Toro 91764SL User Manual

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

________________________________________________________________________________________________________________________________________________________ 

The cause of an improperly functioning hydraulic sys­
tem is best diagnosed with the use of proper testing 
equipment and a thorough understanding of the com­
plete hydraulic system. 

A hydraulic system with an excessive increase in heat 
or noise is a potential failure. Should either of these 
conditions be noticed, immediately stop the machine, 
turn off the engine, locate the cause of the trouble, and 
correct it before allowing the machine to be used again. 
Continued use of an improperly functioning hydraulic 

system could lead to extensive internal component 
damage. 

The charts that follow contain detailed information to 
assist in troubleshooting. There may possibly be more 
than one cause for a machine malfunction. All causes 
should be checked in the order in which they are listed 
on the charts. 

Refer to the Testing section of this Chapter for precau­
tions and specific test procedures. 

Faulty traction control linkage. 

Repair linkage 

Transmission charge check valve defective. 

Inspect and clean or replace charge/check. 

Faulty control linkage. 

Repair linkage 

Parking brake engaged. 

Disengage parking brake. 

Hydraulic oil level too low. 

Fill to proper level. 

By-pass valve open. 

Close by-pass valve. 

Clogged hydraulic filter. 

Replace filter. 

Low charge pressure - Test A. 

Inspect charge relief valve and replace if faulty. 

Inspect charge pump and replace if faulty. 

Low traction pump flow/pressure - Test B. 

Repair or replace pump. 

Low traction motor efficiency - Test C. 

Repair or replace traction motor. 

HydroJect

™ 

3000