Accessory drive for outboard motor

A drive arrangement for an engine positioned within a cowling of an outboard motor and powering a water propulsion device of the motor is disclosed. Preferably, the engine is of the "V"-type, having first and second banks and an intake and exhaust camshaft corresponding to each bank. A drive arrangement is provided for driving the camshafts off of a crankshaft of the engine. Preferably, a flexible transmitter is positioned at a bottom end of the engine and directly drives one camshaft of each bank from the crankshaft, with the other camshaft of each bank driven by the driven camshaft.

FIELD OF THE INVENTION 
The present invention relates to an engine of the type utilized to power an 
outboard motor. More particularly, the invention is a drive arrangement 
for camshafts and other accessories of an engine positioned within a 
cowling of an outboard motor and powering a water propulsion device of the 
motor. 
BACKGROUND OF THE INVENTION 
Outboard motors which are used to propel watercraft are positioned at the 
stern of the watercraft, generally attached to the transom. These motors 
comprise a cowling which houses an internal combustion engine. The engine 
is arranged to drive a water propulsion device of the motor, such as a 
propeller. 
The motor is connected to the watercraft in a manner which permits the 
motor to turn from side-to-side about a vertically extending axis for use 
in steering the watercraft. In addition, the motor is tiltable about a 
generally horizontal axis for use in trimming the motor. 
Because the motor is movably mounted to the craft, it is desirable for the 
motor to be as small as practical. It is, therefore, an object of the 
present invention to provide an engine which is compact in arrangement. 
In addition, if the motor extends far beyond the rear of the watercraft, 
its center of gravity is far offset from the horizontal axis about which 
it tilts, making it very difficult to tilt the motor. Also, moving the 
center of gravity of the motor far from the stem of the watercraft affects 
the dynamics of the watercraft. 
It is therefore another object of the present invention to provide an 
engine having a center of gravity positioned such that when the engine is 
used to power a motor connected to a watercraft, is close to the 
watercraft. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, there is provided an outboard 
motor having a water propulsion device which is powered by an internal 
combustion engine. The engine has a drive arrangement for driving at least 
one camshaft. 
Preferably, the engine is positioned within a cowling of an outboard motor 
and is arranged so that a crankshaft thereof is generally vertically 
extending. The engine has at least one combustion chamber and a member 
movably mounted in the combustion chamber for driving the crankshaft. An 
intake passage leads into the chamber and an exhaust passage leads from 
the chamber. Valve means are provided for selectively closing at least a 
portion of the intake and exhaust passages. Preferably, at least one 
camshaft actuates said first and second valve means. 
A drive arrangement is provided for driving each camshaft from the 
crankshaft. In a first embodiment, a flexible transmitter is positioned at 
a bottom end of the engine and directly drives at least one camshaft. 
Preferably, the engine is of the "V" type, having a first bank defining at 
least one combustion chamber and a second bank defining at least one 
combustion chamber, with at least one camshaft is provided corresponding 
to each bank. In this arrangement, the flexible transmitter is arranged to 
directly drive one of the camshafts of each bank. In a preferred 
embodiment, an intake and exhaust camshaft is provided corresponding to 
each bank. In a first arrangement, the flexible transmitter is arranged to 
drive the intake camshaft of one bank and the exhaust camshaft in the 
other bank. In a second arrangement, the flexible transmitter is arranged 
to drive the exhaust camshaft of both banks. In either arrangement, timing 
drive means are provided for driving the camshaft of each bank which is 
not directly driven by the camshaft which is. 
In another embodiment, the flexible transmitter is positioned at the top 
end of the engine below a flywheel connected to the top end of the 
crankshaft. A pulley is preferably positioned above the flywheel, and a 
flexible transmitter extends in driving engagement with the pulley and an 
engine accessory, such as an alternator. 
Further objects, features, and advantages of the present invention over the 
prior art will become apparent from the detailed description of the 
drawings which follows, when considered with the attached figures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
In accordance with the present invention, there is provided an outboard 
motor 20 powered by an engine 22 and having an engine component or 
accessory drive arrangement in accordance with the present invention. The 
engine 22 having the drive arrangement system is described for use with an 
outboard motor 20 since this particular application is one requiring the 
compact arrangement of the engine 22 described. It should be understood, 
however, that the engine 22 may be used in other applications. 
As illustrated in FIG. 1, the outboard motor 20 is of the type utilized to 
propel a watercraft 24. The outboard motor 20 has a powerhead area 26 
comprised of a lower tray portion 28 and a main cowling portion 30. The 
motor 20 includes a lower unit 34 extending downwardly from the cowling 
portion 30. The lower unit 34 comprises an upper or "drive shaft housing" 
section 38 and a lower section 40. 
The powerhead area 26 of the motor 20 is connected to a steering shaft (not 
shown). The steering shaft is supported for steering movement about a 
vertically extending axis within a swivel or steering bracket 44. The 
swivel bracket 44 is connected by means of a pivot pin 46 to a clamping 
bracket 48 which is attached to a transom portion 32 of a hull 36 of the 
watercraft 24. The pivot pin 46 permits the outboard motor 20 to be 
trimmed and tilted up about the horizontally disposed axis formed by the 
pivot pin 46. 
Referring to FIGS. 1, 2 and 5, the power head 26 of the outboard motor 20 
includes the engine 22 which is positioned within the cowling portion 30. 
The engine 22 is preferably of the six-cylinder, four-cycle variety, and 
is arranged in a "V" fashion. In this arrangement, the engine 22 has a 
cylinder block 52 with a first cylinder head 53 and a second cylinder head 
54 connected thereto and cooperating therewith to define first and second 
cylinder banks 55,57 defining a valley therebetween. This valley faces 
away from the watercraft to which the motor 20 is attached. Each bank 
preferably defines three cylinders 59, each having a combustion chamber 
58. As may be appreciated by those skilled in the art, the engine 22 may 
have a greater or lesser number of cylinders, such as two, four, or eight 
or more. 
As illustrated in FIG. 5, a piston 66 is movably positioned in each 
cylinder 59, each cylinder lined with a cylinder sleeve 51. Each piston 66 
is connected to a connecting rod 68 extending to a vertically extending 
(i.e. along a vertical axis "V" as illustrated in FIG. 1) crankshaft 56. 
Referring to FIG. 2, the crankshaft 56 is connected to a top end 65 of a 
drive shaft 60 which extends downwardly through the lower unit 34, where 
it drives a bevel gear and a conventional forward-neutral-reverse 
transmission 61. A control (not shown) is preferably provided for allowing 
an operator to remotely control the transmission from the watercraft 24. 
The transmission drives a propeller shaft 63 which is journalled within the 
lower section 40 of the lower unit 34 in a known manner. A hub 62 of a 
propeller 64 is coupled to the propeller shaft 63 for providing a 
propulsive force to the watercraft 24 in a manner well known in this art. 
The crankshaft 56 is journalled for rotation with respect to the cylinder 
block 52. A crankcase cover 67 engages an end of the block 52 generically 
opposite the heads 53, 54, defining therewith a crankcase chamber 69 
within which the crankshaft rotates. The crankcase cover 67 may be 
attached to the cylinder block 52 by bolts 71 or similar means for 
attaching known to those skilled in the art. The crankcase chamber 69 is 
positioned generally opposite the heads 53,54 and on the side of the 
engine closest to the watercraft 24. 
The engine 22 includes an air intake system 72 for providing air to each 
combustion chamber 58. The intake system 72 is preferably positioned at 
the crankcase or watercraft end of the engine 22. As illustrated in FIGS. 
1 and 2, air passes through a vent (not shown) in the motor cowling 30 and 
into a main intake pipe 74. As best illustrated in FIG. 2, a throttle 116 
is provided for controlling the flow of air into the combustion chambers 
58. Preferably, the throttle 116 comprises a moveable plate positioned 
within air intake pipe 74, such that the intake pipe 74 may be generally 
referred to as a throttle body. The throttle 116 is preferably controlled 
through a cable by the operator of the watercraft. 
Branch pipes or passages 75 lead from the main intake pipe or throttle body 
74 to first and second surge tanks 76 having branches 78 extending 
therefrom. The branch pipes 75 may be formed separately or integrally with 
the throttle body 74. Preferably, each surge tank 76 has three branches 78 
extending therefrom, one for each cylinder 59 in a bank. Each branch 78 
extends to a passage 80 in the cylinder head 53,54 leading to one of the 
combustion chambers 58. 
Referring still to FIG. 5, means are provided for controlling the flow of 
air into each combustion chamber 58. Preferably, this means comprises at 
least one intake valve 82 corresponding to each intake passage 80. As 
illustrated, all of the intake valves 82 for each bank of cylinders are 
preferably actuated by a single intake camshaft 84. The intake camshaft 84 
is mounted for rotation with respect to its respective cylinder head 53, 
54 and connected thereto with at least one bracket. Each intake camshafts 
84 rotates within an enclosure defined by the cylinder head 54, 55 and a 
camshaft cover 88, and is rotatably connected to its respective head 54, 
55 via one or more bearings or journals 185 (See FIG. 8). The drive 
arrangement by which the camshafts 84 are rotated is described in detail 
below. 
Each valve 82 has a head which is adapted for seating against a valve seat 
in the passage 80, and a stem extending from the head through a valve 
guide 81 to a follower 83. A spring 85 is positioned between the follower 
83 and a portion of the cylinder head 53, 54 for biasing the valve 82 
upwardly into a closed position. 
An exhaust system is provided for routing the products of combustion within 
the combustion chambers 58 to a point external to the engine 22. In 
particular, an exhaust passage 90 leads from each combustion chamber to a 
passage 92. The remainder of the exhaust system is described in more 
detail below. 
Referring still to FIG. 5, means are also provided for controlling the flow 
of exhaust from each combustion chamber 58 to its respective exhaust 
passage 90. Preferably, this means comprises at least one exhaust valve 
96. Like the intake valves 82, the exhaust valves 96 of each cylinder bank 
are preferably all actuated by a single exhaust camshaft 98. Each exhaust 
camshaft 98 is journalled for rotation with respect to its respective 
cylinder head 54, 55 and connected thereto with at least one bracket. Each 
exhaust camshaft 98 is enclosed within the camshaft cover 88. The drive 
arrangement by which the camshafts 98 are rotated is described in detail 
below. 
As with the intake valve 82, each exhaust valve 96 preferably includes a 
head for selective positioning against a valve seat in the passage 90. A 
stem extends from the head of the valve 96 through a valve guide 97 in the 
cylinder head 53,54. A follower 99 is positioned at the opposite end of 
the stem for engagement by the camshaft 98. A spring 101 is positioned 
between the follower 99 and the cylinder head 53,54 for biasing the valve 
96 into its closed position. 
The flywheel 104 is preferably maintained in position on the top end of the 
crankshaft 56 with a nut 105. The flywheel 104 is preferably positioned 
under a flywheel cover 107. 
As best illustrated in FIG. 1, an exhaust guide 122 is positioned at the 
bottom end of the engine 22. The exhaust guide 122 has a passage 124 
extending therethrough which communicates with the exhaust passages 92 in 
a manner described in more detail below. An exhaust pipe 126 is connected 
to the bottom side of the exhaust guide 122 in alignment with the passage 
124. The exhaust pipe 126 terminates within a chamber of a muffler 128. 
Referring also to FIG. 3, the muffler 128 is positioned within the lower 
unit 34 and between the drive shaft 60 and a cooling liquid return. An 
exhaust gas outlet is provided in the bottom end of the muffler 128, 
through which the exhaust gas is routed (in the direction of arrows "E") 
through the hub 62 of the propeller 64 to a point external of the motor 
20, as best illustrated in FIG. 4. 
A fuel delivery system is provided for delivering fuel to each combustion 
chamber 58 for combustion therein. As the fuel system does not form a 
portion of the present invention, it is not described in detail. A 
suitable fuel delivery system as well known in the art may be employed. 
Such a delivery system may include a low pressure pump which pumps fuel 
from a supply through a filter to a vapor separator. The fuel may then be 
delivered by a high pressure pump under pressure into a high pressure fuel 
line, and thereon to fuel rails having passages leading to fuel injectors 
114. Preferably, an individual fuel injector 114 is provided corresponding 
to each cylinder 59. 
A suitable ignition system is provided for igniting an air and fuel mixture 
within each combustion chamber 58. Such systems are well known to those 
skilled in the art, and as the ignition system forms no part of the 
present invention, such is not described in detail herein. The ignition 
system may include a spark plug for use in igniting the air and fuel 
mixture within each combustion chamber 58. 
A cooling system is provided for cooling the engine 22. Referring to FIG. 
1, cooling liquid, preferably water from the body of water in which the 
motor 22 is positioned, is pumped by a water pump 130 positioned in the 
lower unit 34 through a water inlet 131. The pump 130 is preferably driven 
by the drive shaft 60, and expels the cooling liquid upwardly through a 
cooling liquid pipe 132. The coolant flows through the supply pipe 132 
from the pump 130 to the coolant jacket 133 for cooling the areas of the 
engine 22 surrounding the exhaust passage 92. The cooling liquid then 
passes into a number of cooling liquid passages 135 throughout the 
cylinder heads 53,54 and then to coolant jackets 137 around the cylinders 
59 in the cylinder block 52. 
A pressure valve (not shown) may be utilized to divert coolant through a 
relief passage and thereon to the coolant drain system in the event the 
coolant pressure exceeds a predetermined high pressure. 
In addition, a thermostat (not shown) may be positioned along the coolant 
path for monitoring the temperature of the coolant. The thermostat may be 
provided so that if the coolant temperature is high, a valve corresponding 
to the thermostat is opened and coolant is allowed to flow though the 
engine 22 at a high rate, but if the temperature of the coolant is low, 
then the valve is closed, allowing the engine to warm up. 
After being routed through the cylinder block 52 and heads 53, 54, the 
cooling liquid is preferably routed to a generally vertically extending 
return passage 139 through the cylinder block 52 (illustrated 
schematically in FIG. 1), for draining the cooling liquid to the bottom of 
the engine 22. The coolant is then split. Referring to FIG. 3, a first 
amount of coolant is directed to a coolant pool 139 surrounding an oil 
reservoir or pan 134, and another pool 141 near the muffler 128. When the 
liquid level in the pool 141 becomes to high, the cooling liquid runs over 
an overflow ledge or weir to a passage leading to a drain. The cooling 
liquid diverted to the drain is discharged from the motor. 
The remaining amount of coolant is directed around the exhaust pipe 126 for 
cooling it. This coolant then flows into the muffler 128, where it is 
mixed with the exhaust gas. The coolant is carried with the exhaust gas 
through the propeller hub 62 discharge back to the body of water. 
Preferably, the engine 22 includes a lubricating system for providing 
lubricant to the various portions of the engine in accordance with the 
present invention. Referring to FIGS. 1-3, the lubricating system includes 
the oil reservoir 134 positioned below the engine 22. The reservoir 134 is 
in communication with an oil pump 136 via a suction tube 138. The oil pump 
is drivingly positioned on the end of the crankshaft 56 at the bottom of 
the engine 22. Seals are provided for sealing the oil pump with respect to 
the remainder of the engine 22. The oil pump draws lubricant from the 
reservoir 134 and then delivers it through a connecting passage to a main 
gallery 142. Branch passages 144 extend from the main gallery 142 for 
providing lubricant to crankshaft bearings and the like. The oil 
preferably flows, with the aid of gravity, back into the reservoir 134 
from the engine 22. 
As illustrated in FIG. 5, the engine 22 may include additional engine 
auxiliary features or accessories such as a starter motor 146 and an 
alternator 148. Preferably, the starter motor 146 is positioned for 
engagement with the flywheel 104 for use in starting the engine 22, as is 
well known to those skilled in the art. 
The alternator 148 is preferably utilized to produce electricity for firing 
the spark plugs and similar functions. The alternator 148 is run by a belt 
150 which is driven by a pulley 149 mounted on the end of the crankshaft 
56 just below the flywheel 104. In the embodiment illustrated, the pulley 
149 is actually connected to a downwardly extending flange portion of the 
flywheel 104, but vibration isolated from the flywheel 104 with a rubber 
mount 151 (See FIG. 2). 
The motor 20 includes an exhaust system. As disclosed above, exhaust is 
routed through a passage 90 from each cylinder 59 in a cylinder head 53, 
54 to a main exhaust passage 92. As best illustrated in FIG. 5, each 
exhaust passage 90 extending through the cylinder head 53, 54 from each 
combustion chamber 58 extends generally diagonally towards away from the 
watercraft and towards the valley between the cylinder banks 55, 57. 
An exhaust manifold 164 is connected to the engine 22. The manifold 164 has 
branch passages 92 which extend from a main passage 166. A branch passage 
92 extends from the main passage 166 to meet a corresponding one of the 
exhaust passages 90. The main exhaust passage 92 extends along the length 
of the engine 22 to the passage 124 (See FIG. 3) in the exhaust guide 122 
and thereafter through the remainder of the exhaust system. 
In this arrangement, the main gallery 142 of the lubricating system 
preferably extends vertically through the portion of the cylinder block 52 
positioned between the cylinder banks 55, 57 and between the coolant 
return passage 139. 
So arranged, the coolant jacket 133 surrounding the exhaust passage 92 is 
positioned on each side thereof, part of the jacket 133 formed within the 
cylinder block 52 and part within each cylinder head 53, 54. The cylinder 
cooling jackets 137 are positioned within the walls of the cylinder block 
52 adjacent the jacket 133, but defined separately therefrom. 
In accordance with the present invention, a drive arrangement is not only 
provided for engine accessories such as the alternator 148, but for the 
camshafts 84, 98. As best illustrated in FIG. 7, means are provided for 
driving the camshafts 84,98 off of the crankshaft 54. 
Preferably, means are provided for directly driving at least one camshaft 
of each bank 55,57 with the crankshaft 56. As illustrated, this means 
includes a toothed gear 168 (See FIG. 2) is mounted to a bottom portion of 
the crankshaft 56 near its connection to the top end 65 of the drive shaft 
60 and at a bottom end of the engine 22. A flexible transmitter, in the 
form of main timing chain 170, extends from the toothed gear or sprocket 
68 to a gear or sprocket 172 mounted on the intake camshaft 84 of one bank 
57, then around an idler 176 positioned within the engine 22 but between 
its banks 55,57, around a gear or sprocket 174 positioned on the exhaust 
camshaft 98 of the other bank 55, and then back to the sprocket 168 
mounted on the crankshaft 56. 
Several chain guides 178 are preferably provided along the travel path of 
the chain 170 for maintaining it in position. In addition, at least one 
chain tensioner 180 is provided for maintaining the chain taunt. In the 
embodiment illustrated, the tensioner 180 is connected to one of the 
guides 178 for pressing the guide 178 against the chain 170. 
Means also are provided for timingly driving the other camshaft of each 
bank 55, 57 which is not directly driven by the crankshaft 56. Preferably, 
a secondary chain 182 extends around the gear 172 mounted on the intake 
camshaft 84 of the first bank 57 to a gear positioned on the exhaust 
camshaft 98 of that bank. In this manner, rotation of the gear 172 on the 
intake camshaft 84 of this bank 57 effectuates synchronous rotation of the 
exhaust camshaft 98 of that bank as well. Again, a chain tensioner 186 is 
utilized to maintain the chain in taunt condition (See also FIG. 8). 
Another secondary chain 188 extends around the gear 174 positioned on the 
exhaust camshaft 98 of the other bank 55 and to a gear positioned on the 
intake camshaft 84 of that bank 55. The chain 188 is preferably maintained 
in taunt condition with a suitable chain tensioner 190. 
The sprockets or gears are preferably chosen so that the camshafts 84,98 
are rotated at a desired timing speed. 
FIGS. 9 and 10 illustrate a second drive arrangement in accordance with the 
present invention. In the description and illustrations of this 
embodiment, like reference numerals have been utilized to refer to like 
parts to those in the first embodiment, and an "a" designator has been 
added to all reference numerals of this embodiment. 
In this embodiment, the primary timing chain 170a extends around the 
toothed gear 172a mounted on the intake camshaft 84a of one bank 57a. The 
timing chain 170a then extends around an idler 176a, and then a gear 
positioned on the exhaust camshaft 98a of the other bank 57a. In this 
manner, one camshaft of each bank 55,57 is directly driven by the 
crankshaft 56a. 
Again, means are provided for driving the other camshaft of each bank 55, 
57. A gear 171a positioned above the toothed gear 172a on the intake 
camshaft 84a of the first bank 57a is arranged to be in driving engagement 
with a similar gear 173a mounted on the exhaust camshaft 98a of that bank 
57a (See FIG. 10). In this manner, rotation of the intake camshaft 84a of 
the bank 57a causes rotation of the exhaust camshaft 98a of that bank. 
Likewise, a gear 174a mounted on the exhaust camshaft 98a of the other bank 
55a is arranged in driving relation with a mating gear 175a positioned on 
the intake camshaft 84a of that bank 55a. So arranged, rotation of the 
exhaust camshaft 98a of that bank 55a causes synchronous rotation of the 
intake camshaft 84a of that bank. 
FIG. 11 illustrates a third embodiment drive arrangement in accordance with 
the present invention. In the description and illustration of this 
embodiment, like reference numerals have been utilized to refer to like 
parts to those in the embodiments above, and a "b" designator has been 
added to all reference numerals corresponding to this embodiment. 
In this embodiment, the primary timing chain 170b extends from the toothed 
gear positioned on the crankshaft 56b to a toothed gear 172b positioned on 
the exhaust camshaft 98b of the first bank 57b, and then around the idler 
176b and a gear on the exhaust camshaft 98b of the other bank 55b. Mating 
gears 171b, 173b and 174b, 175b are provided on the intake and exhaust 
camshafts 84b, 98b of each bank 55b, 57b for driving the intake camshafts 
84b in a manner similar to that described above. Thus, in this embodiment, 
the primary difference in the drive arrangement is that both exhaust 
camshafts 98b are directly driven by the timing chain 170b, instead of one 
intake and one exhaust camshaft as in the previous embodiment illustrated 
in FIGS. 9 and 10. 
FIGS. 12-17 illustrate a fourth drive arrangement in accordance with the 
present invention. In the description and illustrations of this 
embodiment, like reference numerals have been utilized to refer to like 
parts to those in the above embodiments, and a "c" designator has been 
added to all reference numerals. 
In this embodiment, the fuel system is illustrated as including a low 
pressure fuel pump 115c, fuel filter 117c and vapor separator 118c as 
described (but not illustrated) in conjunction with the first embodiment. 
As illustrated, these fuel system elements are positioned at the crankcase 
end of the engine 22c. 
The cooling system is arranged so that coolant flows first through the 
exhaust manifold cooling jacket 133c. A pressure relief valve 191c is 
preferably positioned along the coolant path after the coolant jacket 
133c. This pressure relief valve l91c is utilized to divert coolant 
through a relief passage 192c and thereon to the coolant drain system in 
the event the coolant pressure exceeds a predetermined high pressure. 
A thermostat 193c is positioned along the coolant path for monitoring the 
temperature oaf the coolant. A control valve is also positioned along the 
coolant path preferably before the coolant passes through the cylinder 
block and heads 52c, 53c, 54c of the engine 22c. The thermostat 193c is 
preferably positioned along the coolant path downstream of the passages 
135c, 137c through the cylinder block and heads 52c, 53c, 54c. The control 
valve is controlled by the thermostat 193c, such that if the coolant 
temperature is high, the valve is opened to allow coolant to flow through 
the engine 22c at a high rate. On the other hand, if the temperature of 
the coolant is low, then the valve is closed, allowing the engine to warm 
up. 
As in the previous embodiment, the coolant which is returned from the 
exhaust manifold cooling jacket 133c or from the engine 22c is split into 
paths A and B. A first amount of coolant is directed to a coolant pool 
139c surrounding an oil reservoir or pan 134c, and another pool 141c near 
the muffler 128c. When the liquid level in the pool 141c becomes too high, 
the cooling liquid runs over an overflow ledge or weir to a passage 
leading to a drain. The cooling liquid diverted to the drain is discharged 
from the motor. 
The remaining amount of coolant is directed around the exhaust pipe 126c 
for cooling it. This coolant then flows into the muffler 128c, where it is 
mixed with the exhaust gas. The coolant is carried with the exhaust gas 
through the propeller hub discharge back to the body of water. 
The drive arrangement of this fourth embodiment is illustrated in FIGS. 12, 
13 and 17. In this embodiment, the camshaft drive is positioned at the top 
end of the engine 22c. Here, a sprocket 168c is positioned on the 
crankshaft 56c just below the flywheel 104c near a top end of the 
crankshaft 56c. The timing chain 170c extends from the gear 168c to drive 
one or more of the camshafts 84c,98c in a manner similar to those of the 
embodiments described above. Preferably, the timing chain 170c is mounted 
within a space defined under a timing chain cover 109c. 
In addition, in this drive arrangement, the pulley 149c which is used to 
drive the generator 148c is positioned above the flywheel 104c on the top 
end of the crankshaft 56c. 
The drive arrangement of this embodiment is advantageous since the 
crankshaft 56c need not extend far beyond the end of the engine 22c to 
accommodate the flywheel 104c (since, as compared to the embodiment 
illustrated in FIG. 1, the crankshaft 56c need not extend far beyond the 
engine to accommodate the pulley 149c and then the flywheel 104c). Thus, 
the heavy flywheel 104c (which typically vibrates) is kept closer to the 
middle of the crankshaft 56c, reducing the fatigue on the crankshaft 56c 
and extending its life. 
Of course, the foregoing description is that of preferred embodiments of 
the invention, and various changes and modifications may be made without 
departing from the spirit and scope of the invention, as defined by the 
appended claims.