North American Clutch & Driveline
Rockford, Illinois
Phone: (800) 383-9204
(815) 282-7960
Fax (815) 282-9160
www.naclutch.com
3.4.1 Torque Wrench Method (Preferred Method)
A torque wrench should be used at the cross shaft to measure engagement force. The
following chart shows torque readings that represent proper clutch engagement force.
The clutch should ENGAGE within the torque readings shown.
An adapter, NACD Part Number 236484AM may be obtained to provide a 1 1/2” hex
nut at the end of the cross shaft. The adapter may be used in place of the standard
handle for the purpose of checking clutch adjustment with a torque wrench, or it may be
installed on the end of the cross shaft opposite the standard handle. All NACD handles
are cast with this hex. (Most PTO’s have serations on both ends of the cross shaft.)
Note: These values include a 15% allowance for friction
within the clutch release mechanism.
3.4.2 Spring Scale Method Using A Standard Handle
Determine whether the engagement force is correct.
Measure the distance from the bottom of the handle grip
location to the center of the cross shaft. Attach a spring
scale to the handle at the location specified below and
pull the scale perpendicular to the handle to measure the
force required to engage the clutch.
10
Clutch Size
14” HD & HD (DP)
14” HD & HD (TP)
Handle Length
Cross Shaft to Grip
Release Yoke
Length
Engagement Force
80-90 lbs. (356-400N.)
72 lbs.(320 N.)
68 lbs.(302 N.)
4.0" (10.16 cm.)
21" (53.3 cm.)
4.5" (11.43 cm.)
21" (53.3 cm.)
Original Setting
10% Decrease
15% Decrease
90-120 lbs. (400-534N.)
81 lbs. (360N.)
77 lbs. (342N.)
Original Setting
10% Decrease
15% Decrease
Yoke Length
4.0” Release Yoke
4.5” Release Yoke
Torque @ Cross-Shaft to Engage Clutch
163 to 183 ft. lbs. (221 to 248 Nm.)
183 to 208 ft. lbs. (248 to 282 Nm.)
Length