Cause / 704

1. Air mixed with oil. 2. Oil return tube loose. 3. Oil bypassing 4. System overfilled. 5. Restriction in cylinder orifice.

Repair / 704

1. Change oil to proper weight hydraulic oil or tighten all suction line fittings. 2. Reinstall return tube. 3. Replace relief valve and/or rings on pressure side of pump. 4. Bleed cylinders and check oil level. Remove excess oil. 5. Remove cylinder bleed screw and clear orifice.