TM 10-3930-671-24 Hydraulic Sump Fluid Level Check Correct    fluid    level    is    important    for    proper    hydraulic system operation: • Low fluid level can cause pump damage. • Overfill   can   cause   loss   of   fluid   or   lift system malfunction. • Because  of  the  expansion  of  fluid  as  its temperature rises, it is preferable to check the   fluid   level   at   operating   temperature (after  approximately  30  minutes  of  truck operation). 1. Check the hydraulic sump tank fluid level daily. 2. To check fluid level, park truck on a level surface and  apply  the  parking  brake.  Put  upright  in  a vertical   position   and   lower   fork   carriage   fully down. 3. Pull  the  dipstick  out,  wipe  it  with  a  clean  wiper, and    reinsert    it    fully    into    the    dipstick    tube. Remove the dipstick and check the oil level. 4. Keep  the  oil  level  above  the  LOW  mark  on  the dipstick  by  adding  recommended  hydraulic  fluid only as required. DO NOT OVERFILL. 5. Check the PM time interval (operating hours) or the  condition  of  the  hydraulic  fluid  (age,  color, clarity,   contamination,   etc.)   to   determine   if   it needs  to  be  changed.  Change  (replace)  the  oil, as necessary. Refer to Section 2.1, Service Specifications, for hydraulic oil specifications. Hydraulic Fluid & Filter Change It is recommended to: • Drain and replace the hydraulic sump fluid every 2000 operating hours, or sooner, as required. • Replace the hydraulic oil filter at every oil change,   or   every   500   hours,   whichever occurs sooner. • Replace  the  sump  tank  breather/fill  cap every 500 operating hours, or as required. There  is  no  drain  plug  in  the  hydraulic  sump  tank.  The hydraulic  fluid  can  be  changed  by  one  of  the  following methods: 1. Removal    of    the    hydraulic    sump    tank    cover assembly  and  pumping  the  fluid  out  by  suction using a separate pump and hose. 2. By connecting a quick-disconnect coupling to the test   port   and   pumping   the   fluid   out   using   the truck   hydraulic   system.   This   method   may   be used   most   easily   and   satisfactorily   for   routine changes of the fluid. Refer    to    Section    10.    1,    Main    hydraulic    System Maintenance, for additional information. Hydraulic Oil Filter Remove and replace the hydraulic system fluid filter per recommended  PM  schedule,  or  as  may  be  required  by truck operating conditions and usage. Refer    to    Section    10.    1,    Main    Hydraulic    System Maintenance, for additional information. Sump Tank Breather Maintenance 1. Remove   the   sump   tank   breather/fill   cap   and inspect   for   excessive   (obvious)   contamination and damage. 2. Replace  the  breather/fill  cap,  per  recommended PM    schedule,    or    as    required    by    operating conditions. Refer     to     Section     10.1,     Main     Hydraulic     System Maintenance, for additional information. Access To the Transaxle Transaxle Fluid An upright or carriage can move unexpectedly. Chain or block the carriage and each rail. FAILURE TO FOLLOW THIS WARNING CAN RESULT IN SERIOUS INJURY NOTE If you are unfamiliar with  this  procedure,  please  refer  to Section 3.3, Machine Jacking and Blocking, for information on blocking the upright in raised position. The   best   method   to   use   for   reaching   the   transaxle checkpoints    (oil    level/filler    plug    and    drain    plugs)    is dependent    upon    the    style    of    upright,    carriage,    and attachments  on  your  truck.  One  method  is  to  raise  the upright carriage to provide easier access to the transaxle from the front. See illustration. Apply the parking brake and block the wheels. Be sure to put blocking under the carriage and upright rails. F-52