Snowmobile Polaris EDGE / WIDETRAK (2007-2012 year). Manual - part 23

 

  Index      Snowmobiles / ATV     LX Snowmobile Polaris EDGE / WIDETRAK - service manual 2007-2012 year

 

Search            

 

 

 

 

 

 

 

  

 

Content   ..  21  22  23  24   ..

 

 

Snowmobile Polaris EDGE / WIDETRAK (2007-2012 year). Manual - part 23

 

 

4.6

Fuel System

9923396 - 2007-2012 EDGE/Widetrak LX Service Manual

©2011 Polaris Sales Inc.

selecting the proper main jet always use the lowest
elevation and temperature that is likely to be
encountered.

Piston / Throttle Valve

The throttle valve controls the rate of engine air intake by
moving up and down inside the main bore. At small throttle
openings, air flow control is performed chiefly by the
cutaway. By controlling air flow the negative pressure over
the needle valve is regulated, in turn varying the fuel flow.

The throttle valves are numbered 1.0, 1.5, 2.0, etc.,
according to the size of the cutaway in millimeters. The
higher the number, the leaner the gasoline/air mixture.

Jet Needle/Needle Jet

The jet needle and needle jet have the most effect
between 3/8 and 3/4 throttle opening. Some mixture
adjustment can be accomplished by changing the location
of the “E” clip on the needle. Moving the clip down raises
the needle in the jet passage and enriches the mixture.
Moving the clip up lowers the needle in the jet passage
and leans the mixture. Letter and number codes are
stamped into the needle and the jet indicating sizes and
tapers (taper of needles only) of each.

Jet Needle

The jet needle tapers off at one end and the clearance
between the jet needle and the needle jet increases as the
throttle valve opening gets wider. The air/fuel mixture ratio
is controlled by the height of the “E” ring inserted into one
of the five slots provided in the head of the jet needle.

Needle Jet

The needle jet works in conjunction with the jet needle. 

CAUTION

A main jet that is too small will cause a lean operation 
condition and may cause serious engine damage. Jet 
the carburetors carefully for elevation and temperature 
according to the jetting charts in the Specifications 
Chapter of this manual or the models’ Owner’s Manual 
Supplements.

INTAKE SIDE

4.7

Fuel System

4

9923396 - 2007-2012 EDGE/Widetrak LX Service Manual

©2011 Polaris Sales Inc.

VM CARBURETOR DISASSEMBLY / 
INSPECTION / ASSEMBLY

VM Carburetor Disassembly

1.

Remove the throttle slide cap, spring, and throttle
slide. Extract the retainer to remove the needle and
throttle cable plug.

2.

Remove the choke plunger. Inspect the plunger for
wear and replace if required. Inspect the plunger seat
for damage or foreign material.

3.

Check the choke plunger and cable movement.
Plunger must move up and down in bore without
binding.

4.

Remove the float bowl. Inspect the choke fuel supply
passage.

5.

Remove the float pin, then remove the inlet needle
and seat assembly.

6.

Inspect the needle tip for abnormal wear and tear.
Replace if required.

4.8

Fuel System

9923396 - 2007-2012 EDGE/Widetrak LX Service Manual

©2011 Polaris Sales Inc.

7.

Remove the pilot and main jets.

8.

Thoroughly clean the carburetor body with carburetor
cleaner. Blow dry with compressed air. Verify all air,
fuel, and choke passages are clean.

9.

Assembly is the reverse of disassembly.

Float Arm Adjustment

Proper float arm adjustment in critical to carburetor
performance.

1.

Invert carburetor assembly.

2.

Carefully bend the float arm tang contacting the inlet
needle so the float arm legs are parallel with the float
bowl mating surface.

Needle and Seat Leak Testing

A leaking needle and seat can cause hard starting and
poor runability issues.

1.

Invert the carburetor assembly. Verify the float arm is
properly adjusted.

2.

Attach a Mity Vac pressure pump to the fuel inlet
fitting. 

3.

Apply approximately 5 PSI of pressure and wait for at
least one minute. The needle and seat should hold the
pressure indefinitely. If the pressure drops rapidly,
replace the needle and seat assembly.

CAUTION

Always wear eye protection when using compressed air.

4.9

Fuel System

4

9923396 - 2007-2012 EDGE/Widetrak LX Service Manual

©2011 Polaris Sales Inc.

MIKUNI TM CARBURETOR

Disassembly

1.

Remove the carburetor from the engine before
disassembling. Clean the outside of the carburetor
thoroughly with solvent. Do not use compressed air to
dry at this time.

2.

Remove all top cap screws (1), top cap (2) and gasket
(3).

3.

Locate the arm screw (4) and loosen it just enough to
move the arm (5) out of the way so that you can
remove the needle (6) e-clip and the plastic washer
from the throttle slide.

NOTE:  Keep track of the plastic washer (9), and place
it so it is on the top of the throttle valve when installing
the needle and e-ring back into the carburetor.

4.

Inspect the needle (7), e-clip (8), and plastic washer
(9) for wear.

5.

Remove the four screws (10) on the funnel face.

6.

Turn throttle shaft so the throttle slide (11) slides open
all the way. 

7.

With slide fully open, pull funnel (12) out from the
bottom first. Inspect the gasket (13).

8.

Check for wear on the faces of the slides.

CAUTION

W

EAR

 

EYE

 

PROTECTION

 

WHEN

 

USING

 

COMPRESSED

 

AIR

 

OR

 

WHEN

 

USING

 

CLEANING

 

SOLVENTS

. R

EVIEW

 

ALL

 

FUEL

 

SYSTEM

 

WARNINGS

 

LOCATED

 

AT

 

THE

 

BEGINNING

 

OF

 

THIS

 

CHAPTER

 

BEFORE

 

PROCEEDING

.

1

2

3

4

5

6

7

8

9

10

11

12

13

 

 

 

 

 

 

 

Content   ..  21  22  23  24   ..