Harley Davidson Sportster Models 2009. Service Repair Manual - page 57

Table 3-10. Pistons-1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

0.239 mm

0.0094 in.

0.041-0.193 mm

0.0016-0.0076 in.

Oil control ring side
clearance

-

-

0.0013-0.0114 mm

0.00005-0.00045 in.

Piston pin fit (loose;
room temperature)

0.076 mm

0.0030 in.

0.038-0.066

0.0015-0.0026 in.

Piston fit in cylinder
(loose; room temper-
ature)

Table 3-11. Connecting Rods-883 cc/1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

0.0508 mm

0.00200 in.

0.0318-0.0445 mm

0.00125-0.00175 in.

Piston pin fit (loose)

0.762 mm

0.030 in.

0.013-0.64 mm

0.005-0.025 in.

Side play between fly-
wheels

0.0686 mm

0.0027 in.

0.010-0.043 mm

0.0004-0.0017 in.

Fit on crankpin

Table 3-12. Flywheels-883 cc/1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

0.254 mm

0.010 in.

0.00-0.254 mm

0.000-0.010 in.

Runout (flywheels at rim)

0.0508 mm

0.002 in.

0.00-0.0508 mm

0.000-0.002 in.

Runout (shaft at flywheel
end)

0.330 mm

0.013 in.

0.076-0.330 mm

0.003-0.013 in.

End play

Table 3-13. Pinion Shaft Bearing-883 cc/1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

31.735 mm

1.2494 in.

31.750-31.740 mm

1.2500-1.2496 in.

Pinion shaft journal dia-
meter

39.807 mm

1.5672 in.

39.741-39.756 mm

1.5646-1.5652 in.

Outer race diameter in
right crankcase

-

-

0.0030-0.0224 mm

0.00012-0.00088 in.

Bearing running clear-
ance

0.127 mm

0.0050 in.

0.058-0.109 mm

0.0023-0.0043 in.

Fit in cover bushing
(loose)

HOME

3-8  2009 Sportster Service: Engine

Table 3-14. Gearcase-883 cc/1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

0.0762 mm

0.003 in.

0.018-0.056 mm

0.0007-0.0022 in.

Cam gear shaft in
bushing (loose)

0.635 mm

0.025 in.

0.13-0.61 mm

0.005-0.024 in.

Cam gear shaft endplay
(except rear intake)
(min.)

1.016 mm

0.040 in.

0.15-0.61 mm

0.006-0.024 in.

Rear intake cam gear
shaft end play (min.)

Table 3-15. Oil Pump-883 cc/1200 cc

SERVICE WEAR LIMITS

NEW COMPONENTS

ITEM

0.102 mm

0.004 in.

0.08 mm

0.003 in.

Feed/scavenger
inner/outer gerotor clear-
ance

-

-

0.064 mm

0.0025 in.

Shaft to pump clearance

Table 3-16. Sprocket Shaft Bearing-883 cc/1200 cc

SPECIFICATION (INTERFERENCE FIT)

ITEM

0.152 mm

0.006 in.

Outer race fit in
crankcase (tight)

0.152 mm

0.006 in.

Inner race fit on
shaft (tight)

HOME

2009 Sportster Service: Engine  3-9

Table 3-17. Oil Pressure

PRESSURE

ENGINE

RPM

XR Models

XL Models

16-20 PSI (110.3-137.9

kPa)

7-12 PSI (43.3-82.7

kPa)

1000

40-44 PSI (275.8-303.4

kPa)

10-17 PSI (68.9-117

kPa)

2500

XL Models: Oil pressure at normal operating temperature
(pressure reading taken at oil pressure switch fitting)

XR Models: Oil pressure at normal operating temperature
(pressure reading taken at oil cooler inlet)

Table 3-18. Ignition System: 2009 Sportster XL Models

SPECIFICATION

COMPONENT

not adjustable

Ignition timing

12 volt, 12 amp/hr,

sealed and maintenance free

Battery

HD-6R12

Spark plug type

12 mm

Spark plug size

0.97-1.09 mm

0.038-0.043 in.

Spark plug gap

16.3-24.4 Nm

12-18 ft-lbs

Spark plug torque

Table 3-19. Ignition System: 2009 Sportster XR 1200 Model

SPECIFICATION

COMPONENT

not adjustable

Ignition timing

12 volt, 12 amp/hr,

sealed and maintenance free

Battery

10R12X

Spark plug type

12 mm

Spark plug size

0.81-0.97 mm

0.032-0.038 in.

Spark plug gap

16.3-24.4 Nm

12-18 ft-lbs

Spark plug torque

HOME

3-10  2009 Sportster Service: Engine

3.3

ENGINE

GENERAL

The engine is a two-cylinder, four-cycle, air-cooled, overhead-
valve V-twin. It has three major component assemblies: cyl-
inder, crankcase, and gear case.

The cylinder assembly includes cylinder head, valves, rocker
arm cover, rocker arms, and piston. Cylinders mount on the
crankcase in a 45 degree "V", with both connecting rods con-
nected to a single crank pin.

The up-and-down motion of the piston in the cylinder is con-
verted to circular motion in the crankcase. The multi-piece
crankshaft consists of a crank pin mounted between two
counterweighted flywheels, which rotate on two end shaft
bearings. The lower end of the rear cylinder connecting rod is
forked to fit around the single-end front cylinder connecting
rod, allowing a single connecting rod crank pin connection to
the flywheel.

The gear case is located on the right side of the crankcase.
The gear case houses the gear train which operates and times
the valves and ignition. The cam gear train, consisting of four
cam shafts with one cam lobe on each shaft, is gear driven.
The engine valves are opened and closed through the mech-
anical linkage of tappets, push rods, and rocker arms. Hydraulic
lifters, located in the tappets, automatically compensate for
heat expansion to maintain the no-lash fit of valve train com-
ponents. Tappets serve to transmit the cam action to the valve

linkage. Valve timing is obtained by aligning timing marks when
installing cam gears.

Ignition spark is produced by the operation of a microprocessor-
controlled Electronic Control Module (ECM), ignition coil, and
spark plugs. Spark timing is determined primarily by crankshaft
rotation, triggering a magnetic sensing unit.

Each spark plug fires independently at the end of that cylinder's
compression stroke, igniting the air/fuel mixture in the cylinder.

The engine has a force-feed (pressure) type oiling system,
incorporating oil feed and return pumps in one pump body,
with one check valve on the oil feed side. The feed pump forces
oil to the engine, lubricating lower connecting rod bearings,
rocker arm bushings, valve stems, valve springs, push rods,
and tappets. Cylinder walls, pistons, piston pins, timing gears
and bushings, and main bearings are lubricated by oil spray
thrown off connecting rods and crankshaft, and by oil draining
from each rocker box through an internal drain passage in each
cylinder and each tappet guide. Piston jets spray oil on the
underside of the pistons to cool the piston crown and skirt area.

A small amount of oil is sprayed through an oil galley jet onto
the rear intake cam gear in the gear case; oil is transferred to
the teeth of all the cam gears by way of the gear meshing
action. The oil-scavenging section of the pump returns oil to
the tank from the engine. See 

3.8 ENGINE LUBRICATION

SYSTEM

 later in this section for further information.

HOME

2009 Sportster Service: Engine  3-11

3.4

OIL PRESSURE

GENERAL

XL Models: The oil pump is non regulatory and delivers its
entire volume of oil under pressure to the oil filter mount.

XR Models: The feed oil pump incorporates a bypass valve
that will open at approximately 50 psi (345 kPa), preventing
overpressure in the oil cooler and related components. The
XR Models also incorporate a thermostat in the oil cooler return
path, and can have an effect on measured oil pressure.

When an engine is cold, the engine oil will be more viscous
(i.e., thicker). During start-up of a cold engine, oil pressure will
be higher than normal and oil circulation will be somewhat
restricted within the oiling system. As the engine warms to
normal operating temperature, the engine oil will warm up and
become less viscous; oil pressure decreases.

When an engine is operated at high speeds, the pump rotors
rotate faster, increasing the volume of oil circulated through
the oiling system, resulting in higher oil pressure. As engine
speed is reduced, the volume of oil pumped is also reduced,
resulting in lower oil pressure.

Oil Pressure Indicator Lamp

See 

Figure 3-1

. The red OIL PRESSURE indicator lamp illu-

minates to indicate improper circulation of the engine oil.

Refer to 

Table 3-20

. The oil pressure indicator lamp turns ON

when:

•

Ignition switch is turned on prior to starting engine.

•

Oil is not circulating through the running engine.

•

Oil pressure is abnormally low on the running engine.

•

Engine is idling far below 1000 RPM.

The oil pressure indicator lamp turns OFF when oil is circulating
with adequate pressure through the engine running at 1000
RPM or greater.

sm02321

Figure 3-1. Oil Pressure Indicator Lamp

If the oil pressure indicator lamp remains lit, always check
the oil supply first. If the oil supply is normal and the lamp
is still lit, stop the engine at once and do not ride further
until the trouble is located and the necessary repairs are
made. Failure to do so may result in engine damage.
(00157a)

NOTE

If the ignition is turned back on immediately after the engine
is stopped, the oil pressure indicator lamp may not turn on right
away because of oil pressure retained in the filter housing.

Table 3-20. Oil Lamp Troubleshooting

PROBABLE CAUSES

OIL PRESSURE INDICATOR LAMP

•

Empty oil tank.

•

Clogged feed line (ice and sludge, freezing temperatures).

•

Air-bound oil line.

•

Grounded oil pressure switch wire.

•

Malfunctioning oil pressure switch.

•

Diluted oil.

•

Malfunctioning check valve.
See 

3.26 OIL FILTER MOUNT

 and 

3.14 PRECISION COOLING SYSTEM: XR

MODELS, Cylinder Head Oil Feed Assembly

•

Malfunctioning or improperly installed pressure relief valve.

Stays on at speeds above idle.

•

Incorrect idle speed. Malfunctioning or improperly installed check valve.
See 

3.26 OIL FILTER MOUNT

 and 

3.14 PRECISION COOLING SYSTEM: XR

MODELS, Cylinder Head Oil Feed Assembly

•

Malfunctioning or improperly installed pressure relief valve.

Flickers at idle.

•

Malfunctioning signal switch.

•

Malfunction in wiring.

•

Burned-out signal bulb.

•

Dead battery.

•

See NOTE before this table.

Does not glow when ignition is turned on
(prior to operating engine).

HOME

3-12  2009 Sportster Service: Engine

CHECKING OIL PRESSURE

TOOL NAME

PART NUMBER

OIL PRESSURE SENDING UNIT
WRENCH

HD-48386

OIL PRESSURE GAUGE ADAPTER

HD-96921-125

OIL PRESSURE TEST GAUGE KIT

HD-96921-52D

OIL PRESSURE GAUGE ADAPTER

HD-96925-58

Check operating oil pressure as follows:

1.

Fill oil tank to proper level. See 

1.6 ENGINE OIL AND

FILTER

.

2.

Place a container under vehicle to catch any oil that may
leak out.

3.

Obtain OIL PRESSURE TEST GAUGE KIT (Part No. HD-
96921-52D).

Connecting Gauge: XL Models

1.

Remove voltage regulator DC output connector and neutral
switch wiring harness from voltage regulator caddy.
Remove caddy. See 

6.32 MAIN WIRING HARNESS

.

2.

See 

Figure 3-2

. Unplug connector [120] (3) from oil pres-

sure indicator lamp switch (2) located under oil filter (1)
by pulling elbow connector straight down from stud on oil
pressure switch.

3.

Using OIL PRESSURE SENDING UNIT WRENCH (Part
No. HD-48386), remove oil pressure switch.

4.

See 

Figure 3-3

. Install OIL PRESSURE GAUGE

ADAPTER (Part No. HD-96925-58) (2) in oil pressure
indicator lamp switch mounting hole. Tighten adapter
snugly. DO NOT OVERTIGHTEN.

Connecting Gauge: XR Models

1.

See 

Figure 3-5

. Disconnect the quick connect fitting from

the inlet side of the oil cooler (4). See 

3.14 PRECISION

COOLING SYSTEM: XR MODELS, General

.

2.

Connect OIL PRESSURE GAUGE ADAPTER (Part
No. HD-96921-125) (5) to the oil hose (6).

3.

Connect the other end of the adapter to the oil cooler fitting
(4).

Testing Pressure

1.

See 

Figure 3-4

 or 

Figure 3-5

. Assemble banjo bolt (2),

washer (3), OIL PRESSURE GAUGE banjo fitting (1) and
second washer onto adapter and tighten snugly.

NOTE

For an accurate reading, engine oil should be at normal oper-
ating temperature: 230°F (110°C).

2.

Temporarily secure oil pressure gauge and hose to
motorcycle frame with cable straps. Make sure gauge and
hose assembly do not interfere with normal operation of
the vehicle. Start engine and ride motorcycle at least 20
miles (32 km) at or above 50 mph (80 km/h) to allow
engine to reach operating temperature.

3.

Check and record the pressure readings at normal idle
(approximately 1000 RPM) and again at 2500 RPM.

Compare the readings with the specifications in

Table 3-21

.

Table 3-21. Oil Pressure

PRESSURE

ENGINE

RPM

XR Models

XL Models

16-20 PSI (110.3-137.9

kPa)

7-12 PSI (43.3-82.7

kPa)

1000

40-44 PSI (275.8-303.4

kPa)

10-17 PSI (68.9-117

kPa)

2500

XL Models: Oil pressure at normal operating temperature
(pressure reading taken at oil pressure switch fitting)

XR Models: Oil pressure at normal operating temperature
(pressure reading taken at oil cooler inlet)

Removing Gauge: XL Models

1.

Stop engine. Remove OIL PRESSURE GAUGE assembly
from oil pressure indicator lamp switch mounting hole in
crankcase. Cut cable straps securing gauge and hose.
Remove banjo bolt, gauge assembly, washers and adapter
from vehicle.

2.

See 

Figure 3-2

. Coat threads of oil pressure switch (2)

with LOCTITE 565 HIGH PERFORMANCE PIPE
SEALANT with TEFLON. Reinstall oil pressure switch.
Using OIL PRESSURE SENDING UNIT WRENCH, tighten
switch snugly. DO NOT OVERTIGHTEN.

3.

Plug in connector [120] (3) by pushing elbow connector
straight up onto stud on oil pressure switch.

4.

Install voltage regulator caddy and attach DC output con-
nector and neutral switch wiring harness to caddy. See

6.32 MAIN WIRING HARNESS

.

Removing Gauge: XR Models

1.

Stop engine. Cut cable straps securing gauge and hose.
Remove banjo bolt, gauge assembly, washers and adapter
from vehicle.

2.

Connect oil hose to oil cooler fitting, making sure it is
securely latched.

Finalize Test

NOTE

If an appreciable amount of oil leaked out when oil pressure
switch was removed, it will have to be replaced with fresh oil.

1.

Check oil level in oil tank. See 

1.6 ENGINE OIL AND

FILTER

. Top off oil level if necessary.

2.

Start engine and test oil pressure switch for proper opera-
tion. Check for oil leaks.

HOME

2009 Sportster Service: Engine  3-13

1

3

2

sm01478

1.

Oil filter

2.

Oil pressure indicator lamp switch

3.

Oil pressure switch connector [120]

Figure 3-2. Oil Pressure Indicator Lamp Switch

5

4

3

2

1

sm00215

1.

Gauge

2.

Adapter, pressure switch hole (XL models)

3.

Adapter, oil cooler line (XR models)

4.

Banjo bolt

5.

Washers (2)

Figure 3-3. Oil Pressure Test Gauge Set

1

5

2

4

3

sm01479

1.

Oil pressure gauge banjo fitting

2.

Banjo bolt

3.

Washer (2)

4.

Adapter

5.

Oil pressure gauge hose

Figure 3-4. Oil Pressure Test Connections: XL Models

3

4

2

1

6

5

sm05383

1.

Oil pressure gauge banjo fitting

2.

Banjo bolt

3.

Washer (2)

4.

Oil cooler connector

5.

Adapter

6.

Oil cooler hose fitting

Figure 3-5. Oil Pressure Test Connections: XR Models

HOME

3-14  2009 Sportster Service: Engine

3.5

CRANKCASE BREATHING SYSTEM: XL
MODELS

GENERAL

See 

Figure 3-6

. On the piston downstroke, a mixture of crank-

case air and oil mist is vented up the push rod covers (1)
through a breather valve (2) in each inner rocker box section.

The oil mist separates from the crankcase air, collects and
passes through a small drain hole adjacent to the exhaust valve
in the head where it eventually returns to the crankcase.

The crankcase air is routed through a passage in each cylinder
head. The crankcase air then travels through each air cleaner
backing plate mounting bolt (3) into the filtered side of the air
cleaner.

2

3

1

sm03427

1.

Push rod cover (2)

2.

Breather valve

3.

Bolt, air cleaner backing plate mounting

Figure 3-6. Crankcase Breathing System: XL Models

HOME

2009 Sportster Service: Engine  3-15

3.6

CRANKCASE BREATHING SYSTEM: XR
MODELS

GENERAL

During engine operation, internal crankcase pressure increases
due to the reciprocating components and also any combustion
gas that passes by the piston rings. Along with increased
pressures, a mixture of air and oil mist develops in the crank-
case. The Crankcase Breathing System will vent the pressure
and separate the air from the oil. The following description is
for one cylinder however, each cylinder is equipped the same.

See 

Figure 3-7

. During the piston downstroke, internal crank-

case pressure increases, forcing a vapor (9) of crankcase air
and oil mist into the area around the rocker arms and valve
springs. The vapor travels down through two passages (6) in
the inner rocker cover into a cavity (7) between the cylinder
head and inner rocker cover. The vapor then moves into the
filter media (8) of the breather valve (3).

As the oil-laden vapor passes through the filter media (8) of
the breather valve assembly, the oil mist separates from the
crankcase air, drains back into cavity (7) where it flows toward
the exhaust valve area. The oil then passes through a small
drain hole adjacent to the exhaust valve in the head where it
eventually returns to the crankcase.

The air pressure forces the umbrella valve (5) of the breather
valve to open and air is routed through a fitting (4) in the outer
rocker cover. The umbrella valve prevents the air from moving
back into the crankcase during piston upstroke. The crankcase
air then travels through a vapor hose (2) which is connected
to a hose and tee assembly (10) in the airbox. The air eventu-
ally exits into the intake air stream above the induction module
and is consumed by the engine.

HOME

3-16  2009 Sportster Service: Engine

4

10

5

8

6

3

7

9

9

1

2

sm05376

1.

Rocker cover

2.

Vapor hose

3.

Breather valve assembly

4.

Vapor hose fitting

5.

Umbrella valve

6.

Passage (2)

7.

Cavity

8.

Filter media

9.

Vapor from crankcase

10. Hose and tee assembly

Figure 3-7. Crankcase Breathing System: XR Models

HOME

2009 Sportster Service: Engine  3-17

3.7

TROUBLESHOOTING

DIAGNOSING VALVE TRAIN NOISE

To diagnose and correct noisy hydraulic lifters and valve train
components, use the following procedures:

1.

With engine and oil at normal operating temperature, check
oil pressure at 2000 RPM. If oil pressure is above 50 PSI
(345 kN/m

2

) or below 5 PSI (34 kN/m

2

), inspect oil pump,

crankcase passages and oil hoses for restrictions or
blockage. Repair or replace parts as necessary.

2.

If oil is reaching the hydraulic lifters, remove and inspect.
See 

3.19 VALVE TAPPETS

. Clean lifter bore of all foreign

material. Replace hydraulic lifter if required.

3.

Examine pushrod, lifter and lifter block for proper fit and
any signs of unusual wear. Replace parts as necessary.

4.

Visually inspect camshaft lobes for abnormal wear.

5.

Remove camshafts and pinion gear, clean and inspect for
wear and fit. Replace parts as necessary.

6.

Remove cylinder head and rocker box assemblies. Check
rocker arm end play and check for binding. Inspect valve
stems for scuffing and check stem to guide clearance.
Check valve seats for signs of looseness or shifting.

7.

Reface valves and valve seats.

COMPRESSION TEST

TOOL NAME

PART NUMBER

CYLINDER COMPRESSION GAUGE

HD-33223-1

Satisfactory engine performance depends upon a mechanically
sound engine. In many cases, unsatisfactory performance is
caused by combustion chamber leakage. A compression test
can help determine the source of cylinder leakage.

A proper compression test should be performed with the engine
at normal operating temperature when possible.

1.

Disconnect spark plug wires. Clean around spark plug
base and remove spark plugs.

2.

Connect CYLINDER COMPRESSION GAUGE (Part
No. HD-33223-1) to front cylinder per manufacturer's
instructions.

3.

Make sure transmission is in neutral. With throttle plate in
wide open position, crank engine continuously through 5
to 7 full compression strokes.

4.

Note gauge readings at the end of the first and last com-
pression strokes. Record test results.

5.

Connect CYLINDER COMPRESSION GAUGE to rear
cylinder and repeat Steps 3 and 4.

a.

Compression is normal if final readings are within the
range specified in 

Table 3-22

, and do not indicate

more than a 10 psi (0.689 Bar) variance between
cylinders.

b.

If compression is below 100 psi (6.89 Bar) for 883 cc
engines or 150 psi (10.3 Bar) for 1200 cc engines,
refer to 

Table 3-23

.

6.

Inject approximately 1/2 oz. (15 ml) SAE 30 engine oil into
each cylinder and repeat the compression tests on both
cylinders. Readings that are considerably higher during
the second test indicate worn piston rings.

NOTE

After completing the compression test(s) and reinstalling the
spark plugs, make sure the throttle plate is in the closed posi-
tion before starting the engine.

Table 3-22. Normal Compression Ranges

COMPRESSION

ENGINE

BAR

PSI

11.4-12.4

165-180

XL883 cc

13.8-15.5

200-225

XL1200 cc

11.7-12.8

170-185

XR1200 cc

Table 3-23. Compression Test Results

TEST RESULTS

DIAGNOSIS

Compression low on first stroke, tends to build
up on the following strokes, but does not reach
normal. Improves considerably when oil is
added to cylinder.

Ring trouble

Compression low on first stroke, does not build
up much on following strokes. Does not
improve considerably with the addition of oil.
Check for correct pushrod length.

Valve trouble

Same reaction as valve trouble.

Head gasket
leak

CYLINDER LEAKAGE TEST

TOOL NAME

PART NUMBER

CYLINDER LEAKDOWN TESTER

HD-35667-A

The cylinder leakage test pinpoints engine problems including
leaking valves, worn, broken or stuck piston rings and blown
head gaskets. The cylinder leakage tester applies compressed
air to the cylinder at a controlled pressure and volume and
measures the percent of leakage from the cylinder.

Use CYLINDER LEAKDOWN TESTER (Part No. HD-35667-
A) and follow the specific instructions supplied with the tester.

The following are some general instructions that apply to
Harley-Davidson V-twin engines:

1.

Run engine until it reaches normal operating temperature.

2.

Stop engine. Clean dirt from around spark plugs and
remove the spark plugs.

3.

Remove the air cleaner and set the throttle in the wide
open position.

4.

The piston in the cylinder being tested must be at top dead
center of compression stroke (both valves closed) during
the test.

HOME

3-18  2009 Sportster Service: Engine

5.

To keep the engine from turning over when air pressure
is applied to the cylinder, engage transmission in fifth gear
and lock the rear brake.

NOTE

Before performing the cylinder leakage test, verify that the
tester itself is free from leakage to obtain the most accurate
test results. With a soap solution [applied around all tester fit-
tings], connect the cylinder leakdown tester to the compressed
air source and look for any bubbles that would indicate leakage
from the tester.

6.

Following the manufacturer's instructions, perform a cyl-
inder leakage test on the front cylinder. Make a note of
the percent of leakage. Leakage greater than 12% indic-
ates internal engine problems.

7.

Listen for air leaks at induction module intake, exhaust
pipe and head gasket. Air escaping through the induction
module indicates a leaking intake valve. Air escaping
through the exhaust pipe indicates a leaking exhaust valve.

NOTE

If air is escaping through valves, check push rod length.

8.

Repeat procedure on rear cylinder.

NOTE

After completing the cylinder leakage test(s) and reinstalling
the spark plugs, make sure the throttle plate is in the closed
position before starting the engine.

DIAGNOSING SMOKING ENGINE OR HIGH
OIL CONSUMPTION

Perform 

3.7 TROUBLESHOOTING, Compression Test

 or

3.7 TROUBLESHOOTING, Cylinder Leakage Test

 as described

previously. If further testing is needed, remove suspect head(s)
and inspect for the following:

Check Prior to Cylinder Head Removal

1.

Oil tank overfilled.

2.

Oil carryover.

3.

Breather hose restricted.

4.

Restricted oil filter.

Check After Cylinder Head Removal

1.

Oil return passages for clogging.

2.

Valve guide seals.

3.

Valve guide to valve stem clearance.

4.

Gasket surface of both head and cylinder.

5.

Cylinder head casting's porosity allowing oil to drain into
combustion chamber.

6.

O-ring damaged or missing from oil pump/crankcase
junction.

ADJUSTMENT AND TESTING

General

When an engine needs repair, it is not always possible to
determine definitely beforehand whether repair is possible with
only cylinder heads, cylinders, and pistons disassembled, or
whether complete engine disassembly is required for crankcase
repair.

Most commonly, only cylinder head and cylinder repair is
needed (valves, rings, piston, etc.), and it is recommended
procedure to service these units first, allowing engine crankcase
to remain in frame.

Follow the procedure outlined in 

3.15 TOP END OVERHAUL:

DISASSEMBLY, Stripping Motorcycle for Top End Repair

, to

strip motorcycle for removal of cylinder heads, cylinders, and
pistons.

After disassembling "upper end" only, it may be found that
crankcase repair is necessary; this requires removal of engine
crankcase from chassis outlined in 

3.12 REMOVING ENGINE

FROM CHASSIS

.

NOTE

If engine is removed from chassis, do not lay engine on primary
side. Laying engine on primary side will damage the clutch
cable end fitting. If fitting is damaged, clutch cable must be
replaced.

Symptoms indicating a need for engine repair are often mis-
leading; but generally, if more than one symptom is present,
possible causes can be narrowed down to make at least a
partial diagnosis. An above-normal consumption of oil, for
example, could be caused by several mechanical faults. See

1.35 TROUBLESHOOTING

. However, when accompanied by

blue-gray exhaust smoke and low engine compression, it
indicates the piston rings need replacing. Low compression by
itself, however, may indicate improperly seated valves, in
addition to or in lieu of worn piston rings.

Piston slap is a condition where piston and/or cylinder are worn
out-of-round and are loose fitting, allowing the piston to slap
from front to rear of the cylinder as it moves up and down.

Most frequently, valves, rings, pins, bushings, and bearings
need attention at about the same time. If the possible causes
can be narrowed down through the process of elimination to
indicate any one of the above components is worn, it is best
to give attention to all of the cylinder head and cylinder parts.

HOME

2009 Sportster Service: Engine  3-19

3.8

ENGINE LUBRICATION SYSTEM

OIL PUMP OPERATION

See 

Figure 3-8

 or 

Figure 3-9

. The oil pump consists of two

gerotor gear sets, feed and scavenge (return), housed in one
pump body. The feed pump distributes oil to the engine and
has fewer lobes than the scavenge pump, allowing for greater
pressure development. The scavenge pump returns oil to the

tank and has more lobes than the feed pump allowing for
greater oil flow.

XL Models: Both rotor sets are driven off a common shaft that
is coupled by gears to the crankshaft.

XR Models: The feed rotor set is driven by flats on the front
intake camshaft. The scavenge rotor set is driven by flats on
the rear exhaust camshaft.

15

14

12

13

11

9

10

7

4

2

3

1

5

8

6

sm03426

9.

1.

Retaining ring

Cover, oil pump

2.

10.

Screw, w/ washer (2)

Washer, thrust

11.

3.

O-ring

Screw, Torx (2)

4.

12.

Connector

Body, oil pump

13.

5.

Elbow fitting

Hose fitting

6.

14.

Gerotor assy, feed

Gear shaft

15.

7.

Gasket

Gerotor separator plate

8.

Gerotor assy, scavenge

Figure 3-8. Oil Pump: XL Models

HOME

3-20  2009 Sportster Service: Engine

5

4

1

3

2

sm05375

4.

1.

Feed rotor set

Housing, oil pump

2.

5.

Exhaust camshaft, rear cylinder

Scavenge rotor set

3.

Intake camshaft, front cylinder

Figure 3-9. Oil Pump: XR Models

Each gerotor-type gear set has two parts; an inner and an outer
gerotor. The inner gerotor has one less lobe than the outer

gerotor. Both gerotors have fixed centers which are offset to
each other.

HOME

2009 Sportster Service: Engine  3-21

See 

Figure 3-10

. As the crankshaft rotates, the cavity between

the inner and outer gerotors on the inlet side of the pump
increases in volume. This creates a vacuum causing oil to be
drawn in. The cavity continues to increase until the volume is
equivalent to that of the missing lobe on the inner gerotor. Note
that the inlet and outlet sides of the pump are sealed by the
tips and lobes of the inner and outer gerotors.

See 

Figure 3-11

. Continued rotation moves the pocket of oil

to the outlet side of the pump. In this area, the cavity decreases
in volume as the gerotor lobes mesh causing the oil to be
squeezed out the discharge port. As the cavity on the outlet
side is emptied, a second seal formed by the tips and lobes of
the inner and outer gerotors prevents oil on the outlet side (high
pressure) from being transferred to the inlet side (low pressure).
In operation, the gerotors provide a continuous flow of oil.

1

4

3

2

sm02317

1.

Oil in

2.

Seal

3.

Outer gerotor

4.

Inner gerotor

Figure 3-10. Inlet Side Oil Flow

2

3

1

sm02319

1.

Seal

2.

Oil out

3.

Continuous flow

Figure 3-11. Outlet Side Oil Flow

HOME

3-22  2009 Sportster Service: Engine

OIL FLOW: XL MODELS

NOTE

The following paragraph numbers correspond with the
numbered callouts in the 

Figure 3-12

 foldout.

1.

Oil is gravity-fed from the oil tank to the gerotor-style oil
pump through a feed hose. Oil enters the feed section
and fills a cavity located under the feed pump.

NOTE

See 

3.24 OIL PUMP: XL MODELS

 for a complete explanation

of the gerotor pump.

2.

The feed pump transfers oil from the inlet cavity through
the feed hose to the oil filter mount.

3.

Oil flows through the filter mount cavity to the oil filter.

4.

Oil enters the peripheral cavity of the oil filter, passes
through the filtering medium into the central cavity of the
oil filter, and flows into the filter adapter (fitting which
connects filter to filter mount).

5.

Adequate oil pressure in the filter mount cavity activates
the oil pressure indicator lamp switch and shuts off the
oil pressure indicator lamp.

6.

Oil flowing from the filter adapter opens the check ball.
The check ball opens at 10-13 psi (69-90 kPa) oil pressure.

7.

With the check ball open, oil flows into the crankcase
feed galley.

8.

Oil flows through the feed galley in the crankcase to the
tappet blocks and hydraulic lifters. Cross-drilled pas-
sages intersect the main feed galley and carry oil to each
hydraulic lifter. From this cavity, oil is also fed to the piston
jets.

9.

Oil also enters an intersecting passage in the gearcase
cover. Oil flow is then routed to the crankshaft area.

10. Oil enters a hole in the end of the pinion gear shaft and

travels to the right flywheel where it is routed through the
flywheel to the crank pin. Oil is forced through the crank
pin to properly lubricate the rod bearing assembly.

11. Oil flows up passages in the push rods to the rocker arm

shafts and bushings.

12. The valve stems are lubricated by oil supplied through

drilled oil holes in the rocker arms.

13. Oil collected in the push rod areas of the cylinder heads

flows down the push rod covers, through drain holes in
the tappet blocks and into the gearcase. After providing
lubrication to the gearcase components the oil flows to
the return side of the oil pump.

14. Feed oil to the rocker area is returned to the gearcase

through a passage in the head, cylinder, and crankcase.

15. Oil collected in the sump is splash-fed to the pistons, cyl-

inder walls and flywheel components.

16. Oil collected in the sump area returns to the scavenge

section of the oil pump through a passage located in the
rear section of the sump. Oil flow to the pump is accom-
plished by the scavenging effect of the pump and by the
pressure created by the downward stroke of the pistons.

17. Return oil fills a cavity above the pump's return gears.

The return gears pump oil back to the oil tank.

18. A small amount of oil flows from the feed galley in the right

crankcase through a restricted orifice, which sprays the
oil onto the rear intake cam gear in the gearcase. Oil is
transferred to the teeth of all the cam gears through the
gear meshing action.

OIL FLOW: XR MODELS

NOTE

The following paragraph numbers correspond with the
numbered callouts in the 

Figure 3-13

 foldout.

1.

Oil is gravity-fed from the oil tank to the gerotor-style oil
pump through a feed hose and internal passages. Oil
enters the inlet cavity of the feed pump.

NOTE

See 

3.25 OIL PUMP: XR MODELS

 for a complete explanation

of the gerotor pump.

2.

The feed pump transfers oil through a passage in the
pump housing to a point where it splits direction. The pump
is capable of delivering more oil than can flow through the
engine. When oil pressure exceeds approximately 50 psi
(345 kPa), the bypass valve will open allowing oil to cir-
culate back into the inlet side of the feed pump.

3.

Part of the oil passes through an internal passage toward
the oil filter and part heads toward the oil cooler line.

4.

Oil flowing toward the oil cooler exits the oil pump housing
through a line that is connected via a quick connect fitting
at each end, and enters the lower end of the oil cooler. Oil
flows up through the oil cooler and exits the upper end
where it flows back to the oil pump housing.

5.

A thermostat is located where the oil cooler return line
connects to the oil pump housing. No oil from the oil cooler
will flow past the thermostat until the engine oil temper-
ature reaches 190°F (88°C). Once the thermostat begins
to open, oil from the oil cooler flows past it while oil flow
directly from the feed pump is restricted, providing cooled
oil for engine lubrication. When the thermostat reaches
full open position, a seal on the end seals off oil flow dir-
ectly from the pump and all oils passes through the oil
cooler, past the thermostat, and towards the oil filter.

6.

Oil flowing to the filter passes through an internal passage
to the oil filter mount.

7.

Oil flows through the filter mount cavity to the oil filter.

8.

Oil enters the peripheral cavity of the oil filter, passes
through the filtering medium into the central cavity of the
oil filter, and flows into the filter adapter (fitting which
attaches the filter to filter mount).

9.

Adequate oil pressure in the filter supply passage activates
the oil pressure indicator lamp switch and shuts off the
oil pressure indicator lamp.

10. Oil flowing from the filter adapter opens the check ball.

The check ball opens at 5-7 psi (34-48 kPa) oil pressure.

11. With the check ball open, oil flows into the crankcase

feed galley.

HOME

2009 Sportster Service: Engine  3-23