TM 5-3805-255-14
0078
ADJUSTMENT CONTINUED
1. Start engine and check for leaks around relief valve (Figure 8, Item 6) and plug (Figure 8, Item 5) at either end
of relief valve.
a. Accelerate engine to full throttle and hold bucket control lever in ROLLED BACK (retracted) position. Note
indicated pressure on gauge.
b. System pressure at full throttle for main relief valve is 2,300 psi (15,858 kPa) plus or minus 50 psi
(345 kPa).
c.
Idle engine. If indicated pressure was not within recommended limits, adjustment is necessary.
d. System pressure at idle is 2,000 psi (13,790 kPa).
e. Always turn adjusting screw clockwise at least one-half turn to set preload.
2. Hold jamnut (Figure 8, Item 4) to remove acorn nut (Figure 8, Item 1) and copper washer (Figure 8, Item 3).
3. Hold adjusting screw (Figure 8, Item 2) and loosen jamnut (Figure 8, Item 4).
4. To adjust pressure, hold jamnut (Figure 8, Item 4) and rotate adjusting screw (Figure 8, Item 2) clockwise to
increase pressure and counterclockwise to decrease pressure.
5. Recheck indicated pressure. When correct pressure is obtained, hold adjusting screw (Figure 8, Item 2) and
tighten jamnut (Figure 8, Item 4).
NOTE
Make sure copper washer is in good condition.
6. Install copper washer (Figure 8, Item 3) and acorn nut (Figure 8, Item 1) on relief valve (Figure 8, Item 6).
WARNING
DO NOT disconnect or remove any hydraulic system line or fitting unless engine is shut
down and hydraulic system pressure has been relieved. Tighten all connections before
applying pressure. Escaping hydraulic fluid under pressure can penetrate the skin,
causing injury to personnel.
Failure to follow warning may result in injury or death to personnel.
7. Stop engine.
8. Relieve pressure in system by moving loader controls through their full travel several times.
9. Relieve reservoir pressure by slowly removing filler cap.
0078-8
