Pratissoli 28A, Repair Manual

Page 1: ...KT24A 28A 30A 32A 36A 40A Repair Manual General Pump is a member of the Interpump Group 8 Ref 300943 Rev A 03 14 KT24A KT28A KT30A KT32A KT36A KT40A ...

Page 2: ...uction Classes Page 8 2 1 4 Disassembly Reassembly of Bearings and Shims Page 8 2 2 Repairing Hydraulic Parts Page 11 2 2 1 Dismantling the Head Valve Units Page 11 2 2 2 Reassembling the Head Valve Units Page 14 2 2 3 Dismantling the Head Seals Page 15 2 2 4 Dismantling the Piston Unit Page 17 2 2 4 Assembling the Head Seals Piston Unit Page 18 3 SCREW CALIBRATION Page 19 4 REPLACING THE CON ROD ...

Page 3: ...e or the non observance of the instructions described in this manual 2 REPAIR INSTRUCTIONS 2 1 Repairing Mechanical Parts Mechanical parts repair must be performed after removal of oil from the casing To drain the oil remove the oil dipstick 1 fig 1 and then the draining plug 2 fig 1 The oil must be placed in a suitable container and disposed of in special centers It absolutely must not be discard...

Page 4: ...he connecting rod cap as follows unscrew the cap fixing screws remove the con rod caps with their lower half bearings fig 2 paying atention to the numbered sequence during disassembly To avoid possible errors caps and con ro shanks have been numbered on one side 1 fig 2 a Push the piston guides forward with their con rods to facilitate side extraction of the pump as indicated in fig 4 Ref 300943 R...

Page 5: ...ove the pump shaft seal rings using common tools Remove the piston guide seal rings as described below Use the extractor p n F26019400 1 fig 5 and the gripper p n F27503800 2 fig 5 Insert the gripper as far as possible onto the seal ring with the aid of a hammer fig 5 a subsequently screwing the extractor to the gripper and use the extractor hammer fig 5 b until the ring to be replaced is removed ...

Page 6: ... their respective seats in the con rod and cap After having checked that the casing is clean proceed with assembly of the mechanical part as described below Assemble the upper and lower half bearings in their seats in the con rods and caps If replacement is necessary position the new ring using tool p n F27904500 as incicated in fig 7 If the pump shaft shows diametrical wear in the area of contact...

Page 7: ...rnatively ensure 1 Pre tightening torque 7 11 Ft Lbs 10 15 Nm 2 Tightening torque 22 Ft Lbs 30 Nm Ref 300943 Rev A 03 14 After having completed tightening operations check that the con rod head has a side clearance in both directions Assemble the new piston guide seal ring with the relative seats on the pump casing fig 11 following the procedure described Using tool p n F27904200 composed of a tap...

Page 8: ...ON ROD HALF BEARINGS Recovery Classes mm Part Number Half bearing Upper Part Number Half bearing Lower Correction on the Shaft Pin Diameter mm 0 25 F90922100 F90922400 Ø39 75 0 0 02 Ra 0 4 Rt 3 5 0 50 F90922200 F90922500 Ø39 50 0 0 02 Ra 0 4 Rt 3 5 2 1 4 Disassembly Reassembly of Bearing and Shims The type of bearings taper roller ensures the absence of axial clearance on the crankshaft The shims ...

Page 9: ... first positioning phase as indicated in fig 8 and the screws provide for final fastening Shaft rotation torque with the con rod connected should not exceed 6 Ft Lb 8 Nm A Disassembly Reassembly of the crankshaft with bearings replacement After removing the side covers as described above remove the outer ring nut on the bearings from its seat on the covers using an appropriate extractor as shown i...

Page 10: ...lty during shaft rotation will soon be experienced At this point halt the forward movement of the cover and loosen the fixing screws completely With the aid of a thickness gauge measure the clearance between the side cover and pump casing fig 4 Detected Measurement Shim Type Pieces From 0 05 to 0 10 From 0 11 to 0 20 0 1 1 From 0 21 to 0 30 0 1 2 From 0 31 to 0 35 0 25 1 From 0 36 to 0 45 0 35 1 F...

Page 11: ...units are assembled vertically inside the head Operate as follows to extract them Unscrew the 8 M14x40 suction valve cover fastening screws and the 8 m12x35 outlet valve cover fastening screws fig 16 and 16a using the extractor hammer p n F26019400 combined with tool F27726200 extract The KT24A 28A 30A 32A suction and outlet valve units and KT36A or 40A inlet valve units using a simple tool as ind...

Page 12: ...e units can be carried out screwing in a sufficiently long M10 screw which can move the valve plate and remove the valve guide from the seat 1 fig 20 If the threaded holes should not be present on the valve guides dismantling can be easily carried out by leveraging with simple tools fig 21 Page 12 Ref 300943 Rev A 03 14 ...

Page 13: ...seats remain stuck on the head for example scaling due to prolonged pump activity operate as follows Suction and outlet valves For KT24A 28A 30A 32A use tools F26019400 and F27513700 fig 22 Suction valves For KT36A and 40A use tools F26019400 F27516900 fig 22 Outlet valves For KT36A and 40A use tools F26019400 and F27513700 fig 22 ...

Page 14: ... replace if necessary and at the intervals indicated in the Preventative Maintenance table in chapter 11 of the use and maintenance manual At every valve inspection replace all O rings and all anti extrusion rings both in the valve groups and on the valve plugs Before repositioning the valve unit thoroughly clean and dry the relative seats in the head as indicated in fig 25 Ref 300943 Rev A 03 14 ...

Page 15: ...e down to end stroke in the head housing Then apply the valve covers and calibrate the respective M14x40 screws suction valve covers and M12x35 outlet valve cover screws For the values of the torques and tightening sequences follow the instructions in chapter 3 2 2 3 Dismantling the Head Seals Replacement of the seals is necessary from the moment you begin to detect water leaks from the drainage h...

Page 16: ... Extract the high pressure seals from the head and the low pressure ones from the support using simple tools as indicated in fig 27 being careful not to damage the respective housings Pay attention to the order of seal pack disassembly as indicated in fig 28 composed of 1 Head ring 2 HP seal 3 Restop ring 4 Seals support 5 LP seal 6 Seal ring 7 O ring ...

Page 17: ...ce if necessary At every disassembly all o rings on the piston unit must be replaced Ref 300943 Rev A 03 14 2 2 4 Dismantling the Piston Unit The piston unit does not require any routine maintenance Maintenance is limited to visual checks only To extract piston units loosen the M7x1 piston fixing screws as indicated in fig 29 ...

Page 18: ...mbly of HP seals in their housing on the head without causing any damage to lip seals use suitable tools according to the pump diameters as indicated in chapter 4 D Replace the piston tightening the screws with a torque wrench respecting the tightening torque values ad indicate in chapter 3 E Replace the head as follows 1 Position the seal support in the respective seats on the casing 2 Using two ...

Page 19: ... 132 8 180 Valve Cover Fixing Screw Suction 45 88 5 120 Head Fixing Screw 55 30 40 2nd PTO Flange Fixing Screw 96 107 145 The con rod cap fixing screws must be tightened at the same time respecting the phases indicated on page 7 The head fixing screws exploded position 55 must be tightened with a torque wrench respecting the sequence shown in the diagram in fig 31 The valve cover fixing screws exp...

Page 20: ...ing proceed as follows When removing the worn bushing take great care not to damage or scratch the seat on the con rod Perform cold press fitting of the new bushing During the operation ensure that the lubrication hole coincides with the corresponding hole on the con rod the cutting junction is directed as shown in fig 32 Then perform mechanical processing The dimensions and tolerances shown in fi...

Page 21: ...5 F26406300 F27465700 Seal bushing Ø 44 HP alternative seal ring Ø 32x44x6 3 F27722000 F27385400 Seal bushing Ø 48 HP alternative seal ring Ø 36x48x6 3 5 F26406300 F27465800 Seal bushing Ø 55 HP alternative seal ring Ø 40x55x7 5 4 5 F27718100 F27356300 Pump shaft oil seal F27904500 Piston guide oil seal F27904200 Head F27726000 For Disassembling Part Tool Part Number Pump suction valve KT24A KT26A...

Page 22: ...age 22 5 MAINTENANCE LOG OIL CHANGE GREASE PACKING REPLACEMENT PLUNGER REPLACEMENT VALVE REPLACEMENT HOURS DATE 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 300943 Rev A 03 14 ...