- Backhoe Loader
- 427F2 (S/N: HWK1-UP)
- 428F2 (S/N: LYG1-UP; HWN1-UP)
- 434F2 (S/N: LYK1-UP; HWR1-UP)
- 428F2 (S/N: LYG1-UP; HWN1-UP)
Introduction
Do not perform any procedure in this Special Instruction until you have read the information and you understand the information.
- This kit will only work on machines fitted with MP auxiliary lines.
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Table 1 428F2 434F2 QC Compatible 450-8537 Bank Valve Ar 450-8560 Bank Valve Ar YES 450-8539 Bank Valve Ar 450-8562 Bank Valve Ar YES 450-8541 Bank Valve Ar - YES 450-8542 Bank Valve Ar - YES 450-8536 Bank Valve Ar 450-8562 Bank Valve Ar NO(1) 450-8540 Bank Valve Ar - NO(1) Show/hide table(1) The extra lines and control lever can be retro-fitted, but will obviously increase the cost, and there are no instructions available to retrofit these parts. - The continuous flow option is not available on the 427, 428, or 434 models.
For work tools that require continuous flow, the operator will be required to hold the operation lever in position all the time that flow is required.
Safety Section
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Do not operate or work on this machine unless you have read and understand the instructions and warnings in the Operation and Maintenance Manuals. Failure to follow the instructions or heed the warnings could result in injury or death. Contact your Cat dealer for replacement manuals. Proper care is your responsibility. |
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Personal injury or death can result from sudden work tool movement. Sudden movement of the work tool can cause injury to persons near the work tool. To prevent injury or death, make sure that the area around the work tool is clear of personnel and obstructions before operating the work tool. |
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Illustration 1 | g00104545 |
Prevent the machine from movement. Park the machine on a level surface.
Attach a "Do Not Operate" warning tag or a similar warning tag to the start switch or to the controls before you service or repair the equipment . These warning tags (Special Instruction, SEHS7332) are available from your Cat dealer.
Required Parts
Required Parts | |||
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Item | Qty | Part Number | Description |
1 | 1 | Quick Coupler Ar | |
1 | Quick Coupler Ar | ||
2 | 1 | Film | |
3 | 1 | Film | |
4(3) | 1 | Terminal | |
1 | Ring Terminal | ||
1 | Connecting Plug Kit | ||
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- | 16awg or 1mm2 wire (red) | |
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- | 16awg or 1mm2 wire (black) | |
2 | Connector Socket | ||
10 | Seal Plug | ||
5 | 1 | - | OMM update sheet |
(1) | For 427F2 and 428F2 machines. |
(2) | For 434F2 machines. |
(3) | Dealer fabricated harness. |
Installing the Front Coupler Kit
- Park the machine on level ground and lower the implements to the ground.
- Remove the front loader bucket from the machine.
- Cap the hoses that were attached to the bucket to reduce oil spillage and contamination.
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Illustration 2 g06033760 Quick coupler arrangement (1)
( 1a)387-6662 Work Tool Wiring Group
(1b)456-0567 Coupler Lines Group
(1c) Quick coupler - Install quick coupler (1c) using the pins and shims that were removed when removing the loader bucket.
Note: The coupler pins should be shimmed to achieve a maximum lateral clearance of
1 mm (0.040 inch) . Refer to Specifications , UENR3746 , Lift Arm. - Reconnect the auxiliary hoses that were originally connected to the bucket, to the coupler connectors.
- Route wiring harness (1a) to follow the auxiliary hose on the right-hand side of the machine as shown in Illustration 2.
- Secure harness (1a) at regular points using cable ties. The end of the harness should be terminated at the bottom of the cab "A" pillar.
Installing the Front Console Harness
- Inside the cab, remove the floor mat, and the lower section of the front console.
- Remove the three switch blanks in the lower left-hand side of the front console.
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Illustration 3 g06034109 View of front console area
(1a)387-6664 Quick Coupler Harness Assembly - Install harness (1a) in the front console and secure with cable ties.
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Illustration 4 g06034180 View of area under the cab near the "A" pillar
(1a)387-6664 Quick Coupler Harness Assembly - Under the cab, connect the existing harness to harness (1a) that has been routed down the loader arm at the bottom of the right-hand "A" pillar of the cab. Secure in place with cable ties.
- The other end of harness (1a) (12-pin connector) will connect be to the power supply from the spare fuse "41" in the following steps.
Switch Installation
The quick coupler switches are on the left-hand side of the front console. There are four blank switch covers installed in a row.
- Remove the blank switch covers for switch (1d), (1f), and (1g). Do not remove switch cover for switch (1e) as it will not be used.
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Table 3 Switch Pin Identification Switch Pin 1 Pin 2 Pin 3 (1d) Quick Coupler 779–WH 143–BR (1e) Continuous Flow not used not used not used (1f) External Power 143–BR 578–BU (1g) Broom Angle L998–OR 143–BR - Using wire identification Table 3, plug the correct connector into each switch.
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Illustration 5 | g06034211 |
(1d) Switch - quick coupler
(1e) Switch - continuous flow (1f) Switch - external power (1g) Switch - broom angle |
Fabrication of Harness
A dealer fabricated harness is required to connect the coupler harness to fuse "F41" on the fuse board.
- Fabricate harness (4) as shown in Illustration 6.
Connect red wire (4c) of
1400 mm (55.12 inch) in length from terminal (4a) to terminal "1" of connector (4e).Connect black wire (4d) of
1000 mm (39.37 inch) in length from ring terminal (4b) to terminal "3" of connector (4e).Note: Connector (4e) consist of the following, one 155-2255 Connecting Plug Kit, two 8T-8730 Connector Pins, and ten 8T-8737 Seal Plugs.
Reference: Refer to Special Instruction , M0065402 , "Procedure For Connecting To The Spare Fuses on F2 Series Backhoe Loaders".
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Illustration 6 | g06034887 |
Dealer fabricated harness (4) ( 4a) (4b) (4c) Red wire (4d) Black wire (4e) Connector |
Installation of Fabricated Harness
- Working under the machine, connect the plug from 155-2255 Connecting Plug Kit of the dealer fabricated harness to the 12-pin connector on the recently installed front console harness. This connection should be located under the right-hand side of the cab under the right-hand door.
- Push the red wire of the dealer fabricated harness up through the rubber gasket in the cab floor where the main harness goes through. Refer to Illustration 7.
Note: Ensure that there is no excessive wire hanging under the machine.
- Inside the machine, remove the fuse panel by removing the six screws and carefully pulling the panel forward. The red wire should be visible coming through the floor gasket.
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Illustration 9 g06008734 View of fuse panel - location of connector "X10"
(C) Front view of fuse board showing spare fuse locations
(D) Rear view of fuse board showing connector locationsShow/hide tableIllustration 10 g06034926 View of connector "X10" - location of Pin 9
(E) Pin 9 - The red wire should be connected into "X10", pin 9 in the harness plugged into the rear of the fuse panel. Refer to Special Instruction , M0065402 , "Procedure For Connecting To The Spare Fuses on F2 Series Backhoe Loaders"for how to connect to Pin 9.
- Using cable ties, tie the red cable along the main harness.
- Reinstall the fuse board and refit the six screws securing the panel.
- Inside the lid of the fuse cover, make a note that fuse "41" is used for the front coupler.
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Illustration 11 g06034942 Black wire of dealer fabricated harness (4) Show/hide tableIllustration 12 g06009290 Ground stud location Show/hide tableIllustration 13 g06009299 View of area G
(H) Incorrect stud to install new ring terminal
(J) Correct stud to install new ring terminal - Back under the machine, the black wire on the dealer fabricated harness should then be connected to the cab ground point "J" as shown in Illustration 13. Special Instruction , M0065402 , "Procedure For Connecting To The Spare Fuses on F2 Series Backhoe Loaders" for how to connect to the cab ground point under the cab.
Note: Ensure that all cables are secured with cable ties to prevent any damage.
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Illustration 7 | g06034914 |
Red wire of dealer fabricated harness (4) |
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Illustration 8 | g06034916 |
Red wire of dealer fabricated harness (4) |
Decal Installation
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Illustration 14 | g06034944 |
(2) |
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Illustration 15 | g06034947 |
(3) |
- Place film (2) on the right-hand side of the front lower console.
- Place film (3) under the loader lever, as a replacement for the original decal.
OMM Supplement
The following section ("Operator Controls") is a replacement for the current information within the Operation and Maintenance Manual (OMM). This information should be printed and kept with the OMM in the machine for operator reference.
Quick Coupler Control Switch (If Equipped)
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Improper attachment of work tools could result in injury or death. Do not operate this machine until you have positive indication that the coupler pins are fully engaged. Check for engagement by: 1. Tilt the work tool down. 2. Put downward pressure on the work tool. 3. Back the machine up and make sure there is not any movement between the work tool and the quick coupler assembly. |
The quick coupler pin switch with the red lock button is used to engage the pins. The quick coupler pin switch is also used to disengage the quick coupler pins.
NOTICE |
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Auxiliary hoses for work tools must be removed before the quick coupler pins are disengaged. Pulling the work tools with the auxiliary hoses could result in machine damage. |
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Illustration 16 | g06035316 |
(1) Quick coupler control switch (if equipped)
(2) Loader auxiliary lever |
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Disengage - Pull the red button downward and push downward on the top of the quick coupler control switch (1). Hold the switch in position and at the same time, operate the loader auxiliary lever (2) FORward. This operation will UNLOCK the coupler pins. |
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Engage - Push downward on the bottom of the quick coupler control switch (1). Hold the switch in position and at the same time, operate the loader auxiliary lever (2) backward. This operation will LOCK the coupler pins. |
NOTICE |
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Auxiliary hoses for work tools must be attached after the quick coupler pins are engaged. Operating the work tool without the hoses properly attached may result in damage to the work tool. |
Note: Operating the quick coupler switch will deactivate the ride control system for a short time. Deactivating the ride control systems enables easier changing of work tools.
Verify Operation
- Check coupler operation by following the instructions listed in the OMM Supplement section. Refer to "Operator Controls".
- Ensure that there are no leaks on the coupler hoses.