LK Repair Manual LK36-LK40-LK45 LK50-LK55-LK60
GENERAL PUMP INDEX 1. 2. A member of the Interpump Group LK SERIES INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 3 REPAIR INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 2.1 Repair of the Mechanical Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 2.1.1 Dismantling the Mechanical Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL PUMP A member of the Interpump Group 1. INTRODUCTION LK SERIES This manual contains the instructions for repairing LK Series pumps, and must be carefully read and understood before performing any repair intervention on the pump. Correct use and adequate maintenance is fundamental for the pump’s regular operation and long wear. General Pump declines any responsibility for damage caused by the misuse or the non-observance of the instructions described in this manual. 2. REPAIR INSTRUCTIONS 2.
GENERAL PUMP A member of the Interpump Group 2.1.1 Dismantling the Mechanical Parts The correct sequence is the following: LK SERIES Completely drain the oil of oil, as indicated in 2.1. Remove the valve lifters from the head and the head from the pump casing as shown in 2.2.1 (from fig. 103 to fig. 105). Detach the upper inspection cover and the lower inspection cover by unscrewing the 4 attachment screws, as shown in point 2.2.3 (fig. 129 and fig. 140).
GENERAL PUMP A member of the Interpump Group LK SERIES Take out the radial seal ring, (pos. 1, fig. 5) and the outside O-ring (pos.1, fig 6). Remove the lug from the PTO shaft (pos. 1, fig. 7) Unscrew the attachment screws from the shaft end cover (pos. 1, fig. 8) and slip the cover off the PTO shaft.
GENERAL PUMP A member of the Interpump Group LK SERIES Unscrew the crankcase cover attachment screws (pos. 1, fig. 9) and remove it. Slip off the O-ring and replace it if necessary. Now remove the two bearing covers by unscrewing the screws (pos. 1, fig10). To help with their removal, use 2 M8 grub screws or screws (pos. 1, fig 11) as extractors. Slip off the O-ring and replace if necessary. Insert a shim under the shank of the central connecting rod, to stop the rotation of the crankshaft (pos.
GENERAL PUMP A member of the Interpump Group LK SERIES Unscrew and take out the bushing locking flange attachment screws, from both sides (pos. 1, fig. 13). The bushing locking flanges must be left in position (pos. 1, fig. 14). On one side, screw a ferrule (type SKF KM20) onto the pressure bushing (pos. 1, fig. 15), and then unblock the bushing using a striking hammer (pos. 1, fig 16), but do not remove it. Repeat the operation on the other side.
GENERAL PUMP A member of the Interpump Group Unscrew the connecting rod screws (pos.1, fig. 17). LK SERIES Dismantle the small ends of the connecting rods with the half-bearings. During the operation take particular care to note the order in which the parts are removed The connecting rod small ends and the big end halves must be reassembled in exactly the same order and pairings in which they were dismantled. To prevent any errors, small ends and big end halves are numbered on one side (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group Take out both of the pressure bushings (pos. 1, fig. 20). LK SERIES Separate the bushing locking flange from the pressure bushing (pos. 1, fig. 21). Unscrew the screws of the two bearing support covers (pos. 1, fig. 22).
GENERAL PUMP A member of the Interpump Group LK SERIES Apply an M16 threaded pin to one end of the crankshaft (pos. 1, fig. 23) and, while keeping it raised, take out the bearing support cover complete with bearing and O-ring (pos. 1, fig. 24). To help with their removal, use 2 M10 grub screws or screws (pos. 2, fig. 23) as extractors. Repeat the operation on the other side Lay the crankshaft on the bottom of the crankcase.
GENERAL PUMP A member of the Interpump Group LK SERIES Take out the radial seal ring (pos. 1, fig. 28) and the outside O-ring (pos. 1, fig. 29) and the lubrication hole O-ring (pos. 1, fig. 30) Roll back the three connecting rods as far as possible (until they touch the crankshaft). Using a striking hammer or mallet (pos. 1, fig. 31), take out the PTO crankshaft from either one of the two sides (pos. 1, fig. 32).
GENERAL PUMP A member of the Interpump Group LK SERIES Slip the internal bearing rings off the PTO shaft (pos. 1, fig. 33) and also slip off the two internal bearing spacers (pos. 2, fig. 33). The internal and external bearing rings must be reassembled in exactly the same order and pairings in which they were dismantled. Using a sufficiently long bar (pos. 1, fig. 34) and a striking hammer, take the bearing rings out of the pump casing (pos. 1, fig. 35), along with the external spacer (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES Advance the big end halves in the direction of the hydraulic part and lock them in place using the special tool (p/n F27566200) (pos. 1, fig. 38). Move the crankshaft from the lower part of the casing (pos. 1, fig. 39). Proceed to unscrew the screws of the device (p/n) F2756620) to unlock the connecting rods (pos. 1, fig. 40) and then take out the connecting rod/piston head assemblies from the rear opening of the casing (pos. 1, fig. 41).
GENERAL PUMP A member of the Interpump Group LK SERIES Couple the big end halves to the small ends that were previously dismantled, with reference to their numbering scheme (pos. 1, fig. 42). Remove the two pin-locking Seeger rings using the correct tool (pos. 1, fig. 43).
GENERAL PUMP A member of the Interpump Group LK SERIES Slip out the pin (pos. 1, fig 44) and take out the connecting rod (pos. 1, fig. 45). To separate the stem from the piston head, it is necessary to unscrew the hexagonal-head M10 screw using a no. 17 socket wrench (pos. 1, fig. 46). Complete the disassembly of the mechanical parts by removing the oil level lights and the eyebolts. 2.1.2 Assembling the Mechanical Parts Proceed with the assembly, following the reverse of the procedure shown in 2.2.
GENERAL PUMP A member of the Interpump Group LK SERIES Connect the stem to the piston head. Insert the Ø 5 roll pin in the hole on the piston head (pos. 1, fig. 48) and connect the stem to the piston head using a M10x35 screw (pos. 1, fig 49). Place the stem in a vice, closing the teeth of the vice on the two flat areas, and proceed with setting, using a torque wrench (pos. 1, fig. 50) as shown in section 3, “Screw tightening settings”. Insert the connecting rod into the piston head (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES The crankcase must be inserted into the casing so that the teeth on the ring bevel gears are oriented as shown in fig. 51. Pre-assemble the PTO shaft: Onto the PTO shaft, slip on the 2 internal rings of the bearings (one per side) (pos. 1, fig. 52). The internal and external bearing rings must be reassembled in exactly the same order and pairings in which they were dismantled.
GENERAL PUMP A member of the Interpump Group LK SERIES Remove the device for locking the connecting rods (p/n F27566200) (pos. 1, fig 40) and roll back the connecting rods until they tough the crankshaft. Insert the pre-assembled PTO shaft into the casing (pos. 1, fig. 55). Insert it from the other side to the side where the external bearing ring and the bearing lubrication bushing were inserted. The PTO shaft must be inserted into the casing so that the teeth are oriented as shown in fig. 55.
GENERAL PUMP A member of the Interpump Group LK SERIES At both sides, insert the internal bearing spacers (pos. 1, fig. 59) and the external bearing spacers (pos. 1, fig. 60). Insert the internal ring (pos. 1, fig. 61) and external ring (pos. 1, fig. 62) of a bearing from one side of the pump only.
GENERAL PUMP A member of the Interpump Group LK SERIES Pre-assemble the left and right PTO covers: Insert the radial seal ring into the PTO bearing cover using the correct tool (F27539500) (pos. 1, fig. 63). Before proceeding with the assembly of the radial seal ring, verify the condition of the seal lip. If it is necessary to replace it, position the new ring as shown in fig. 64.
GENERAL PUMP A member of the Interpump Group LK SERIES Mount one of the PTO bearing covers (left or right) on the pump casing (pos. 1, fig. 67) and attach it with four M8X30 screws (pos. 1, fig. 68). Be careful of the direction of assembly of cover. The lubrication hole in the cover must correspond to the hole in the casing. Repeat the operations on the other side: Insert the internal ring (pos. 1, fig. 61) and external ring (pos. 1, fig. 62) of the second bearing.
GENERAL PUMP A member of the Interpump Group LK SERIES The bearing in fig. 70 has a conical internal ring. Verify that the conicity is from the out side to the inside to allow the subsequent insertion of the bushing. Apply the O-ring to the outside of the bearing support cover (pos. 1, fig. 71). Repeat the operation with the other cover. Lock the three connecting rod assemblies, using the special tool (F27566200) (pos. 1, fig 40).
GENERAL PUMP A member of the Interpump Group LK SERIES Fasten the bearing support covers with 6 M10X30 screws (pos. 1, fig. 74). Tighten the screws with a torque wrench, as shown in section 3. “Screw Tightening Settings”. Partly insert the two pressure bushings, keeping the crankshaft lifted up by means of the previously mounted M16 pin (pos. 1, fig. 75). Insert the pressure bushing completely onto the crankshaft (pos. 1, fig. 76 and fig. 77) using a mallet or striking hammer and a pad.
GENERAL PUMP A member of the Interpump Group LK SERIES The pressure bushing must be inserted dry (no lubricant). Insert the bushing until the outside (conical) surface perfectly couples with the inside of the bearing. During insertion, make sure that the bearing stays in contact with the crankshaft shoulder. Repeat the operation on the other side. Insert the bushing locking flanges into the conical bushings (pos. 1, fig. 78).
GENERAL PUMP A member of the Interpump Group LK SERIES Insert the upper half-bearings between the connecting rods and the crankshaft (pos. 1, fig. 80) To correctly assemble the half-bearings, make sure that the lug on the half-bearing is positioned in the slot on the big end half (pos. 1, fig. 81). Apply the lower half-bearings to the small ends (pos. 1, fig. 82), making sure that the lugs on the half-bearings are positioned in the slots on the small ends (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES Insert a shim under the shank of the central connecting rod, to stop the rotation of the crankshaft (pos. 1, fig. 84). Measure the distance X indicated in fig. 85 between the conical bushing and the crankshaft bearing. Screw in the M16 screw until there is a reduction in the distance X of between 0.7 mm and 0.8 mm (fig. 86).
GENERAL PUMP A member of the Interpump Group Repeat the operation on the other side. LK SERIES Remove the M16 screw from the crankshaft. Screw the two bushing locking flanges onto the crankshaft using 4 M12X25 screws (pos. 1, fig. 87). Apply LOCTITE 243 to the threads of the M12X25 screws (pos. 1, fig. 87). Tighten the screws with a torque wrench, as shown in section 3, “Screw Tightening Settings”. Remove the anti-rotation shim from under the shank of the central connecting rod.
GENERAL PUMP A member of the Interpump Group LK SERIES Insert the O-ring into the rear cover (pos. 1, fig. 91) and affix it to the casing using 10 M8X20 screws (pos. 1, fig. 92). Tighten the screws with a torque wrench, as shown in section 3 “Screw Tightening Settings”. Mount the radial seal ring onto the oil seal cover (pos. 1, fig. 93) using a pad (F27910900). Position the O-ring (pos. 1, fig. 94) on the seat of the oil seat cover.
GENERAL PUMP A member of the Interpump Group LK SERIES Insert the assembly into the casing and into the seat provided, making sure that the cover completely enters its seat (pos. 1, fig. 95), being careful not to damage the lip of the radial seal ring. Screw in the oil seal covers using 2 M6X30 grub screws (pos. 1, fig. 96). Tighten the screws with a torque wrench as shown in section 3, “Screw Tightening Settings”.
GENERAL PUMP A member of the Interpump Group LK SERIES Tighten the screws with a torque wrench, as shown in section 3, “Screw Tightening Settings”. Mount the shaft end cover and affix it to the casing using 3 M8X20 screws (pos. 1, fig. 101). Tighten the screws with a torque wrench, as shown in section 3 “Screw Tightening Settings”. Apply the lug to the PTO shaft (pos. 1, fig. 102).
GENERAL PUMP LK SERIES A member of the Interpump Group 2.1.3 Classes of Increase INCREASE TABLE FOR CRANKSHAFT AND CONNECTION ROD HALF-BEARINGS Recovery Classes (mm) 0.25 0.50 Upper half bushing p/n Lower half bushing p/n 90931100 90930100 90931200 90930200 Crank pin grinding measures (mm) Ø 92.75 0/-0.03 Roughness Ra 0.4 Rt 3.5 Ø 92.50 0/-0.03 Roughness Ra 0.4 Rt 3.5 INCREASE TABLE FOR PUMP CASING AND PISTON HEAD Recovery Classes (mm) Piston Head p/n 1.
GENERAL PUMP A member of the Interpump Group LK SERIES Apply two supports with G2” threading to the outlet connections of the head (pos. 1, fig. 104) and then unscrew the 8 M16X150 screws (pos. 1, fig. 105). Take care to not subject the plungers to knocks or bumps when taking them out of the head. Unscrew and remove the 8 M16X55 screws of the valve cover (pos. 1, fig. 106) and remove the cover (pos. 1, fig. 107).
GENERAL PUMP A member of the Interpump Group Slide out the spring (pos. 1, fig. 109). LK SERIES Remove the outlet valve assembly by using a slide hammer puller applied to the M10 hole in the valve holder (pos. 1, fig. 110). If it is particularly difficult to remove the outlet valve assembly (e.g. there are build up deposits because the pump has not been used for a long period), use the extractor tool F27516400 (for LK36,40,45) or p/n F27516500 (for LK50, 55, 60).
GENERAL PUMP A member of the Interpump Group LK SERIES Remove the inlet valve assembly by using a slide hammer puller applied to the M10 hole in the valve holder (pos. 1, fig. 112). If it is particularly difficult to remove the outlet valve assembly (e.g. there are build up deposits because the pump has not been used for a long period), use the extractor tool F27516200 (for LK36,40,45) or p/n 27516300 (for LK50, 55, 60) (pos. 1, figs 113) and use it as shown in the diagram.
GENERAL PUMP A member of the Interpump Group 2.2.2 Assembling the Head - The Valve Assemblies LK SERIES Check the state of wear of the various components very carefully and replace them if necessary. At each inspection of the valves, replace all the O-rings, both for the valve assemblies and for the valve plugs. Before repositioning the valve assemblies, clean their seats in the head, located by the arrows (pos. 1, fig. 115), and then dry these seats completely.
GENERAL PUMP A member of the Interpump Group LK SERIES Proceed with the insertion of the valve assemblies (inlet and outlet) into the head, taking care to follow the correct insertion sequence of the O-rings and the anti-extrusion rings. The correct assembly sequence for the valve assemblies in the head is as follows: Insert the anti-extrusion ring, exploded Position #4, from Owner’s Manual, (pos. 4, fig. 119). Insert the O-ring, exploded position #5, from Owner’s Manual, (pos. 1, fig. 120).
GENERAL PUMP A member of the Interpump Group LK SERIES Mount the O-ring, exploded position #5, from Owner’s Manual, (pos. 1, fig. 123) and the anti-extrusion ring, exploded position #15 (pos. 2, fig. 123), onto the outlet valve seat. Insert the outlet valve assembly (pos. 1, fig. 124). The valve assembly must be inserted all the way in, as shown in pos. 1, fig. 125. Insert the anti-extrusion ring, exploded position #16 (pos. 1, fig. 126).
GENERAL PUMP A member of the Interpump Group Insert the O-ring, exploded position #17 (pos. 1, fig. 127) LK SERIES Be very careful when inserting the O-ring indicated in pos. 1, fig. 128. We recommend using the special tool, p/n F27516000 (for LK36, 40, 45) or p/n F27516100 (for LK50, 55, 60), to prevent the O-ring from being cut during insertion. Insert the valve seat ring (pos. 1, fig. 129 and the spring (pos. 1, fig. 130).
GENERAL PUMP A member of the Interpump Group LK SERIES Mount the O-ring, exploded position #17 (pos. 1, fig. 131) and the anti-extrusion ring, exploded position #21 (pos. 2, fig 131), onto the outlet valve plug. Insert the valve plug, complete with O-ring and anti-extrusion ring. After insertion of the valve assemblies and the valve plugs is complete, replace the valve cover (pos. 1, fig. 132) and screw in the 8 M16X55 screws (pos. 1, fig. 133). Attach the head to the pump casing (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES Proceed to tighten the M16X150 screws with a torque wrench, as shown in section 3 “Screw Tightening Settings”. Tighten the 8 M16X150 screws, beginning by cross-tightening the 4 inside screws (see fig. 135) and then moving on to the 4 outside screws, again, cross-tightening them. Tighten the M16X55 screws of the cover with a torque wrench, as shown in section 3, “Screw Tightening Settings”. Insert the valve lifters (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES 2.2.3 Dismantling the Plungers-Supports-Seals Assembly The plunger assembly requires regular inspection as indicated in the preventive maintenance table in the Owner’s Manual. Operations are limited to a visual check for any draining from the hole in the lower cover. If there are anomalies/oscillations in the outlet pressure gauge, or drips from the drain hole, then the seal packing must be checked and, if necessary, replaced.
GENERAL PUMP A member of the Interpump Group LK SERIES Manually rotate the shaft to bring the 3 plungers into the top dead center position. Insert the plastic buffer (p/n F27516600) between the plunger head and the plunger (pos. 1, fig. 141). By rotating the shaft, advance the plunger head so that the plastic buffer advances in its turn and expels the gasket support and the entire plunger assembly (pos. 1, fig. 142). Remove the gasket support assembly and the plastic buffer.
GENERAL PUMP A member of the Interpump Group LK SERIES Separate the gasket support from the liner by using a compass spanner with Ø 5 round ends, available on the market, (pos. 1, fig. 145) and unscrew the support until it is completely removed (pos. 1, fig. 146). Manually remove the head rings, the pressure gaskets and the restop rings (pos. 1, fig. 147). To remove the low pressure gasket, use a feeler gauge or other tool that does not damage the gasket support seat (pos. 1, fig. 148).
GENERAL PUMP A member of the Interpump Group LK SERIES 2.2.4 Assembling the Plungers - Supports - Seals Assembly Proceed with the reassembly, following the reverse of the disassembly procedure shown in 2.2.3. Replace the pressure gaskets, moistening the lips with silicone grease (without covering the gaskets), and taking great care not to damage them while inserting them into the liner. At every disassembly, the pressure gaskets must always be replaced, together with all the O-rings.
GENERAL PUMP A member of the Interpump Group LK SERIES Screw the gasket support to the liner (pos. 1, fig. 154) and tighten using a compass spanner with Ø 5 round ends, available on the market (pos. 1, fig. 155), until the support abuts the liner. Place the 14x2 O-ring on its seat on the plunger attachment screw (pos. 1, fig. 156). Place the plungers on their respective holders (pos. 1, fig. 157) and fix them in place as in pos. 1, fig. 158.
GENERAL PUMP A member of the Interpump Group LK SERIES Tighten the screws with a torque wrench, as shown in section 3, “Screw Tightening Settings”. Insert the previously assembled liner/gasket support block (complete with its two O-rings, until it is snugly in place (pos. 1, fig. 159). Make sure that the liner/support block goes all the way in and is correctly positioned on its seat (pos. 1, fig. 160). Place the frontal O-ring on the liner (pos. 1, fig.
GENERAL PUMP A member of the Interpump Group LK SERIES Insert the O-rings on the inspection covers (pos. 1, fig. 163) and mount the covers using 4 M6X14 screws (pos. 1, fig. 164).
GENERAL PUMP LK SERIES A member of the Interpump Group 3. SCREW CALIBRATION Screws are to be fastened exclusively using a torque wrench. Description M8x20 screw, casing cover G1/2x13 plug, casing M8x30 screw, PTO bearing cover M8x20 screw, shaft end cover M10x30 screw, bearing support cover M6x14 screw, upper & lower covers Exploded View Position Fastening Fastening (From Owner’s Manual) Ft. Lbs. Nm 42 18.44 25 85 18.44 25 66 29.5 42 18.44 70 7.38 57 33.
GENERAL PUMP 4. REPAIR TOOLS A member of the Interpump Group LK SERIES Pump maintenance may be carried out using simple tools for assembling and disassembling components. The following tools are available: For Assembly: • • • • Plunger head radial seal ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p/n PTO shaft radial seal ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p/n O-ring, outlet valve seat (LK36, LK40, LK45) . . . . . . . . . . . .
GENERAL PUMP MAINTENANCE LOG A member of the Interpump Group LK SERIES HOURS & DATE OIL CHANGE GREASE PACKING REPLACEMENT PLUNGER REPLACEMENT VALVE REPLACEMENT GP Companies, Inc. 1174 Northland Drive Mendota Heights, MN 55120 Phone:651.686.2199 Fax: 800.535.1745 www.generalpump.com email: sales@gpcompanies.com Ref 300772 Rev.
