DRESSTA TD-25M EXTRA, Service Manual

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SECTION 7
DRIVE TRAIN
Page 28
TD-25M EXTRA DRESSTA
SERVICE DIAGNOSIS
2. Use pennies (or small metal disks having
φ
21.3 [mm] and 2 [mm] in diameter and thickness
respectively) (6, Fig. 7.9) and place them over the ports for FC, RC, 1C, 2C, 3C on the
underside of the range selector valve (10) (the US penny will just fit inside transmission manifold
(2) ports O-rings, so they will be held in place). Reinstall the valve and tighten it down, with coins
(or metal disks) in place. This effectively shuts off any flow to the clutch packs so no clutch
engagement is possible, but the lube flow is not interrupted, so there is no danger of damage to
the transmission during this test.
3. Start the engine and take all drive train pressures again. The pressures should be taken in all
ranges and in both directions; refer to TRANSMISSION AND TORQUE CONVERTER OIL
PRESSURE TEST in this Section. Shut off the engine.
4. If the pressures which were low on the first test are NOW correct , the problem is internal to the
transmission and it will have to be removed and repaired (for more details refer to Transmission
and Torque Converter Diagnostic Chart in this Section).
5. If the pressures are still low, the problem is outside of transmission, probably in the transmission
valves.
6. Remove the pennies or metal disks; reinstall the range selector valve with O-rings, refer to
RANGE SELECTOR VALVE in TRANSMISSION, SECTION 7C.
16. STEERING SYSTEM SUPPLY PRESSURE TEST
Fig. 7.10. Steering System Supply Pressure Test
1. Transmission
2. Hydraulic Tee
3. Steering Valve Supply Hose
4. Steering Valve
5. Rear Main Frame