TM-5-3895-372-20

CONCRETE-MOBILE MIXER BODY M919, MODEL 8CM-24/F

TECHNICAL MANUAL; ORGANIZATIONAL MAINTENANCE MANUAL

AUGUST 1980

TM-5-3895-372-20 - Page 472 of 694

TM 5-3895-372-20

Table 10- 1. Hydraulic System Troubleshooting Procedures.

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1.

HYDRAULIC MOTOR DOES NOT OPERATE:

Step 1 Check that tachometer reads 1620-1720 rpm.

Use throttle to adjust engine speed.

Step 2 Check to be sure bypass valve is closed.

Close bypass valve.

Step 3 Check oil level by removing cap and checking dipstick in hydraulic tank.

Add oil if needed (see LO 5-3895-372-12).

Step 4 Check filter for clogging.

Replace clogged filter (see TM 5-3895-372-10).

Step 5 Check hydraulic pump drive belt tension. Belts should deflect 5/32 in. (4.0mm) when

6 lb (27 N-m) pressure is applied.

Adjust drive belts (para 417).

Step 6. Check PTO drive belt tension. Belts should deflect 5/32 in. (,1.0 mm) when 6 lb

(27 N-m) pressure is applied.

Adjust drive belts (para 4-11).

Step 7 Check that proper type of hydraulic oil is being used. (See LO 5-3895-372-12.)

Fill system with correct oil.

Step 8 Check hydraulic lines for oil leaks.

Replace leaking lines on couplings (para 10-15).

Step 9 Check for air leaks at hydraulic pump intake.

Replace leaking line or coupling (para 10-15).

Step 10 Check hydraulic line oil pressure (10-10). Pressure should be 1900-2000 psi

(13,100-13,800 kPa).

Adjust pressure valve (para 10-10).

10-2