OPERATION
FN180/FN120 01/11 Operation Section 4-6
© 2011 Alamo Group Inc.
OPERATION
2.6 Front End Weight
A minimum of 20% total tractor weight must be maintained on the tractor front end at all times. Front end
weight is critical to maintain steering control and to prevent the tractor from rearing up while driving. If the
front end is too light, add weight until a minimum of 20% total weight is reached on the front tires. Front
weights and weight carriers can be purchased through an authorized tractor dealership. OPS-U- 0005
2.7 Power Take Off (PTO)
Depending on the unit, the mower is designed to operate at a PTO speed of 540 or 1000 RPM. Most tractors
operate at either 540, or a combination of 540 and 1000 RPM PTO speeds. The operating speed of the
mower and tractor can be determined by the number of splines on the driveline yoke and PTO output shaft.
Those operating at 540 RPM will have a 6-spline shaft and those operating at 1000 RPM will have a 21-spline
shaft or a 1-3/4” 20 spline shaft. Refer to the tractor owner’s manual for instructions to change PTO speeds on
models that operate at more than one speed.
If operating an older model tractor where the tractor’s transmission and PTO utilize one master clutch, an
over-running clutch must be used between the PTO output shaft and the driveline of the mower. An
authorized tractor dealer can provide the over-running clutch and its installation if needed. OPS-U- 0006
DO NOT use a PTO adapter to attach a non-matching Implement driveline to a Tractor
PTO. Use of an adapter can double the operating speed of the Implement resulting in
excessive vibration, thrown objects, and blade and implement failure. Adapter use will also
change the working length of the driveline exposing unshielded driveline areas. Serious
bodily injury and/or equipment failure can result from using a PTO adapter. Consult an
authorized dealer for assistance if the Implement driveline does not match the Tractor PTO.
(S3PT-14)
Never operate the Tractor and Mower if the Implement input driveline is directly connected
to the Tractor transmission. Tractor braking distances can be substantially increased by
the momentum of the rotating Mower blades driving the Tractor transmission even though
the Tractor clutch has been disengaged. Install an over running clutch between the Tractor
PTO and the Mower driveline to prevent this potentially dangerous situation.
(S3PT-16)