OPERATOR'S MANUAL MAINTENANCE

Section E - Hydraulics
Fault Finding
Relief Valve
E-236 E-236
9803/9880-3
Relief Valve
Table 2.
Symptoms Possible Causes Countermeasures
Pressure does not rise at all 1. The main poppet, sleeve or pilot poppets
are sticking open or foreign matter is in the
valve seat.
1 Check whether foreign matter is in
each poppet.
2 Check whether each part is sliding
smoothly.
3 Clean all the parts.
Relief pressure is unstable 1. The pilot poppet seat is damaged. Replace the damaged parts.
2. The piston is sticking to the main poppet. Remove the surface scratches. Clean all
the parts.
Relief pressure is out of control 1. Wear due to foreign matter. Replace the worn parts
2. Lock nut and adjuster are loose. Reset the pressure and tighten the lock nut
to the rated torque.
Oil leakage 1. Damaged seat or worn O-ring. Replace damaged or worn parts. Check
whether each part is sliding smoothly.
2. Parts are sticking due to foreign matter. Check for scratches, cuts or foreign matter.
Clean all the parts.