so I don't know which was supposed to be done first). Meanwhile, the steering columns were assembled, color matched, and installed. Master cylinder and brake lines ware also installed. By this time, everything around the dashboard has been installed, as well as the lights, and everything that bolts to the wheelwells under the hood is in place. The car is then put through a leak test. Water with a special dye is sprayed all over the car from every angle. An inspector in the car uses an ultra violet light to search for leaks. These are noted, but not repaired until the end of the line. It is at this point that the car is now transferred to the Main Assembly Plant in Kenosha, about 1.5 miles away. Special trucks haul these cars across town where they will be unloaded and placed on a new assembly line. (The Brampton built cars are all done at the same plant, so they just move on).
Now we are in the new plant, and ready for the final assembly. Things have not been idle here, though. The engines have all been assembled and test run. The same for the rearend, tranny, suspension, and brakes. The whole drivetrain is installed as one unit. The suspension and steering systems are assembled to the crossmember. The engine and trans are then mated to this assembly, along with the front brakes and tranny crossmember. The rear brakes are on the rearend, which is on the leafsprings. (With Torque Links, if so equipped). The driveshaft is also added, along with the remainder of the brake lines. This section is then mounted on a special stand and mated to the engine/suspension section. From here, the exhaust system is added. Now the most interesting part of the whole assembly, the power train to body assembly. The body section comes down a conveyor out of a second floor unloading area. The engine section also comes from a second floor level, suspended from the top. (Ever see those two holes in front and rear of the carb on your V8s? This is where the sling bolts to, with head bolt size bolts). The engine/suspension system hits ground level and is attached to the rearend section, sitting on a special stand. The two conveyor systems meet and the whole power train is assembled as a unit FROM UNDER THE CAR! ! ! And it takes 4 guys about 3 minutes to do it. Now we're nearing the end. The next area is the installation of the carpets and seats. The seats are assembled right there in the plant and fed onto a continuous conveyor. The tires, wheels, spare, etc. are added, and before you know it, the car is done. Now some gas is added, the brakes are checked, and just like that, the car starts up and drives to the Quality Control section at the end of the line. Here the car is driven on rollers at various speeds to check for any problems. Meanwhile, when this is happening, the front wheels are being aligned from underneath, and the headlights are aimed. If all checks out, the car is driven to a holding area to await transport. (This is where the 3 miles on the speedometer of a new car comes from. All cars are not taken on the test track). If there was a water leak or other mechanical problem, the car is driven to the staging area where a group of mechanics repair the problem. When done, it also goes to the holding area.
All this sounds pretty complicated, huh? Well, it is, but with the right programming, it isn't too bad. When each order is taken, a number of broadcast sheets are made for the car (all the same). These show codes that correspond to options on the car. This is hung on the car, and as it gets to each area, a quick glance will show color of car and interior, type of option, etc. It is also assigned a place in order on the final assembly line. This place corresponds to the same order given the power train and other lines. Now, if all goes right, the car ends up with the right options. Copies of these broadcast sheets are attached to the body, engine, rearend, upholstery, etc. Most were thrown out after use, but one may be occasionally found inside seat backs or under carpets.
There are about 10,000 parts in your car when finished. To have a car 99% perfect would mean there would be 100 broken or damaged parts. As most cars only have one or two problems, you can see the quality control of the assembly line was pretty good. Sure, there are problems such as ill-fitting carpets, but this is mainly a problem of the supplier, not the auto company.
One final comment: If you plan on doing a #1 Concours restoration of the car, you may find that assembling it like the factory did easier than other methods. Put your engine on the suspension, put this assembly on a shopping cart bottom, roll it under your car, and install it from the bottom. It really is much easier, and you do not have a problem damaging the firewall or other painted areas.
Here's a shot of the final assembly area borrowed from http://www.arcticboy.com/.
Be sure to visit the Atcticboy site for lots of AMC stuff, including AMC screensavers and
desktop icons, for both PC's and Macintosh platforms!
v990306