TM 5-3810-295-34
(3) The following are considered the minimum actions
verter to warm the oil.
to be taken:
c. To stall the converter, shift the transmission to
(a) Drain the entire system thoroughly.
forward and fourth speed and apply brakes. Accelerate
(b) Disconnect and clean all hydraulic lines. Where
engine to one half to three quarter throttle and hold until
feasible, hydraulic lines should be removed from
desired converter temperature is reached.
machine for cleaning.
WARNING
(c) Replace oil filter elements, cleaning out filter
Full throttle stall speed for an excessive
cases thoroughly.
length of time will overheat and damage
(d) The oil cooler must be thoroughly cleaned. The
the torque converter.
cooler should be "back flushed" with oil and com-pressed
d. Check oil pressure at converter outlet, Fig.12-5,
air until all foreign material has been removed. Flushing
Check point C.
in direction of normal oil flow will not ade-quately clean
(1) Install 100 PSI gage in converter outlet port.
the cooler. If necessary, radiator should be removed
(2) Converter out pressure should be 70 PSI at
from machine for cleaning, using oil, com-pressed air,
2000 RPM.
and steam cleaner for that purpose.
(3) High converter out pressure indicates a
CAUTION
restricted oil cooler.
e. Check charging pump output, Fig.12-5.
DO NOT use flushing compounds for
cleaning purpose.
(1) Install flowmeter in line between charging pump
mounted on rear of torque converter and oil filter.
(e) Remove bottom drain cover and plug from
(2) Charging pump output for a new pump is 31
torque convert and inspect interior of converter housing,
GPM at 2000 RPM.
gars, etc.(Fig.15-11).If considerable foreign material is
(3) If output is less than 25 GPM at 2000 RPM,
noted, it will be necessary that converter be removed,
replace the charging pump.
disassembled, and cleaned thoroughly.
f. Check transmission clutch pressures, Fig.12-5,
(f) Reassemble all components.
Using OES
Check point A.
10engine of; fill torque converter and transmission
(1) Install 300 PSI gage in test port on transmission
through filer opening until fluid comes up to FULL mark
control valve.
on transmission dip-stick. Reinstall fill plug and dip-stick
(2) Run engine at low idle with converter oil
and run engine two minutes at (500-600 rpm) to prime
temperature at 180-200 F.
torque converter and hydraulic lines. Recheck level of
(3) Shift transmission through all speed ranges and
fluid in transmission with engine running at idle (500-600
record pressure for each range.
rpm) and add quantity necessary to bring level up to
(4) All clutch pressures must be 180-220 PSI and
FULL mark on dip-stick. Recheck with hot oil (180to
be equal within 5 PSI.
2000).
g. Check transmission clutch leakage, Fig.12-5.
(g) Recheck all drain plugs, connections, etc., for
(1) Install a flowmeter in the line between the
leaks and tighten where necessary.
conveyer charging pump and the oil filter.
(2) Check and record pump volume at low engine
12-7.1 Transmission System Testing
idle and at 2000 RPM.
NOTE
(3) Install flowmeter in "converter in line" between
The following tests consider the torque
transmission and converter.
converter, transmission, charging pump, of
(4) Check and record oil volume at low engine idle
cooler and lines as a complete system.
and at 2000 RPM in all speed ranges.
a. Prior to starting engine and checking system from
(5) Subtract reading for each speed range from
a hydraulic standpoint, check for mechanical defects.
pump volume readings taken in sub-para g.(2) above.
(1) Make sure shift lever properly installed and
This is transmission clutch leakage.
adjusted.
(6) If clutch leakage varies more than one gallon,
(2) Check shift lever for binding or restriction in
or if total leakage of all clutches exceeds four gallons,
travel that would prevent full engagement.
repair the transmission.
CAUTION
h. Check torque converter lube flow, Fig.12-5.
Do not stall out converter for more than 30
(1) Disconnect "converter return line" at the
seconds continuous stall.
transmission.
b. Check oil level in transmission with temperature
of 180-200F. Either work the machine or stall the con
Change 1 12-5
