TEST OR INSPECTION
HYDRAULIC SYSTEM - CONT
Check for external leaks at hydraulic fittings/joints.
Check hydraulic tank breather cap for restrictions.
Using hydraulic schematic (figure FO-3) as a guide, operate all semitrailer hydraulics and check
hydraulic hoses for internal collapse or obstructions.
Remove and repair or replace hoses as necessary.
Check that system pressure gage (para. 2-5) is not reading higher than 200 psi (1379 kPa) without
hydraulic controls being operated.
If system pressure is higher than 200 psi (1379 kPa), refer to symptom 18 (steps 3 thru 6) to continue
Check that system pressure gage is not reading less than 100 psi (690 kPa) without hydraulic
controls being operated.
Check hydraulic tank filter for obstructions or contamination. Clean or replace hydraulic tank filter
Check hydraulic pump ability to develop pressure by operating front curbside suspension handle
downward (para. 2-6). Monitor system pressure gage. Hydraulic pressure should quickly rise to
3800 - 4500 psi (26201 - 31027 kPa).
a. If pressure rises quickly but fails to reach 3800 - 4500 psi (26201 - 31027 kPa), go to symptom
b. If pressure rises quickly, check nonoperating function by using Symptom Index to continue