Reviving
&
DRIVING
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Tucker #1026
Editor’s Note: This article is the second in a multi-part series documenting the endeavor to “revive and drive” Tucker #1026 in time for participation in the Pebble Beach Concours d’Elegance.
(Previous page) Mark Lieberman driving Tucker #1026.
The Tuckermatic: Part Two By Mark Lieberman
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s the previous installment of our story concluded, we recognized that removing the fuel tank of Tucker #1026 was necessary. Extracting the tank posed several challenges. #1026 was the first “front tank” car, and some of the fixtures used, along with the dimensions of the space allocated, were yet to be determined. To safely extract the fuel tank for cleaning and sealing, we removed the entire front clip carefully. On a Tucker, this includes the luggage tub as well. Our team meticulously taped off the edges to protect the paint and unbolted the bumper, fenders, and tub. We slowly removed each piece to expose the fuel tank. At this point, extracting the tank was as simple as removing the straps, and out it came. We sent the tank to a specialist to boil it out and coat it for long-term protection.
The Fuel Tank Exposed fuel tank ready for removal Fresh fuel tank installed
Building the Suspension Through Trial and Error Next, we shifted our focus to the suspension. The original Torsilastic tubes were still in place but had long since perished. The collapse of the tubes was a common issue for the suspension. Tucker had three tube suppliers: BF Goodrich, Firestone and United States Rubber. The tube design exhibited issues from the beginning. The technology for bonding the rubber to the steel was not very advanced, and vehicles experienced frequent suspension settling or collapse.
Suspension Original rear Torsilastic tubes, trailing arms
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The Suspension
Original front Torsilastic tube, control arm and clamps New Front Torsilastic tube
In theory, the concept was innovative: Replace the steel springs with a compact rubber torsion bar that would provide a smoother ride and have limited adjustability. Execution of the concept encompassed a series of iterations. The first attempts were on the test chassis and Tin Goose. Two small rubber impregnated pucks were used on each upper control arm. The pucks proved insufficient to suspend the car under stress. Next, a revised design incorporated the use of a 12.5” tube to suspend each corner of the car. The new suspension system—first employed on #1001—used steel inner tubes bonded to molded rubber. The tubes, in turn, were bonded to an outer steel tube. The outer tube clamped to the chassis, and the inner tube connected to the control arm (front) or trailing arm (rear). The redesigned tubes performed much better than the puck design. However, unpredictable handling due to complicated linkage connecting the tube to the front suspension presented a new challenge. Ultimately, the Tucker team would utilize a rubber shear plate design for the front of the car instead of the rubber torsion bar for cars #1002 - #1025. The rubber shear plate significantly improved handling but provided no adjustability and was prone to rubber bond failure as well. The #1026 Suspension Beginning with Tucker #1026, a new, simpler design allowed for the use of rubber torsion bars in the front. The change provided the adjustability desired, but handling continued to present a problem. They addressed the issues on some cars at the Indiana Motor Speedway highspeed trials. Cars, such as #1029 (Preston’s car), received anti-sway bars and stability bars. To correct the collapsed suspension on #1026, we removed the original Torsilastic tubes. The front tubes unbolt from the lower control arms and slide out of their retaining clamps. We replaced them with new units of our own manufacture that duplicated the appearance
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of the originals and performed to the original specifications. A threaded hole was machined in the retaining clamp and located to accept a locking pin. Once these were in place, it was just a matter of sliding the new tubes in place and adjusting them to the correct ride height. The rear Torsilastic units proved more complicated than the front units. The center tube was welded to the rear trailing arms. To remove the original units, we machined the weld off and recentered the hole to accept the replacement tubes. A special jig was employed to ensure proper alignment. Also, the new units must remain cool while they are welded in place to protect the rubber from overheating. Once complete, locking pin holes were machined and threaded, and the new units were installed. Before final assembly, we inspected the rear axle shafts for cracks (another common issue) and replaced all of the axle bearings and seals. The bearings and seals ensured proper, smooth operation. Once all four Torsilastic tubes were in place, #1026 was standing tall. The final ride height adjustments were made following reinstallation of the front clip. #1026 Brakes and a Surprise We then turned our attention to the brakes. The master cylinder was dry, and each of the wheel cylinders was locked solid with corrosion. The brake shoes were old and cracked but not worn. We elected to replace them along with the bearings and seals. In addition to the master cylinder, the wheel cylinders and brake lines required replacement. We also observed that there was an additional brake line T-ed from the rear brakes to a hydraulic cylinder mounted on the upper section of the Tuckermatic Transmission. When the brakes were applied, the brake line would depress a rod that went into the transmission. With the help of Mike and Sean Tucker, research in the Cammack archives revealed original blueprints for R1, R2, and R3 Tuckermatic Transmissions. These prints gave us a clear look at the inner working of the transmission.
Engine Left: Engine before work performed Right: Engine ready to run
From Stan Gilliland, we were surprised to learn that the #1026 had a third pedal on the floor near the seat bottom. The pedal was depressed with the left heel of the driver. I have no idea how anyone over 5’ 4” could do this. We located the mounting holes for the pedal and the remnants of a bracket. We don’t know if it was hydraulically- or cable-actuated because no blueprints were located. Stan informed us that depressing the pedal would stop the external torque converter from spinning, allowing the driver to shift from forward to reverse with the engine running. That might have been what the previous mechanic was trying to accomplish with the added line off of the rear brakes. We determined that this modification created an unsafe operating condition. It depleted the liquid displacement capacity of the master cylinder because additional fluid was needed to fill and expand the extra wheel cylinder. We omitted the brake line and ran a series of experiments with a separate source of actuation (I’ll detail that for you later in the article). At this point, we completed the rebuild of the braking system, and #1026 was finally able to stop safely. When the brake system is working correctly, it’s very effective. Under hard braking conditions, the weight shifts forward due to the rear suspension design. The weight shift allows the front brakes to grab harder and reduce the chance of the rear wheels locking up. The combination of factors resulted in reduced stopping distances compared to other vehicles of the time.
Waking up the Engine Our next task was to wake up the 335 engine. After draining and inspecting all of the fluids, we were very encouraged. Everything looked pretty good. Fresh spark plugs, points, and a condenser began the process. The carburetor was removed and rebuilt. The mechanical fuel pump was absent and replaced with an electric pump. Adding the electric pump was a standard change for many of these cars. It was a long distance from the fuel tank to the mechanical pump. Since the distance could be problematic, we employed the electric replacement pump. The previous unit was as crispy as burnt toast. Fresh oil and coolant were installed, and we carefully rotated the engine by hand for a few revolutions. Everything looked, sounded, and felt very good. We next checked the fluids in the transmission (we would attend to this further in the process), they looked good in the body of the trans. A few deteriorated wires were replaced, and we installed a fresh battery.
Brakes Corroded wheel cylinder Reconditioned brakes
With the new battery in place, we checked the electrical system. The lights, turn signals, and gauges checked out properly. Everything powered up and was in good order. Before the engine could be fired up, we reinstalled the freshly reconditioned fuel tank, installed a fuel line, new fuel tank sending unit, and re-fitted the front clip. Everything went together beautifully. We then replaced the oil pressure sending unit. We were ready to bring this engine to life! n
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