Rochester Monojet Carburetor

The 1MV monojet carburetor is a single down draft unit using a triple ventuir in conjunction with the plain tube nozzle. The main venturi is 1 7/32″ in diameter and the throttle bore is 1 7/16″.
Fuel flow through the main metering system is controlled by a main well air bleed and a fixed orifice jet. A venturi velocity power enrichment system is used to provide good performance during moderate to heavy acceleration and at higher engine speeds.
An exhaust gas recirculation, E.G.R. system controls oxides of nitrogen emissions. The E.G.R. valve is operated by a vacuum signal taken from the carburetor throttle body.
A vacuum supply tube installed in the carburetor throttle body connects by a passage to timed vertical ports located in the bore of the throttle body and float bowl. The ports provide a vacuum signal to the E.G.R. valve in the off idle and part throttle operation of the carburetor.
The E.G.R. valve, mounted on the intake manifold, circulates a metered amount of exhaust gases to the combustion mixtures to lower peak combustion temperatures, thereby reducing oxides of nitrogen during these ranges of engine operation.

The E.G.R. system is not in operation during the engine idle.

A pleated internal paper fuel inlet filter is mounted in the float bowl behind the fuel inlet nut to give maximum filtration of incoming fuel.

The carburetor has an aluminum throttle body, a thick throttle body to bowl insulator gasket, and a internally balanced venting through a vent hole in the air horn which leads into the bore beneath the air cleaner. The float bowl is externally vented under extreme conditions through a pressure relief valve system.

The carburetor part number is stamped on vertical section of float bowl, next to fuel inlet.

An idle stop solenoid is used to control idle. The solenoid is electrically  controlled through the ignition switch. When the ignition switch is tunred off, the solenoid is denergized, allowing the carburetor throttle valve to close further, preventing the engine from running after the ignition switch is turned off. On manual transmission models, the  solenoid also deenergizes when the clutch is disengaged.

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Why the Tucker Was “The Car of Tomorrow”

The Reason Why the Tucker Was “The Car of Tomorrow”
It’s sad to see great ideas suddenly coming to a sudden death due to different political, economic or financial issues. While our free world tends to believe everyone should be able to pursue their dream, this isn’t always the case. A good example for such a sad scenario was Preston Tucker, the designer and developer of Tucker automobiles.
How it all started

Tucker_torpedo_patent
Since the Second World War was over, the globe was ready for a change, for new developments and out of the box thinking. Everyone in the US was waiting for new vehicles to buy; however none of the three leading automakers did something to fulfill the ongoing demand.
The newest vehicle someone could own at that particular moment was at least 7 years old, as nothing new was produced since 1941.
This particular idea crisis led to the growth of smaller automakers which, although were working on providing new models, many of the features were still inspired from the already existing products. This is where Preston Tucker had the advantage, as he designed a vehicle with a design out of its time.
A completely new car

Tucker
Tucker brought up a car concept built from scratch. It included a flat-6 cylinder rear mounted engine, rear wheel drive and independent suspension. Some of these features may actually sound as being contemporary, but this was all happening almost 60 years ago.
For safety purposes, a perimeter frame surrounds the whole vehicle in order to absorb crash forces and a roll bar was included discreetly in the roof. The steering box is strategically positioned behind the front axle of Tucker, to protect the driver in case of an accident.
Windshield and windows were made from shatter-proof glass designed to be easily removed in case of an unfortunate accident, facilitating the emergency exit of the driver and passengers.
When saying that Tucker 48 was a new car, it is not only about the new features included in the limited 51 piece series. 1948_Tucker_Sedan_at_the_Blackhawk_MuseumIn fact, every car was different from the one before and the one going to be built after her. Preston Tucker improvised on the move, adding and testing new concepts as Tucker 48 vehicles were rolled out the factory.
Difficulties
The uncover of the first Tucker 48 prototype in Chicago back in 1947 was doomed in front of over 3000 people as various issues popped up in the last minute and couldn’t be fixed in time for presentation. Among these, suspension arms popped under the heavy weight of the vehicle, the engine was incredibly loud and only developed around 80hp of the promised 150.
Although the original torque converting gearbox mounted on the first Tucker 48 prototype had no mean of going in reverse, Preston Tucker followed his intent of building a new transmission system. With help from Warren Rice, the inventor of Buick Dynaflow, the Tuckermatic was invented. It consisted of just 27 parts, double torque converters reducing everything to just one forward and one reverse gear. Three versions of the Tuckermatic were built: R1, R2 and R3. The first one never saw its way onto an engine as it required the motor to be turned off in order to switch gears.
The fall
Since the need of capital was constantly increasing as Tucker 48 was moving on with development, Preston Tucker started selling Tucker 48 accessories through his Tucker Accessories Program even before the vehicle was finished. This caused an investigation by U.S. Securities and Exchange Commission and the United States Attorney.
Although charges were eventually dropped, there was enough negative publicity to drown Preston Tucker’s project and cause only 51 Tucker automobiles to see the light of day. Fortunately, many of them are still in great condition and can be seen in various auto shows.

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