SHOP MANUAL
Paragraphs 155-158
16 Fig. 134-On Modei L260, rockshaft feedback linkage is adjusted at turnbuckie on link (L).
shown in Fig. 132. Temporarily loosen transport stop (U-Fig. 131). Run engine at about half throttle and move hand lever to raising position; rockshaft should raise and gage pressure should rise to specified relief pressure. Hold hand lever in RAISE position for ten seconds. Gage pressure should remain steady; a substantial drop in pressure would indicate a worn pump or serious pressure leak. If a pressure gage is not available, lifting capacity at tip of lower links should be 600 kg (1325 pounds). To adjust relief pressure, it is first necessary to remove lift cover and turn adjusting screw (46-Fig. 148) on control valve body. DO NOT hold relief valve open longer than 15 seconds. Reset transport stop after pressure has been adjusted or checked. Model L210 155. LIFT POSITIONING STOPS. Positioning stops (U & D-Fig. 133) can be moved on linkage rod to manually return control lever to neutral at a preset rockshaft position. Transport stop (U) should be set to neutralize valve just before rockshaft piston reaches end of its stroke and should not normally be moved. Working depth stop (D) can be moved as desired. System provides no automatic (feedback) correction to compensate for leakage.
Fig. 137-if hydrauiic pump wiii not prime, ioosen accessory plate (P} or pressure line fitting (F} to relieve vapor lock at back pressure valve.
Fig. 136-Expioded view of hydrauiic pump, drive housing and Hnes used on Modeis L775, L22S and L225DT. The assembly is viewed from engine side. 1. 2. 3. 4. 5. 7. 10. 11.
Pump assy. Supply line "C'ring Pressure line "0" ring Key Washer Nut
13. 14. 15. 16. 17. 18. 19.
Driven pump gear Gasket Drive housing Gasket Snap ring Drive gear Spacer
156. SYSTEM PRESSURE. Hydraulic system pressure should be 9.8 MPa (1420 psi). To check pressure, install a suitable pressure gage in plug port (P-Fig. 143) on top of control valve. Temporarily loosen transport stop (U-Fig. 133). Run engine at about half throttle and move hand lever to raising position; rockshaft should raise and gage pressure should rise to specified relief pressure. Hold hand lever in RAISE position for ten seconds. Gage pressure should hold steady; a substantial drop in pressure would indicate a worn pump or serious pressure leak. If a pressure gage is not available, lifting capacity at tip of lower links should be 855 kg (1885 pounds). Normal lifting speed to transport position at full throttle is approximately 1% seconds. A low or high relief pressure can be corrected by adding or removing shims (15-Fig. 144) as required. One 0.5 mm shim will change relief pressure about 483 kPa (70 psi). DO NOT hold relief valve open longer than 15 seconds when testing pressure. Reset transport stop (U-Fig. 133) after pressure has been checked.
(L-Fig. 134) is too long, rockshaft will not fully raise. If link is too short, ram piston will bottom before control valve returns to neutral and relief valve will open. To adjust linkage, proceed as follows: With nothing attached to lower links and engine running at slow idle speed, move control lever to fully raised position. Lift arms should raise and engine should not pull down. Loosen locknut and turn turnbuckie on feedback link (L) to shorten link until relief valve opens and engine labors. Back turnbuckie up (lengthen link) until relief valve closes; lengthen link an additional turn and lock in place by tightening locknut. 158. SYSTEM PRESSURE. Hydraulic system pressure should be 13.731 MPa (1990 psi). To check pressure, install a suitable pressure gage in plug port (P-Fig. 146) on top of control valve. Shorten feedback link (L-Fig. 134) three full turns. Run engine at about half throttle and move hand lever to transport position; rockshaft should raise and gage pressure should rise to specified relief pressure. Pressure should hold steady without dropping for ten seconds; a substantial drop in pressure would indicate a worn pump or serious pressure leak. If a pressure gage is not available, lifting capacity at tip ot lower links should be 1200 kg (2650 pounds).
Model L260
Fig. 135-On Modeis L175, L225 and L225DT, hydruaiic system pump is mounted on right side of cylinder biock as shown.
157. FEEDBACK LINKAGE. Auto matic height control feedback linkage should be adjusted to return control valve to neutral JUST BEFORE ram cylinder reaches end of its stroke. If link
Fig.
138-instailed view of front mounted hydrauiic pump used on Modei L210.
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