SECTION 8

FUEL TANK AND EXHAUST

CONTENTS OF THIS SECTION

General Description

The fuel tank on passenger car models, with a 16 gallon capacity, is mounted on the left side of the car and to the rear of the rear axle (fig. 1). Station Wagon and Sedan Delivery models have a 17 gallon fuel tank centered under the body and to the rear of the rear axle. These fuel tanks differ from the passenger car type in that they are kidney shaped rather than rectangular. Nine passenger Station Wagon fuel tanks are especially designed to leave room for the third seat and lower spare tire location. AU Station Wagon tanks are wider than in passenger models but allow for the installation of dual mufflers and tailpipes when desired.

NOTE: On units equipped with a power package, a 20 gallon fuel tank is used.

The tank assembly consists of two shallow pans, each with a wide flange, which are set face to face and seam welded at the flanges around the entire tank to assure leakproof construction. Exceptional stiffness is secured by the combination of the welded flanges and depressed ribs in each of the pans. All fuel tanks for 1957 are now equipped with a filler neck vent pipe and hose.

The tank is supported by two straps to the body. It is fitted with a tank gauge unit and a direct acting float, the movement of which is transferred to the tank unit rheostat contact by a link arm.

The filler neck is accessible through a spring loaded molding in the left rear fender on all models. A vented filler neck cap, easily removed, is retained on the rust proofed filler neck by a cam type lock on the outside diameter of the filler neck. This eliminates possibility of damage to the cam by careless handling of fuel hoses.

The fuel pick-up pipe is built integrally with the tank gauge unit, located at the top front center of the tank (fig. 2). On nine passenger station wagons, the gauge and pick-up pipe assembly is located at the top center rear of the tank. This easily accessible location places the pick-up pipe to fuel pipe joint near the top of the tank, in line with safety recommendations. A large area, fine mesh screen is located on the bottom of the fuel pick-up pipe. This screen is designed to prevent the entrance of dirt or water into the fuel system, and operates with a self-cleaning action.

Considerable attention has been given to locating the gasoline feed lines so as to reduce vapor lock to a minimum. On dual exhaust equipped models the main feed line is located on the outside of the right frame side rail-opposite side to the exhaust system, and passes up the fuel pump side of the engine to the carburetor. On all models without dual exhaust, the pipe is located on the inside of the right frame side member.

CAUTION: Always drain gasoline from complete fuel system including carburetor, fuel pump, all fuel lines and fuel tank if car is to be stored for any appreciable length of time. This precaution will prevent gum formation and resultant improper engine performance.

Gauge Unit or Fuel Strainer Replace

1. Drain gasoline from tank to a level below the gauge unit by removing pipe plug in bottom of tank.
2. Disconnect fuel feed line and gauge wire from unit.
3. Remove screws and remove unit. CAUTION: Be careful not to dislodge screen on end of pipe.
4. Clean screen, by blowing off with compressed air.
5. Reverse above procedure to install, installing mounting screws half way, hooking up feed pipe and then tightening the screws. The screen is held in place against the bottom of the tank.

1. Drain fuel tank.
2. Disconnect fuel pipe and gauge wire from tank unit.
3. Remove bolt holding filler neck to underside of floor panel from underneath car.
4. Pull filler neck out of tank.
5. Remove tank support straps and remove tank. NOTE: On six passenger station wagons and sedan delivery models, it will be necessary to remove both rear spring shackles, disconnect both rear shock absorbers and raise the frame and body for clearance. Procedure for fuel tank replacement an nine passenger station wagons is the same as for sedan models.
6. Installation is performed by reversing the above steps. NOTE: Use a new filler neck to tank seal.

The fuel lines should be inspected occasionally for leaks, kinks or dents. If evidence of dirt is found in the carburetor or fuel pump on a disassembly, the lines should be disconnected and blown out. Check the fuel strainer in the tank for damage or omission. AU fuel lines are of 5/16" diameter tubing. Joint must be of the double-lap flare type, constructed as shown in the Brake Section of this manual

Exhaust System

General Description

The exhaust system used on all single exhaust passenger car models includes an exhaust pipe and muffler assembly and a tail pipe that extends back to a point where gases are discharged below the rear bumper on the left hand side. An exhaust cross-over pipe is used on V-8 engine models to connect the two exhaust manifolds.

The dual exhaust system utilizes two exhaust pipe and muffler assemblies and two tail pipes. Each assembly is connected to a separate exhaust manifold and carries the exhaust gases to the rear and discharges them on each side of the rear bumper.

The passenger car muffler is 30 inches in length (fig. 3). An oval cross section provides a maximum ground clearance. The muffler is of all-welded construction, and contains three separately tuned resonance chambers. These chambers, used with the reverse flow and diffusion principle of muffling, suppress the periodic vibrations which tend to be set up in the exhaust system. The result is a reduction of passenger compartment resonance and quieter vehicle operation. The large capacity of the muffler keeps back pressure at a minimum for maximum engine efficiency.

All external parts of the muffler are electric are welded, while all internal parts are spot welded in position. This type construction makes premature failure or rattling practically impossible.

The center mounting, directly back of the muffler (fig. 4), is a vulcanized shear type rubber cushion design. This holds to a minimum the transfer of any exhaust vibrations to the frame and body. The rubber cushion is mounted to the muffler outlet pipe and the support is on a frame bracket. The muffler end of the tailpipe slides over the outlet pipe of the muffler and is held in place by a clamp. The back end of this tailpipe is clamped in a tail pipe support bracket. This bracket is attached through a shear type rubber mount to a separate bracket attached to the frame side rail (fig. 5).

Service

When installing an exhaust and muffler assembly or a tail pipe, care should be taken to have these parts in the proper relation with each other. Incorrect alignment of the exhaust system is frequently the cause of annoying rattles due to incorrect clearances. Unusual noises which are hard to locate, are sometimes due to a change or obstruction to the normal flow of gases through improper mountings.

There are three points to consider when installing an exhaust and muffler assembly or a tailpipe.

1. There should be 5/8" clearance between the underside of the floor pan and the tailpipe at the kick-up.
2. The tailpipe support must be in a vertical position. If it is at an angle, the tailpipe is apt to strike the bumper.
3. There should be sufficient clearance between the tailpipe and the shock absorber dust tube to prevent contact during operation.

To replace a muffler assembly, cut exhaust pipe as close to muffler inlet as possible, which will allow new muffler to be slipped over end of exhaust pipe.

If exhaust pipe has to be replaced it will be necessary to replace both the exhaust pipe and muffler with service replacement parts.

Convertible models carry a separate exhaust pipe and muffler.

On V-8 models, the exhaust cross-over pipe may be replaced without replacing the exhaust pipe.

Assembly Manual