Polaris RANGER XP 1000 2018-2019, Service Manual

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9929399 R01 - 2018-2019 RANGER XP/ CREW 900/1000 Service Manual
© Copyright Polaris Industries Inc.
MEASUREMENT
Intake Seat Cutter Diameter:
1.457 in. (37.00 mm)
MEASUREMENT
Exhaust Seat Cutter Diameter:
1.260 in. (32.00 mm)
MEASUREMENT
Valve Seat Width:
Intake: 0.039" (1.00 mm)
Service Limit: 0.055" (1.4 mm)
Exhaust: 0.059” (1.50 mm)
Service Limit: 0.075" (1.9 mm)
8. Clean all filings from the area with hot soapy water.
Rinse and dry with compressed air.
9. Lubricate valve guides with clean engine oil and
apply oil or water based lapping compound to the
face of the valve.
NOTICE
Lapping is not required if an interference angle
reconditioning method is used.
10. Insert the valve into its respective guide and lap
using a lapping tool or a section of fuel line
connected to the valve stem.
11. Rotate the valve rapidly back and forth until the cut
sounds smooth. Lift the valve slightly off of the seat,
rotate 1/4 turn, and repeat the lapping process. Do
this four to five times until the valve is fully seated,
and repeat process for the other valve(s).
12. Thoroughly clean cylinder head and valves.
VALVE SEAT RECONDITIONING (1000)
Valve seat reconditioning should be performed by a
technician proficient in cylinder head reconditioning
techniques. Reconditioning techniques vary, so follow
the instructions provided by the valve reconditioning
equipment manufacturer. Do not grind seats more than
necessary to provide proper seat surface, width, and
contact point on valve face.
CAUTION
Wear eye protection or a face shield during cylinder
head disassembly and reassembly.
Valve Seat Inspection
Inspect valve seat in cylinder head for pitting, burnt
spots, roughness, and uneven surface. If any of the
above
conditions exist, the valve seat must be
reconditioned. If the valve seat is cracked the cylinder
head must be replaced.
Valve seat width and point of contact on the valve face is
very important for proper sealing. The valve must contact
the valve seat over the entire circumference of the seat,
and the seat must be the proper width all the way
around. If seat is uneven, compression leakage will
result. If seat is too wide, seat pressure is reduced,
causing carbon accumulation and possible compression
loss. If seat is too narrow, heat transfer from valve to seat
is reduced. The valve may overheat and warp, resulting
in burnt valves.
Renewing Valve Seats
1. Install pilot into valve guide.
2. Apply cutting oil to valve seat and cutter.
3. Place 46° cutter on the pilot and make a light cut.
ENGINE / COOLING / HVAC SYSTEM