Changing Rear Transaxle Differential Oil; Servicing Closed Loop Hydrostatic Drive Circuit; Servicing Hydraulic Oil Cooler; Checking Engine Rpm - Ventrac 4500Y Operator's Manual

Changing Rear Transaxle Differential Oil

1. Remove the rear weights from the hitch bar (if
equipped).
2. Place a drain pan (minimum 6 quart / 5.5 liter)
under the rear transaxle.
3. Remove the drain
plug (B) from the
rear transaxle and
allow the hydrau-
lic oil to drain
from the system.
Remove the oil fill
plug (C) from the
rear transaxle to
allow venting.
NOTE: on some
power units, it may be necessary to remove the
rear transaxle skid plate to access the drain plug.
4. Clean the drain plug and apply pipe sealant to
the threads, making sure to leave the last two
threads bare to prevent thread sealant from con-
taminating the hydraulic fluid.
5. Reinstall the plug into the rear transaxle and
tighten 1 - 2 turns past finger tight (approxi-
mately 8-12 ft-lbs / 11-16 Nm of torque).
CAUTION
Do not over tighten the transaxle plug. Over-tight-
ening can cause the transaxle case to crack.
6. Add HydroTorq XL synthetic hydraulic oil
(approximately 4 qt / 3.8 L) to the fill port in the
rear transaxle until level with the bottom of the
oil fill hole.
7. Clean the oil fill plug and apply pipe sealant to
the threads, making sure to leave the last two
threads bare to prevent thread sealant from con-
taminating the hydraulic fluid.
SERVICE
B
C
8. Reinstall the plug into the rear transaxle and
tighten 1 - 1-1/2 turns past finger tight (approxi-
mately 35-40 ft-lbs / 48-54 Nm of torque).
9. If the rear transaxle skid plate was removed to
access the drain plug, reinstall the skid plate.
10. Reinstall the rear weights (if equipped).
Servicing Closed Loop Hydrostatic Drive
Circuit
Service or repair of the closed loop drive circuit must
be performed by an authorized Ventrac dealer.
If any part of the closed loop hydrostatic drive
circuit (pump, front drive motor, rear drive motor,
or any of the three 1/2" hydraulic lines connecting
them together) is serviced or replaced, the Ven-
trac closed loop drive circuit filtration procedure
must be performed. This procedure requires a
special Ventrac remote filtering tool and must be
performed by a Ventrac authorized technician.

Servicing Hydraulic Oil Cooler

1. Brush dirt and debris from the oil cooler screen
in the right fender.
2. With the ignition key turned to the run position, flip
the oil cooler fan switch from "auto" to "reverse"
operation to blow dust off the oil cooler fins.
3. Place the fan switch back in the "auto" position.

Checking Engine RPM

Check engine RPM when engine is warmed up and
not under load. Observe tachometer:
• Low idle speed = 1500 ±50 RPM
• High idle speed = 3600 ±50 RPM
If engine RPM is incorrect, contact your local Ven-
trac dealer.
Service - 43
Attention