Torque Specifications; Fastener Identification - Toro 400XT Series Service Manual

SPECIFICATIONS

Torque Specifications

Recommended fastener torque values are listed in the
following tables. For critical applications, as determined
by Toro, either the recommended torque or a torque
that is unique to the application is clearly identified and
specified in the service manual.
These torque specifications for the installation and
tightening of fasteners shall apply to all fasteners which
do not have a specific requirement identified in the
service manual. The following factors shall be
considered when applying torque: cleanliness of the
fastener, use of a thread sealant (Loctite), degree of
lubrication on the fastener, presence of a prevailing
torque feature, hardness of the surface underneath of
the fastener's head, or similar condition which affects
the installation.
As noted in the following tables, torque values should
be reduced by 25% for lubricated fasteners to
achieve the similar stress as a dry fastener. Torque
values may also have to be reduced when the fastener
is threaded into aluminum or brass. The specific torque
value should be determined based on the aluminum or
brass material strength, fastener size, length of thread
engagement, etc.
The standard method of verifying torque shall be
performed by marking a line on the fastener (head or
nut) and mating part, then back off fastener 1/4 of a
turn. Measure the torque required to tighten the
fastener until the lines match up.
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Fastener Identification

Figure 1
Inch Series Bolts and Screws
(A) Grade 1
(B) Grade 5
Figure 2
Metric Bolts and Screws
(A) Class 8.8
400XT Series Tractor Service Manual
(C) Grade 8
(B) Class 10.9