SPEED GEAR ASSEMBLY (REVERSER)

TM 5-2420-222-20-1

TRANSMISSION SYSTEM -CONTINUED

When clutch pedal is released to engage engine flywheel clutch, clutch control pressure valve spool routes

hydraulic pressure to clutch control shift valve spool to engage selected speed gear assembly (reverser) clutch

pack.

Speed gear assembly (reverser) speed of shift can be adjusted by turning screw at adjustable accumulator

charging orifice to change control valve accumulator charging rate. Adjusting orifice smaller shows pressure rise in

selected speed gear assembly (reverser) clutch pack for smoother, softer shift. Adjusting orifice larger speeds

pressure rise, Increasing torque under load but making shift sharper under no load.

SPEED GEAR ASSEMBLY (REVERSER)

Connected in power train between clutch and transmission.

Separate clutch packs for forward and reverse engagement allow constant mesh of gear train for change In

direction under full load without shifting transmission gears.

TRANSMISSION RANGE SHIFT LEVER

Reaches directly into transmission from operator's compartment.

Allows operator to select low range (I) or high range (II). On loader backhoes with Serial Numbers 235786 thru

235999, speed gear assembly (reverser) control lever must be in forward drive position to operate transmission in

high range (II).

TRANSMISSION GEAR SHIFT LEVER

Reaches directly into transmission from operator's compartment.

Allows operator to select gears 1 thru 4 when transmission range shift lever is in low range (I).

Allows operator to select gears 5 thru 8 when transmission range shift lever is in high range (11).

TRANSMISSION

Connected in power train between speed gear assembly (reverser) and differential.

Mechanical, collar shift type with helical gears in constant mesh. Depending upon transmission range and gear

shift lever positions, some gears are allowed to idle on shafts while shifters engage others by forcing Internally

splined shifter collars, geared to shafts by shifter gears, over short external splines on sides of gears to be driven.

Different speed ratios are obtained by engaging different combinations of gears.

Provides eight forward speeds.

Provides four reverse speeds in low range (I) only on loader backhoes with Serial Numbers 235786 thru 235999,

which are equipped with high speed lockout for reverse.

Provides eight reverse speeds, including four in low range (I) and four in high range (II), only on loader backhoes

with Serial Numbers 319995 thru 342573.

Acts as hydraulic fluid reservoir for all hydraulic system components.

TRANSMISSION DIPSTICK

Dipstick gage shows transmission hydraulic fluid level.

Closes end of transmission filler tube to keep dirt out of tranmission system.

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