Testing; Solenoid Identification; Test For Clutch Leakage - Manitowoc Grove CD3340B Service Manual

CD3340B/YB4411
1. The speed sensor is inoperable (Check speed sensor
and installation.
2. Shift control switch contact or wiring problems.
Erratic / Sticking Gears
It is possible that a mechanical issue is the cause of this
problem. A known problem is if the transmission has at some
point suffered coolant failure and water has entered the
transmission. If the original plastic clutch pistons are still
being used then there is a risk that they will stick.

TESTING

Solenoid Identification

When Testing Individual Clutch Pressures (It Is necessary to
isolate the clutch being tested. For instance, to check the
layshaft clutch, you could select 1st gear forward. This would
energize the layshaft and forward low clutches. Because we
only want to check the layshaft clutch pressure and not the
forward low clutch pressure, remove the electrical connector
to the forward low clutch BEFORE selecting 1
Use the Tables 5-3 and 5-4 to determine which solenoid
electrical connectors should be removed when pressure-
testing individual clutches. Table 5-3 identifies the solenoid
connectors (see Figure 7-12) and Table 5-4 identifies which
clutches are engaged when the various gears are selected.
a0248
GROVE
gear.
st
MS
RH
FL
FH
RL
LS
FIGURE 7-12
Published 04/07/2015 Control # 569-00
TRANSMISSION AND TORQUE CONVERTER
Table 5-3
Solenoid Description
Item Solenoid Description
RL Reverse Low
RH Reverse High
LS Layshaft
MS Mainshaft
FH Forward High
FL Forward Low
Table 5-4
Solenoid Valve Energizing Sequence
Gear Direction Clutches Engaged Solenoids
First Reverse Reverse Low & Layshaft, RL &LS
Second Reverse Reverse High & Layshaft RH & LS
Third Reverse Reverse Low & Mainshaft RL & MS
Fourth Reverse Reverse High & Mainshaft RH & MS
First Forward Forward Low & Layshaft FL & LS
Second Forward Forward High & Layshaft FH & LS
Third Forward Forward Low & Mainshaft FL & MS
Fourth Forward Forward High & Mainshaft FH & MS

Test For Clutch Leakage

WARNING
DO NOT go under the crane with the engine running. Turn
off the engine, apply the parking brake, chock the wheels
and remove the ignition key before going underneath the
crane.
Isolating a Suspect Clutch
Stop the engine, connect a 0-2040 kPa (0-300 psi) pressure
gauge to the test connector A, Figure 7-13 (mainline
pressure test point).
Make sure that both sides of all four wheels are chocked.
Apply the foot brake and the parking brake.
Start the engine and run at 1000 rpm. Engage1
forward. Record the pressure reading. Repeat the test for all
gear ratios in forward drive and record the pressure readings
as shown below.
Readings should not vary between clutches by more than 69
kPa (10 psi). In the example shown, we can see that
pressure is low when 2 and 4
nd
indicating clutch leakage.
From the example you can see that the forward clutch high is
used for selection of both 2
nd
from the table that the mainshaft and the layshaft clutches
gear
st
gear forward is selected,
th
and 4 gear forward. We know
th
7-21
7