TUSKER DIGGER MK. 4 THWAITES LTD

TUSKER DIGGER MK. 4 THWAITES LTD The copyright in this publication and its illustrations are vested in Thwaites Ltd. and action will be taken where unauthorised copies are made. WHEN ORDERING SPARES PLEASE QUOTE MACHINE SERIAL NUMBER... SPARES FAX: (01926) 450458 T0089

Thwaites THWAITES ENGINEERING COMPANY LIMITED LEAMINGTON SPA ENGLAND Digger Mk 4

Thwaites Digger Mk 4 OPERATOR INSTRUCTIONS FOR THWAITES DIGGER DUMPER The Thwaites Digger Dumper is a very powerful excavator for its size and extremly simple to operate. Read carefully the following operation and maintenance instructions, which will help to familarise oneself with the machine. 1. It is important to remember the sequence of controls and what each lever does. The diagram below shows this when operator is in seated position. Dipper Slew Boom Bucket Away Right Lower Open Towards Left Raise Close Make sure first that this is in the most comfortable position for you. 2. LOWER STABILIZERS: It is always best to drop the right hand stabilizer first. Slew boom to right approximately 45 from centre with the Dipper extended halfway and bucket almost closed, it is then only a question of pushing the boom lever forward raising the driving wheel off the ground. With the wheel approximately 1/3rd of a metre off the ground, kick the plunger release of the stabilizer, which will then drop. Now BEFORE lifting the boom and slewing to lower the left stabilizer down, make absolutely sure the plunger has gone 100% home in one of the locating holes. THIS IS MOST IMPORTANT. 3. PRACTICE PROCEDURE: With the Digger Dumper now level and raised ready for digging, we come to the most important section of all, CONTROL: place both hands on the two outside levers, Dipper and Bucket. The engine should be set for ¼ to ½ speed (it is very seldom more than ¾ throttle is ever required). With the palm of your right hand resting on the bucket lever using thumb and forefinger only, push the boom lever forward, this is best done with bucket and dipper fully extended. Absolute control must be mastered of the boom to produce a quick smooth raise and lower action. Control of the levers actuating the bucket slew and dipper will be found straightforward once boom control is mastered. DO NOT cross hands over during the digging operation. The right hand must work the bucket and boom, the left hand the dipper and slew. 4. IMPORTANT THE SECRET of all efficient high output digging is to TAKE A LONG and THIN SLICE AT A TIME and always lift out with a full bucket even if this means taking another bite. 5. INITIAL PENETRATION is always the most difficult but once a depth of about 1/3rd of a metre has been reached, digging becomes easier. 6. DIGGING PROCEDURE: Extend dipper to ¾ of its maximum reach, bucket ¼ open, lower boom, bucket teeth just biting the surface with the throttle set at half speed. Pull back the dipper lever and the bucket will inbed itself into the ground. The pressure release valve will then blow off (a distinct hissing noise) as the dipper stops. Keeping the dipper lever back, bring the boom lever towards you VERY gently. As the dipper comes to the end of its travel, bring the bucket lever towards you, all things being equal the result should be a full bucket. This is only intended as a guide and practice is the only way that will make a fine excavator driver. 7. MOVING THE DIGGER DUMPER BACKWARDS: when trenching instead of driving, make absolutely sure your rear wheels are straight. Lift front end of the machine with the aid of boom and dipper until both stabilizers are clear of ground. By pushing the dipper lever forward (WITH CAUTION until fully experienced) the machine will move back. This is best practised on smooth ground first. 8. RAISING STABILIZERS: You will find it necessary to get over the top of these and lift in a quick sharp upward movement. It is no use trying to remain seated while attempting this. Changing Digger to Dumper The first thing to be done is find a reasonably flat piece of ground. Concrete is best but that cannot always be found. One has to use a little common sense when placing the Digger stand and a fairly level surface can usually be located somewhere on site. The procedure is as follows: 1. Drive Digger Dumper on to stand, this has to be done with plenty of gusto. It is impossible to drive too far owing to the stops fitted. It is essential that the dumper sits 100% squarely on the stand, this is MOST IMPORTANT. For this operation the back hoe must be slewed into the dead ahead position. With the machine now on its stand, lower the boom until the lowest part of the bucket is not less than 18 above the ground and not more than 24.

Thwaites Digger Mk 4 2. Stop engine (using pump rack and NOT decompressor). Remove spring clips from the 2-1 tapered pins located on either side of machine behind hydraulic tank, noting that the tapered end faces outwards. Remove both pins, placing them in a safe place with the spring clips. Now making sure the throttle lever on Digger is fully closed (backwards when sitting on Digger). At the point where the linkage joins the throttle mechanism on the Petter engine, grip and lift upwards pushing linkage forward and out of the way so that it rests in the vertical position. Now all that remains is to disconnect the hydraulic drive, this is done by grasping the male portion of the coupling (from the nearside of machine) then twisting it towards you as far as it will go and at the same time pull away from the engine it will then separate. These three operations will be much simpler if a liberal coating of oil is applied to the above mentioned parts namely, throttle linkage, hydraulic quick release coupling and the two tapered pins. They will of course ease up with use. Fig 1. Remove both pins and stow clips Fig 2. Lift the link clear Fig 3. Lift flap and turn coupling as shown 3. Restart engine and reverse dumper away from digger unit. It is a good idea before doing this to check that EVERYTHING has been properly disconnected. As soon as you have done this the whole unit will tip forward on the stand, the bucket resting on the ground. At this stage, should the digger unit not be required for a day or so, it is a good idea to place a support under the hydraulic tank. This stops the back end of the unit dropping down should anyone touch the boom lever by mistake. (Safeguard for children). 4. With the digger dumper skip in the near upright position, held there by the special skip prop, drive the dumper up to the skip leaving the handbrake OFF. Connect up skip straps by pulling or pushing on the driving wheels of dumper to reduce or increase cleanance. You will find the connecting up procedure very simple. Attach both check chains. Changing Dumper to Digger 1. Reverse procedure (4) remembering not to lose clevis pins from check chains. 2. Drive machine SQUARELY onto stand as far as it will go. You will note that the two hooks on the front end of the digger unit hit the front chassis cross member (channel) of the dumper, this is correct. Be very careful when driving in to make sure that the back end of the digger is high enough to enable the hydraulic drive prop shaft to clear the front chassis member. This is MOST IMPORTANT as damage can be done to hydraulic pump if the drive shaft is hit. 3. When you are satisfied that the dumper is absolutely square to the digger unit, AND NOT UNTIL THEN, push the lever second from the right (when the digger driving position) FORWARD. This will drop the back end. It is then only a question of driving the machine forward about 6-9, in any case as far as it will go. 4. The 1 holes on digger unit and dumper will now be level with each other, replace tapered pins (spring clip on the outside). Connect hydraulic drive and throttle linkage, restart engine, raise boom, close dipper. The machine is now ready to commence digging. Should you have any difficulty in changing digger to dumper or vice versa please contact our distributor in your area or the Sales Department of Thwaites Engineering Co., Ltd., Leamington Spa. Tel No. Leamington 422471.

Thwaites Digger Mk 4 MAINTENANCE INSTRUCTIONS It is extremely important that the machine be kept clean, if cleaned regularly it facilitates easy greasing and maintenance. NO adjustments should be required to the Hydraulics as these are pre-set at the works, should you feel that the Hydraulics are not working correctly, do not attempt to alter them yourself, contact your nearest THWAITES agent or THWAITES ENGINEERING CO. LTD., Service Department. All Hydraulic Pipe Connections should be checked periodically to ensure that the Hydraulic Oil is not leaking. DO NOT allow the machine to run without sufficient Hydraulic Oil in the tank. If the oil level is allowed to drop below the filter, damage will be caused to the Pump. THE CORRECT GRADE OF HYDRAULIC OIL IS: MOBIL D.T.E.LIGHT Maintenance Daily Grease Machine. Check Oil in Hydraulic Tank. Oil all Working Parts. Weekly Check all Bolts for tightness. Inspect All Hydraulic Connections for Leaks. Tighten if necessary. Monthly Remove Hydraulic Filter, clean, replace cartridge. Greasing points are as follows: Propshaft King Post Rams Top & Bottom Leg Locking Pins Slewing Arms Bucket Linkage Feet Pivot Boom Top & Bottom Pin Bucket Swivel Pin

Thwaites Digger Mk 4 INDEX PAGE CONTENTS Operation & Maintenance Instructions 1-2 Digger Chassis & Fittings 3-4 Boom, Rams & Bucket 5-6 Boom Ram & Mounting Assy. 7-8 Hyd. Control Valve & Oil Filter 9 Hyd. Control Valve with Control Fittings 10 Oil Circuit 11-12 Oil Pump Assembly (Up to m/c no. 4-49887 - Unit no. 5-1621) & Oil Pump - Drive Shaft Assembly 13 Oil Pump Assembly (Up to m/c no. 4-50014 - Unit no. 6-1622) (Replaced Oil Pump illustrated on Page 11)

DIGGER CHASSIS AND FITTINGS Thwaites Digger Mk 4 1

DIGGER CHASSIS AND FITTINGS Thwaites Digger Mk 4 Item Part No. Qty. Description Item Part No. Qty. Description 1 T6458 1 Connecting Link 2 T6197 1 Clevis Pin 3 T6701 4 Washer 4 T6702 5 Split Pin 5 T6703 1 Bolt 6 T6701 1 Washer 7 T6335 1 Spring 8 T6334 1 Friction Pad 9 T6344 1 Hand Throttle Lever 10 T8210 1 Hyd. Tank Filler Cap 11 T5693 1 Hyd. Tank Filler Strainer 12 T6704 6 Bolt 13 T6705 6 Spring Washer 14 T5987 1 Plate for Filler Cap 15 T5988 1 Gasket (Filler Cap Plate to Tank) 16 T6196 1 Hydraulic Tank 17 T6706 6 Bolt 18 T6707 4 Washer 19 T6453 4 Rubber Spacer 20 T6708 6 Nyloc Nut 21 T6050 1 Tank Breather c/w T9351 Element 22 T10380 1 Seat Frame 23 T10382 1 Seat Back 24 T10381 1 Seat Cushion T10663 1 Seat Assembly 25 T5112 1 Seat Mounting Pin 26 T6709 2 Split Pin 27 T6203 1 Prop Shaft Cover 28 T6710 2 Split Pin 29 T6693 4 Jubilee Clip 30 T6062 1 Rubber Elbow 31 T6001 1 Union 32 T7953 4 Copper Washer 33 T6048 1 Micronic Filter 34 T6912 1 Banjo 35 T5972 1 Banjo Bolt 36 T6911 1 Rubber Hose 37 T6047 1 Suction Filter 38 T6049 1 Drain Plug 39 T6202 2 Connecting Pin 40 T6075 4 Lynch Pin 41 T8443 1 Digger Chassis 42 T5265 2 Pedal Rubbers 43 T5927 1 Foot Pedal L/H N/S 44 T5926 1 Foot Pedal R/H O/S 45 T5929 2 Link 46 T5928 2 Locking Peg 47 T6187 4 Clevis Pin 48 T5037 2 Spring 49 T6191 16 Stabiliser Leg Roller 50 T6711 16 Washer 51 T6712 16 Nyloc Nut 52 T6713 2 Bolt 53 T6714 6 Bolt 54 T6208 1 Stabiliser Leg L/H 55 T6207 1 Stabiliser Leg R/H 56 T5969 2 Stabiliser Feet 57 T5996 2 Pin 58 T6515 2 Hyd. Ram (Slew Ram) 59 T6070 2 Bush 60 T5670 4 Bush 61 T6224 2 Hinge Pin 62 T6715 2 Split Pin 63 T6716 2 Bolt 64 T6717 2 Nyloc Nut 65 T6248 1 Hyd. Pipe L/H 66 T6880 1 Hyd. Pipe R/H 67 T6864 1 Hyd. Pipe R/H 68 T6870 1 Hyd. Pipe L/H 69 T6879 1 Hyd. Pipe R/H 70 T6247 1 Hyd. Pipe L/H 71 T6205 6 Bolt 72 T6718 8 Nut 73 T6705 12 Spring Washer 74 T6716 4 Bolt 75 T6719 4 Nut 76 T5053 2 Straight Grease Nipple 77 T6493 1 King Pin (Valve Op. Lever) 78 T6707 1 Washer 79 T6449 6 Adaptor 80 T5991 2 Spacer 81 T5275 2 Pin 82 T6745 2 Split Pin 83 T8446 1 Foot Pedal N/S 84 T8445 1 Foot Pedal O/S 85 T8476 2 Locking Peg 86 T6841 2 Nut 87 T6738 2 Spring Washer 88 T6704 2 Set Screw 89 T6756 2 Split Pin 90 T5267 4 Bush 91 T6673 2 Grease Nipple 2

BOOM, RAMS & BUCKET Thwaites Digger Mk 4 3

BOOM, RAMS & BUCKET Thwaites Digger Mk 4 Item Part No. Qty. Description Item Part No. Qty. Description 1 T6516 1 Boom 2 T7229 6 Bush 3 T6536 1 Pin 4 T6076 2 Rubber Buffer 5 T6728 2 Bolt 6 T6728 2 Bolt 7 T6707 4 Washer 8 T6708 3 Nyloc Nut 9 T6620 2 Hyd. Hose 10 T5390 2 Hyd. Hose 11 T6449 4 Adaptor 12 T6508 1 Pipe Clamp 13 T6716 6 Bolt 14 T6705 18 Spring Washer 15 T6718 8 Bolt 16 T6442 2 Pipe Clamp 17 T6507 2 Hyd. Pipe 18 T6506 2 Hyd. Hose 19 T6219 1 Ram Pin 20 T6535 1 Ram Pin 21 T6222 6 Collar 22 T6729 6 Bolt 23 T6730 6 Locknut 24 T6673 3 ¼ BSF St. Grease Nipple 25 T6205 2 Pipe Clip 26 T6624 1 Hyd. Pipe 27 T6625 1 Hyd. Pipe 28 T5061 3 3/8 BSF Angled Grease Nipple 29 T6719 4 Nut 30 T6223 1 Hinge Pin 31 T6515 2 Hyd. Ram 32 T6070 2 Bush 33 T5670 4 Bush 34 T5020 2 ¼ BSF 90 Grease Nipple 35 T6322 1 Hyd. Hose 36 T6057 1 Hyd. Hose 37 T5053 3 3/8 BSF St. Grease Nipple 38 T5747 2 Hyd. Hose 39 T6221 1 Hinge Pin 40 T6155 1 Dipper Arm 41 T7228 2 Bush 42 T6159 1 Arm R/H 43 T6158 1 Arm L/H 44 T6218 2 Hinge Pin 45 T6201 1 Bucket Connecting Link 46 T7231 2 Bush 47 T7230 2 Bush 48 T6461 2 Bucket Pin (superseded by item 52) 49 T6075 2 Spring Lynch Pin 50 T6329 1 12 Bucket T6328 1 18 Bucket T6327 1 24 Bucket 51 T10106 4 Bucket Teeth 52 T8156 2 Pin 53 T6731 4 Bolt 54 T6732 8 Nut 55 T6733 4 c/snk sq. Head Bolt 56 T5596 2 Hyd. Washer 57 T6077 4 Bucket Teeth (superseded by item 51) 58 59 T6316 2 Adaptor 60 T6440 2 Tension Pin 61 T8128 4 Spacer 62 T6436 1 Boom Ram 63 T8276 8 Bolt 64 T8275 8 Nut 65 T10037 4 Bush 4

BOOM RAM & MOUNTING ASSEMBLY Thwaites Digger Mk 4 5

BOOM RAM & MOUNTING ASSEMBLY Thwaites Digger Mk 4 Item Part No. Qty. Description 1 T5939 1 King Post Pin 2 T5816 2 Oil Seal 3 T5073 2 Bearing 4 T6517 1 King Post 5 T5054 1 Nut - King Post 6 T6720 1 Split Pin 7 T6225 4 Pin 8 T6211 1 Slewing Arm L/H 9 T6211 1 Slewing Arm R/H 10 T6673 2 ¼ BSF St. Grease Nipple 11 T6336 2 Bush 12 T6514 1 Pin (Ram to King Post) 13 T6721 4 Split Pin 14 15 T6067 2 Tension Pin 16 T5670 2 Bush 17 T6440 2 Tension Pin 18 T5061 1 3/8 BSF Angle Grease Nipple 19 T6070 1 Bush 20 21 T6687 1 Piston Rod 22+ T6676 1 Wiper Seal 23 T6677 1 Gland Nut 24+ T6678 2 Gland Seal 25+ T6679 1 Gland O Ring 26 T6680 1 Gland Housing 27 T6681 1 Piston Head Retainer 28+ T6682 1 Piston Seal 29+ T6683 1 Piston O Seal 30 T6684 1 Piston Head 31 T6685 1 Piston Nut 32 T6436 1 Boom Ram (complete) 33 T9502 1 Washer T8785+ Seal Kit comprising items 22, 24, 25, 28 & 29. Note: Internal parts of Hyd. Boom Ram as shown are fitted also to Hyd. Ram T6515. 6

HYD. CONTROL VALVE & OIL FILTER Thwaites Digger Mk 4 7

HYD. CONTROL VALVE & OIL FILTER Thwaites Digger Mk 4 Item Part No. Qty. Description Item Part No. Qty. Description T6048 1 Oil Filter 1+ 1 Head Assembly 2 T6171 1 Seal 3+ 1 Spring 4+ 1 Valve Body 5+ 1 Valve 6+ 1 Guide Element (Top) 7+ 1 Centre Tube 8 T6177 1 Element 9+ 1 Sump 10+ 1 Circlip 11+ 1 Guide Element (Bottom) 12+ 1 Seal (Centre Bolt) 13+ 1 Washer 14+ 1 Spring 15+ 1 Seal Sump (Bottom) 16+ 1 Reinforcing Collar 17+ 1 Centre Bolt T6661 1 Hyd. Control Valve 18 T6919 1 Port Plate 19 T6920 2 Valve Body & Spool Boom & Dipper 20 T6921 2 Valve Body & Spool Bucket & Slewing 21 T6922 1 End Plate 22 T6923 10 O Ring 23 T6924 5 O Ring 24 T6925 5 Washer 3/8 25 T6926 5 O Ring + Not available as spare parts 26 T6927 4 Tie Bolt 27 T6742 4 Washer Spring 28 T6928 1 Relief Valve Assembly 29 T6929 1 Back Up Washer 30 T6942 1 O Ring 31 T6935 5 O Ring 32 T6932 2 Relief Valve Assembly 33 T6933 2 Plug 34 T6934 4 Back Up Washer 35 T6935 4 O Ring 36 T6936 4 Deep Washer 37 T6937 4 Washer 38 T6938 4 Spool Spring 39 T6939 4 Shallow Washer 40 T6940 4 Clip Ring 41 T6941 4 O Ring 42 T6942 4 O Ring 43 T6943 4 Lift Check Body 44 T6944 4 Back Up Washer 45 T6945 4 O Ring 46 T6946 4 Lift Check Spring 47 T6947 4 Plunger Lift Check Note: T8221 4 Seal Kit (Comprising items 40, 41, 42, 44 & 45) T8222 4 Seal Kit (Comprising items 42, 35, 41, 34, 45, 44 & 40) T8223 1 Seal Kit (Comprising items 22, 23 & 25) 8

Thwaites Digger Mk 4 HYD. CONTROL VALVE WITH CONTROL FITTINGS NOTE: PIPE (ITEM 27) and ADAPTOR (ITEM 18) ARE FITTED TO PORT AS SHOWN WITH O RING (T7558). ALL OTHER PORTS AS SHOWN REQUIRE SMALLER O RING (T6942) Item Part No. Qty. Description Item Part No. Qty. Description 1 T6661 1 Control Valve 2 T6771 3 Bolt 3 T6775 3 Spring Washer 4 T6862 8 Link Pin 5 T6744 8 Split Pin 6 T6863 8 Link 7 T7637 2 Lever - Outer 8 T7637 2 Lever - Inner 9 T6493 1 Lever Pin 10 T6726 1 Split Pin 11 T6911 1 Rubber Hose 12 T6693 1 Jubilee Clip 13 T6874 1 Banjo 14 T6873 1 Banjo Bolt 15 T6942 8 Hyd. Washer 16 T7397 6 Hyd. Union 17 T6878 2 Hyd. Union 18 T6576 1 Hyd. Union 19 T6248 1 Hyd. Pipe 20 T6880 1 Hyd. Pipe 21 T6325 1 Hyd. Hose 22 T6326 1 Hyd. Hose 23 T6864 1 Hyd. Pipe 24 T6870 1 Hyd. Pipe 25 T6879 1 Hyd. Pipe 26 T6247 1 Hyd. Pipe 27 T6332 1 Hyd. Pipe 28 T7542 4 Lever Knob 29 T5739 2 Washer 9

Thwaites Digger Mk 4 OIL CIRCUIT HYDRAULIC CIRCUIT COMPONENTS: BUCKET RAM DIPPER RAM BOOM RAM SLEWING RAM HYD. CONTROL VALVE HYD. PUMP OIL FILTER SUCTION FILTER T6515 T6515 T6436 T6515 T6661 T8271 T6048 T6047 10

Thwaites Digger Mk 4 OIL PUMP ASSEMBLY (Up to m/c no.4-49887 - Unit no. 5-1621) & OIL PUMP - DRIVE SHAFT ASSEMBLY 11

Thwaites Digger Mk 4 OIL PUMP ASSEMBLY (Up to m/c no.4-49887 - Unit no. 5-1621) & OIL PUMP - DRIVE SHAFT ASSEMBLY Item Part No. Qty. Description 1 T6062 1 Rubber Elbow 2 T6693 2 Jubilee Clip 3 T6343 1 Inlet Elbow 4 T6734 4 Inlet Elbow Cap Screw 5 T6705 4 Inlet Elbow Spring Washer 6 T5591 2 O Ring 7 T6735 4 Bolt 8 T6724 4 Spring Washer 9 T6708 4 Nyloc Nut 10 T6332 1 Hyd. Pipe 11 T6450 1 Hyd. Union 12 T5594 1 Sealing Washer 13 T6457 1 Outlet Elbow 14 T6736 2 Outlet Elbow Cap Screw 15 T6080 1 Body - Hyd. Pump 16 T5612 3 Spring Dowel 17 T5609 2 O Ring 18 T5613 2 O Ring 19 T5603 1 pr C Bushes (matched pair) 20 T6081 1 pr Drive Gear & Driven Gear (matched pair) 21 T5614 1 Assembly Sleeve 22 T5615 1 Key 23 T5604 1 pr A Bushes (matched pair) 24 T5607 1 O Ring 25 T5611 2 Sealing Ring 26 T5610 2 Support Ring 27 T5605 1 Body Cover 28 T5606 8 Cap Screw 29 T5608 1 Shaft Seal 30 T5616 1 Baffle Washer 31 T6737 1 Set Screw 32 T6738 1 Spring Washer 33 T6668 1 Retaining Washer 34 T6215 1 Drive Flange 35 T6739 1 3/8 BSF Grub Screw 1 long 36 T6740 1 Key 37 T6216 1 Hook Flange 38 T6705 4 Spring Washer 39 T6741 4 5/16 BSF Set Screw ¾ long 40 T6672 2 ¼ BSF Long Grease Nipple 41 T6673 1 ¼ BSF Str. Grease Nipple 42 T6467 2 Prop Shaft Unit Pack 43 T5182 1 Prop Shaft Joint Assy - Female End Complete 44 T6675 1 Prop Shaft Joint Assy - Male End Complete 45 T5397 1 Hydraulic Pump Flange 46 T6716 4 Bolt 47 T6717 4 Nyloc Nut OIL PUMP T6046 (used on machines up to no. 4-49887 - Unit 5-1621) NOTE: T6046 is now replaced by T8271, see page 13. 12

Thwaites Digger Mk 4 OIL PUMP ASSEMBLY (From m/c no.4-50014 - Unit no. 6-1622) (Replaced Oil Pump illustrated on Page 11) OIL PUMP - T8271 (From m/c. 4-50014 Unit no. 6-1622) Item Part No. Qty. Description 1 T8271 1 Oil Pump Assembly 2 T8381 1 Seal Kit 3 T6332 1 Hydraulic Pipe - Outlet 4 T8474 2 Cap Screw 5 T6724 8 Spring Washer 6 T8351 1 Elbow - Inlet 7 T5591 1 O Ring 8 T8272 1 Elbow - Outlet 9 T6062 1 Hydraulic Hose - Inlet 10 T5615 1 Key 11 T6708 4 Nut 12 T8354 1 O Ring 13 T6798 4 Bolt 14 T5594 1 Hydraulic Seal 15 T6450 1 Adaptor 16 T8444 2 Cap Screw 17 T6693 1 Jubilee Clip 13