Jeep Legend - Super Hurricane



The Super-Hurricane engine has widened the scope of the entire Willys utility line. Many customers need the power that only this engine can supply. Once again, power being the most important engine characteristic, will be covered first.


The six-cylinder L-head Super-Hurricane engine is the result of the latest technical research coupled with a time tested prototype engine proven under the most difficult operating conditions. Vibration and friction, the two great enemies of smooth performance and engine wear, have virtually been eliminated. The new Super -Hurricane will deliver 115 Horsepower with a maximum torque of 190 ft. pounds, from its 226 cubic inch displacement and 6.86-1 compression ratio. Yet the Super-Hurricane runs on regular gasoline for greater economy. The dual down-draft carburetor and dual intake manifold insure maximum use of the fuel available. The result -- top performance to handle the rough jobs, long life and power to meet the stiffest requirements.



The cylinder head of the new Super-Hurricane engine is an iron alloy casting of the same metallic composition as the engine block. Since it expands and contracts with the block, the possibility of warping or cracking from such causes is eliminated.

The Super-Hurricane combustion chamber is designed to provide a high compression ratio of 6. 86-1. This ratio allows an extremely high power output along with noticeable gasoline economy.

When this engine is used at altitudes of 5000 feet or more and a good grade of gasoline is available a special 7.3 to 1 cylinder head is recommended.  This high power output make i t necessary for the volumetric capacity of the combustion chambers to be absolutely uniform. An electrosonic device, developed for this purpose, measures every cylinder head and points out any minute differences. To further assure identical pressures in each cylinder, cylinder walls are reamed and honed to a mirror-like finish, demanding surface variations of less than 20 millionths of an inch. Actually, the dimensional tolerances of both cylinders and pistons are kept to 5 ten-thousandths of an inch. Smooth vibrationless, frictionless operation is the result.


The cylinder block of the new Super-Hurricane is heavier and stronger in the upper crankcase portion. It has greater webbing strength and heavier main crankshaft bearing caps. This gives the engine resistance to sudden strains and periodic shocks.

Cylinder barrels are completely separated from each other by full length water jackets which surround the entire cylinder. Uniform cooling of the cylinder barrels for the full length prevents warping or twisting which might result from uneven temperatures because of varying thickness of the metal. This is the most expensive method of casting a cylinder block. However, its advantages in stability, long life, operating economy and smooth performance more than justify its use.


Valves are designed and timed to increase volumetric efficiency and power.  The intake valves are silchrome alloy and seat at 30° angle. New silchrome SRC steel exhaust valve s seat at 45' angle to facilitate the scavenging of exhaust gases. Positive rotors are used on the tappet end of the exhaust valves causing them to turn, thus aiding in the elimination of sticky valves and insuring smooth, perfectly synchronized valve action.

The Super-Hurricane engine has new mushroom shaped tappets providing extremely large cam bearing surfaces. This reduces noise and gives better vertical alignment over many years of operation. The tappets are individually lubricated under pressure through specially drilled oil passages which lead directly from the main oil manifold system.


Newly-designed, tin-plated, aluminum alloy, T-slot pistons are used in the Super-Hurricane engine.  A cast-in-steel thermal expansion control ring forces the piston to attain perfect roundness through heat alone rather than by the pressure of the expanding metal on the cylinder walls. This reduces scuffing, scoring and piston slap to a minimum.

The Super-Hurricane has two compression rings and two oil control rings which are slotted so excess oil can drain back to the crankcase. This ring combination reduces piston and cylinder scuffing and gives better oil control with prolonged engine life and top performance.


Connecting rods are forged from special steel, hardened and carefully balanced over their entire 7-inch length for perfect weight distribution. The cylinder walls and the piston pin bushings are lubricated by an oil jet hole in the lower end of the connecting rod. Oil is squirted under pressure at each revolution when this hole lines up with the drilled oil passages which lead directly from the main oil manifold system.


The new dual throat carburetor plus the dual intake manifold system, with an automatic pre-heater for cold weather warm up, assures each cylinder of the largest possible charge of perfectly mixed fuel. Each throat of the dual carburetor supplies vapor to a separate manifold, and each manifold, in turn, passes the vapor to only three cylinders. The manifolds are of large diameter, and f r e e from bends or obstructions of any kind. This cuts down the travel distance for the fuel mixture. Each cylinder receives an exactly equal charge which makes for smoother performance.

The three -valve oversize fuel pump and large carburetor bowl capacity protects the Super-Hurricane Engine against vapor lock.


The crankshaft is forged steel and weighs 77 pounds. The new counterweight design permits 100% static and dynamic balancing.  A new crankshaft oil seal design has been developed to eliminate oil leaks from the crankcase to clutch housing.


Valve chambers and cylinder heads have ample cooling, and large radiator capacity (12-quart cooling system) gives a high margin of safety.

A thermostat, installed in the cylinder head outlet pipe, controls the flow of the coolant to the radiator at all times. The curved-tip 18" fan blade assures a cooler, quieter engine.

The cooling system is engineered so that the operating temperature range is reached quickly and maintained evenly whatever the conditions of roads, weather or altitude.


Oil is drawn from the oil pan through a floating oil screen by a large submerged pump, gear driven from the camshaft at a constant pressure of 35 pounds per square inch to the main oil gallery. From there it passes through the oil filter and under pressure lubricates all main connecting rod, and cam shaft bearings, as well as all tappets, timing chain and sprockets.

Cylinder walls, pistons and piston pins are splash lubricated by being sprayed with oil even at low speeds from spurt holes on the thrust side of the connecting rod bearings.

This concludes the main features of the Hurricane and Super-Hurricane engines. However, it would be well to go into more detailed technical specifications. This, plus detailed information on the fuel, electrical, cooling and lubricating systems, is included along with the complete engine specifications in the following pages of this section.


01  Fan

17  Camshaft

02  Water pump assembly

18  Rear engine plate

03  Piston Pin

19  Oil pan drain plug

04  Water outlet fitting

20  Oil float support

05  Cylinder head

21  Oil float

06  Piston

22  Oil pan assembly

07  Oil level indicator assembly

23  Connecting rod

08  Carburetor assembly

24  Cranks haft kit

09  Spark Plug assembly with gasket

25  Crankshaft gear

10  Exhaust Valve

26  Crankshaft oil seal

11  Exhaust Guide

27  Engine front plate assembly

12  Exhaust Spring

28  Pulley

13  Adjusting valve screw

29  Timing gear assembly cover

14  Block and Bearing

30  Timing shaft gear

15  Flywheel and dowel bolt kit

31  Drive fan belt

16  Valve tappet