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I've always wanted to build a kit car, but hesitated for many years before making any firm decisions. I read car magazines and studied the literature of everything from dune buggies to super-car reproductions. Why did I decide on a Caterham Seven? I'd admired the Lotus "club racer" creation for many years: a fast car, emulating the "pur sang" Bugatti tradition of performance through light weight and ingenious design. And I thought that since hundreds of people had successfully completed one, the instructions and support must be pretty good: I might succeed as well.
I studied the Caterham websites for information, because I thought I'd have to order the car from England, as I'd ordered the Mini Cooper S JCW which is my daily driver. But then I talked with Jeff Sloan of British Auto Specialists (BritAuto) in Fort Worth, and found that he had a kit in stock at last year's prices, so I ordered it for delivery at the end of the semester (I was still busy teaching at Oklahoma State University). For an engine, Jeff referred me to Cody Story at Caterham USA in Denver, who agreed to build up a Zetec for me, starting with the parts from a Ford Focus SVT (Special Vehicles Team).
Jeff had sent me the assembly manual in advance, so I could get all pumped up about my project; it lays out the process step-by-step, like the old Heathkit manuals, but it is a good idea to read a few steps ahead. On the appointed day, his helper George delivered the kit: a pick-up truck bed full of boxes and wheels, plus an almost five-by-eleven foot crate, containing frame and body, on a trailer. Helpfully, he unscrewed dozens and dozens of deckscrews to open the box. The two of us, plus my racer friend Frank, carried the frame and basic body to the center of my garage, setting it on four jackstands, and then propped the other components against the walls. The ball was in my court now.
Jeff had suggested that I familiarize myself with the contents of all the boxes before starting. I was impressed by the brazing on the "birdcage" space frame from Arch Motor & Mfg., by the riveted aircraft-aluminum skin, and by the quality of the components throughout, but a little overwhelmed trying to keep track of all the parts.
First I mounted the front suspension: the A-arms pivot on thin rubber bushings bonded between the outer shell and an inner bushing. The attachment points are precisely located on the brazed space frame, so assembly is easy, requiring only the usual English sockets, plus a 7/32 Allen hex for the capscrew holding the lower end of the coil-over shock. One does need a torque wrench, and the optimal torques are specified in the assembly manual. It also pays to read LH and RH labels carefully: you don't want to interchange and flip the lower A-arms, and have the weight of the car hanging on a circlip. I didn't get stuck, until it came to getting off the big nut holding each stub axle so that I could slip on the bracket for the cycle fender. I decided to sleep on that before applying brute force.
I took this challenge as an excuse to buy and mount a vise with massive five-inch jaws. I already had a big cross-shaped tire wrench, one end of which fits the nut. Cushioning the jaws with slats of wood, I clamped each upright, and removed the nut with the big wrench. Then I was ready to move on, and started to fit the rack-and-pinion steering. All went smoothly until I was unable to find a grommet to seal the two-inch hole through which the steering column passes into the cockpit area. Rather than proceed without it and have to remove the shaft again later, I decided to switch to the rear suspension until I found the grommet.
The differential is very heavy, so holding it in place while lining it up with bolt-holes is almost impossible for a guy working alone. I had a two-step approach: mount the roll-over bar so that I could safely suspend the differential from it on a rope, and use a small hydraulic floorjack to maneuver it into exact alignment. When I got it bolted in with the prescribed stacks of washers, it turned out exactly centered, so I didn't have to play with shims. Attaching the propeller shaft required a metric 15-mm socket. The rear suspension is a De Dion axle located by multiple links, which I assembled step-by-step, until I got stuck again: one of the weld-nuts in the frame, for the end of the right-side rear link, was jammed, and I couldn't get the proper bolt very far into it. Time to sleep on it.
I googled the bolt, which was specified to be "Imperial (fine)", but could not find out what that means. However, the diameter and thread pitch are the same as "U.S. National Fine", so I carefully cleaned up the weld-nut with an SAE tap, and it worked great. The axle, the half-shafts, the bearings, and the disk brakes fit without a hitch, although I did have to buy a 41-mm socket from NAPA for the axle nut. I didn't get stuck again until I mounted the rear calipers: to center them properly, four 6-mm spacers are needed for the two mounting bolt on each side. I found only two; rather than substitute 6-mm stacks of washers, I called BritAuto, and they sent me two more in the next mail. While I was chatting with Bob, who has assembled six of these kits, I asked about the steering-shaft grommet, and he explained that there is a small plate which reduces the size of the hole to fit one of the smaller grommets, which solved that problem. I completed the steering and, when the spacers promptly arrived, finished the rear suspension and the handbrake. I could now bleed the brakes (with the help of my wife pushing the pedal), attach the wheels, and have a rolling chassis.
I had noticed that the throttle arm rubs lightly against the steering shaft, which doesn't seem right to me, and asked Jeff. He agreed with me and sent me a picture of the way they bend the arm to clear the shaft, so I got to use my big vise again.
About that time, the engine and transmission arrived by truck freight, mounted into a 56-by-31-inch crate. When I opened it, it also contained a big box full of electronic and computer parts such as engine wiring harness, central processor, oxygen sensors, etc., plus a supplementary manual. I had wanted to hold off on installing the engine until I had the chassis on four wheels, but the first page of the engine manual suggested that mounting the engine wiring harness would be easier before proceeding too far, so I thought it was time to read ahead.
The problem was that two connectors had to be fished back past the differential to the fuel pump, and there is not a lot of room for fingers to do that. I did not want to lower the differential again! Loosening the handbrake cable gave me enough space to use haemostats to pull and nudge the cabling through. The rest of the wiring harness and the engine computer were much easier to place. The engine preparation was simple except for overcoming a mental block on how the speedometer drive assembles; after another telephone call with Bob at BritAuto, that also turned out to be easy.
I was very anxious about lifting the engine into the car without damaging the car, the engine, or myself. I had planned to rent an appropriate lift, but it turns out that I have a very substantial roof support beam above the center of my garage, so I carefully rigged a lift using a heavy-duty "come-along" and chain borrowed from a friend who likes to work on trees. I lifted the engine, rolled the chassis under it, and gradually lowered the engine while rolling the chassis forward. With my wife helping to line things up, we engaged the drive shaft after I jacked up the rear so it could turn the wheels and align the splines. Next came the engine mounts, which required a little drifting to line up the bolts. When I had them all safely in place, I breathed a sigh of relief!
Once the drive shaft is inserted, you can fill the gearbox with oil. The manual warns that the filler plug is very difficult to replace with the engine in the car, and that turned out to be very true. I tried it unsuccessfully both from above and from below, while thinking up several schemes for making it easier. I even had my wife, who has nimbler fingers, crawl under the car! In the end, the most practical scheme proved to be unbolting the rear gearbox/engine mount, and prying the unit way to one side, to make more room.
An easier challenge was hooking up and bleeding the hydraulic clutch. The only problem was that the hydraulic union that the Caterham kit provides for connecting to the master cylinder does not fit the threads on the hose already connected to the engine by Caterham USA. I e-mailed Jeff, and he came through as always, mailing me the correct union.
The intake manifold and the exhaust pipes all fit precisely, except for having to re-bend the dipstick tube slightly to miss the nearest exhaust pipe. Ditto the coolant hoses and heater, except for having to rotate the steering rack slightly in order to keep the steering column from rubbing against the waterpump inlet hose. To keep things tidy, I had to re-locate the steering-column grommet plate at the firewall slightly.
All the electric connections for the engine computer, sensors, and operators took quite some time to locate (and Cody advised me by telephone, and warned me to tie the wires to the timing sensor well away from the exhaust headers!); but the only glitch was that I had trouble removing the oil-pressure switch on the engine to screw in an adapter instead, which connects to a braided hose to a remote pressure sensor to be mounted on the chassis ground post. This switch would have been a lot easier to unscrew before I installed the engine! Fortunately, removing the oil filter gives adequate access, and the Sears Tool Catalog sells a deep 24-mm socket that fits.
I put in all the fluids, and had a scare a few hours later, when gasoline started dribbling on the floor. I had done a less-than-perfect job of sealing the (unneeded) return-fuel connection on the tank, and as vapor pressure built up in the tank, it started to vent there. Apparently the return pipe siphons down into the bottom of the fuel tank, so it vented liquid rather than vapor. Removing the gas cap stopped the drip, but I didn't get under the car to reseal the connection until all the gasoline on the floor had evaporated -- I'm not into self-immolation.
Next came pouring two quarts of acid into the battery, which is shipped dry, and connecting the trickle charger. Once the battery was in the car, I went to the starting procedure: it didn't start! No fuel smell at the exhaust, and obviously no fuel being pumped to the engine. Time for some diagnostics ... between e-mail advice from BritAuto and Caterham USA, I figured out that the flasher relay had been put into the fuel-pump relay socket: when I put the right relays into the right slots, the car started right up!
From here on, with the running gear and the engine in order, the rest of the build was simple: add the seats, nose, fenders, etc., with just minor puzzles: how do you place the wire clips to hold the headlight glass in the headlight rim? What's the best way to ground the front turn signal lights? Where should I drill the holes in the front fenders, which were not pre-marked at the factory?
Using a Moroso pin wrench on the coil-over spring seats, I adjusted the suspension to ride at the high end of the suggested range, because of the oil-pan-grabbing road bumps in my area. I made sure that the front springs matched each other in length, and ditto for the rear springs, to avoid inadvertent "jacking" (heavier loading on one diagonal). After that, I put the final torque on the front suspension bolts. To make things easier to check for safety, I had gotten into the habit of putting a dab of fingernail polish on each bolt after torqueing it, positioning the marks consistently. A lot of "fixings" are assembled only finger-tight at first, and properly tightened much later in the assembly, so it would be easy to forget one. I have since learned that PegasusAutoRacing.com sells an "Inspector's Lacquer" which will show it more clearly if a nut later starts to vibrate loose.
Registering the car was much easier than I had feared. After some telephoning to the Title Consultants at the Motor Vehicle Department of the Oklahoma Tax Commission, they sent me Form 761 "Affidavit of Assembly and Ownership" (not listed on the website or known to local tag agents!), which I submitted together with the Manufacturer's Statement of Origin, the kit dealer's Bill of Sale, and the engine builder's Bill of Sale, to a tag agent who notarized my "Application for Oklahoma Certificate of Title for a Vehicle" Form 701-6. Six weeks later I got the call to bring insurance verification and a check for the Excise Tax, and got my license plate so I could legally drive it. A few weeks later I drove over to the tag agency to let them look at the VIN number on the chassis, before they would let go of the actual title document, which I will need if I ever sell the car.
Since then have been using the Seven to run my errands and to go for "blats." The only problem is that I don’t know what my next project should be: the Seven accelerates and handles so briskly that I can't find anything that will top it!
Peter Moretti -- Summer 2006
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