power valve adjustment

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,783
3,712
113
Yukon
Arctic Power Valve
(APV) System
NOTE: The servo will activate once at APV cycle
RPM. If the servo cycles three times, cable length
adjustment or valve inspection is required.
NOTE: The 800 cc and 1000 cc have a three-stage
exhaust valve system. The stages are closed, midopen,
and full-open. Each model has a designated
RPM at which the system is synchronized and
checked by the ECU for proper operation. This
occurs once each time the engine is started. The
800 cc system is checked at 4800 RPM and the
1000 cc system is checked at 6100 RPM (Crossfire/
F-Series) or at 6270 RPM (M-Series

APV CABLE LENGTH
ENGINE MODEL CENTER ± 1 mm (0.039 in.)
600 cc 36.0 mm (1.417 in.)
800/1000 cc 35.0 mm (1.377 in.)
 

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,783
3,712
113
Yukon
CABLE ADJUSTMENT
Proper cable adjustment is critical to the operation of
the APV system. While it is recommended that the
cable adjustment be inspected every 1000-2000 miles,
the cable should not need adjustment often. To check
the cable adjustment, use the following procedure.
1. On the Crossfire/M-Series, remove the two cap
screws securing the servomotor cover.
2. Using a small needle-nose pliers, remove the servomotor
retaining clip and the cable holder.
CM126A
CM127
3. Rotate the servomotor actuator counterclockwise
to loosen the cable; then pull the cable housings
down and out of the servomotor.
CM123A
4. Slide each cable drum out of the slot of the servomotor
actuator.
CM124A
��NOTE: Before proceeding with the cable adjustment,
ensure that the exhaust valves are free to
move.
5. While holding the cable housing firmly, pull the
cable as far out as it will go; then release. Repeat
three to four times. The cable/exhaust valve
should move freely without binding. If the cable/
exhaust valve does not move freely, the exhaust
valve assembly will need to be removed for further
inspection.
��NOTE: When measuring the cables, they are to
be routed and as close to their installed position
as possible.
6. While holding the cable housing, lightly pull on
one cable end to remove any slack.
7. Measure the amount of exposed cable from the
cable housing to the end of the cable.
��NOTE: The two cable measurements must be
equal in length or less than 0.5 mm (0.020 in.) difference
in length from each other.
��NOTE: Repeat steps 6 and 7 for each cable; then
compare the measurements to the appropriate
chart.

��NOTE: The measurements must be within the
specifications from the chart. If the measurements
are within specifications, no adjustment is necessary.
If they are not within specifications, proceed
to step 8.
8. Loosen the jam nut on the cable to be adjusted;
then using the adjusting nuts, lengthen or shorten
the housing as needed.
9. Once the proper length has been attained, hold the
adjusting nut in place and tighten the jam nut
securely.
10. Place the cable housings into position in the servomotor.
Secure the cable housings with the cable
retaining cover.
11. On the Crossfire/M-Series, place the servomotor
cover into position; then secure with two cap
screws.
��NOTE: If for any reason the pulley was removed
from the servo, make certain to align the space
between the two cables with the mark on the shaft
of the servo.
MS401A
 

whittaker727

Well-known member
Nov 26, 2007
3,901
275
83
Naples, Id
So, I'm feeling pretty stupid right now, but sitting without the motor running and the valves completely closed, how much cable should be sticking out? 1.377" or is that at a different rpm setting? If you're looking at the servo motor from the front of the sled, which way should the cables come in from? There are two sets of cable slots for some reason.
 

JHG

Well-known member
Jan 30, 2008
2,437
518
113
Elizabeth, CO/Bozeman, MT
So, I'm feeling pretty stupid right now, but sitting without the motor running and the valves completely closed, how much cable should be sticking out? 1.377" or is that at a different rpm setting? If you're looking at the servo motor from the front of the sled, which way should the cables come in from? There are two sets of cable slots for some reason.
Cables come from the motor side of the cam. The 35mm or 1.377 is with the valves closed. The cam rotates clockwise when it opens.
 
Nov 28, 2019
6
0
1
CABLE ADJUSTMENT
Proper cable adjustment is critical to the operation of
the APV system. While it is recommended that the
cable adjustment be inspected every 1000-2000 miles,
the cable should not need adjustment often. To check
the cable adjustment, use the following procedure.
1. On the Crossfire/M-Series, remove the two cap
screws securing the servomotor cover.
2. Using a small needle-nose pliers, remove the servomotor
retaining clip and the cable holder.
CM126A
CM127
3. Rotate the servomotor actuator counterclockwise
to loosen the cable; then pull the cable housings
down and out of the servomotor.
CM123A
4. Slide each cable drum out of the slot of the servomotor
actuator.
CM124A
��NOTE: Before proceeding with the cable adjustment,
ensure that the exhaust valves are free to
move.
5. While holding the cable housing firmly, pull the
cable as far out as it will go; then release. Repeat
three to four times. The cable/exhaust valve
should move freely without binding. If the cable/
exhaust valve does not move freely, the exhaust
valve assembly will need to be removed for further
inspection.
��NOTE: When measuring the cables, they are to
be routed and as close to their installed position
as possible.
6. While holding the cable housing, lightly pull on
one cable end to remove any slack.
7. Measure the amount of exposed cable from the
cable housing to the end of the cable.
��NOTE: The two cable measurements must be
equal in length or less than 0.5 mm (0.020 in.) difference
in length from each other.
��NOTE: Repeat steps 6 and 7 for each cable; then
compare the measurements to the appropriate
chart.

��NOTE: The measurements must be within the
specifications from the chart. If the measurements
are within specifications, no adjustment is necessary.
If they are not within specifications, proceed
to step 8.
8. Loosen the jam nut on the cable to be adjusted;
then using the adjusting nuts, lengthen or shorten
the housing as needed.
9. Once the proper length has been attained, hold the
adjusting nut in place and tighten the jam nut
securely.
10. Place the cable housings into position in the servomotor.
Secure the cable housings with the cable
retaining cover.
11. On the Crossfire/M-Series, place the servomotor
cover into position; then secure with two cap
screws.
��NOTE: If for any reason the pulley was removed
from the servo, make certain to align the space
between the two cables with the mark on the shaft
of the servo.
MS401A
So i have a 2007 artic cat f8 sno pro and i was checking the servo and i turned it counterclock wise and the cables got lose . So i panicked and took the cables out to find out out ones stretched doesnt open and close like the other one does . But i do not know how to turn that servo back to where it was . It wont let me turn it either way ?
 

Readymedic

Well-known member
Premium Member
Nov 6, 2013
372
76
28
Saskatchewan Canada
Make sure your cables are on right. I had a dealer put them on wrong, so they wouldn't open. Check that.
The servo will turn by its self, to adjust, but don't put the cables in. Let it adjust, then put them in. Always check your cable lengths. Don't rely on your servo to tell you that they are out of adjustment. Always measure will a caliper.
 
Nov 28, 2019
6
0
1
How do i adjust the servo without the cables on it ? Do i need to fire it up or just turn the key ? Im not smart in this stuff my bad haha
 

Readymedic

Well-known member
Premium Member
Nov 6, 2013
372
76
28
Saskatchewan Canada
I DO NOT MEAN THAT THE CABLES WIll ADJUST BY THEM SELFS.....YA IMPOSSIBLE.
What I mean is that when the cables are off, rev the motor. The servo will find its neutral spot so it can begin to turn, when the cables are put back on. The other guy said, if I turn it, where do I turn it back too. It will go that position by itself.
 
Nov 28, 2019
6
0
1
I hooked the cables up.before i saw this but i fired up the sled and had er full pin i think.it went back to its normal position it didnt throw a check engine light or anything so i should be good
 
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