Tractor Operates Erratically; Tractor Operates In Both Directions But With Loss Of Power; Condition Becomes Worse As Transmission Becomes Hot; Transmission Overheating - Toro 520XI Service Manual

HYDROSTATIC DRIVE
TROUBLESHOOTING (cont'd)

Tractor operates erratically.

Possible Cause
The transmission control linkage needs adjustment or
replacement
The transmission oil level is low
The transmission is faulty

Tractor operates in both directions but with loss of power.

Condition becomes worse as transmission becomes hot.

Possible Cause
The transmission oil level is low
The transmission shows signs of overheating or water
contamination
The cooling fan and/or transmission cooling fins are
3
faulty or dirty
The engine is not operating at full throttle
The power steering filter is dirty

Transmission overheating.

Possible Cause
Not operating engine at full throttle
Low oil level
Accumulation of dirt and debris on hydrostatic trans.
Loose fan or broken blades

Abnormal vibration or noise.

Possible Cause
The engine mounting bolts are loose
The idler pulley or cutter deck blade is loose
The transaxle cooling fan is loose
There is a problem with the electric clutch
3 - 4
Corrective Action
Adjust, repair, or replace
Fill to the full "F" mark on the transmission oil dipstick
when transmission is cold
Repair/replace
Corrective Action
Fill to the full "F" mark on the transmission dipstick
when transmission is cold
Replace the transmission oil and filter
Clean the transmission and/or replace the fan.
Increase the engine speed to full throttle
Clean the power steering filter
Corrective Action
Increase engine speed to full throttle
Fill full "F" mark on dipstick (when trans. is cold)
Clean
Repair or replace
Corrective Action
Tighten the engine mounting bolts
Tighten the appropriate pulley
Repair or replace as necessary
Repair or replace as necessary
5xi Series Tractor Service Manual