The Air Conditioning System Needs To Be Reworked To Prevent Excessive Condensation From Collecting In The Drain Pan On Certain 416C, 426C, 436C, 428C And 438C Backhoe Loaders Caterpillar

The Air Conditioning System Needs To Be Reworked To Prevent Excessive Condensation From Collecting In The Drain Pan On Certain 416C, 426C, 436C, 428C And 438C Backhoe Loaders

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Caterpillar: Confidential Yellow

NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

NOTE: This Program must be administered as soon as possible. When reporting the repair, use "PI3048" as the Part Number, "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description Code. Exception: If the repair is done after failure, use "PI3048" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.

NOTE: This Revised Service Letter replaces the August 6, 1997 (Revised September 1997) Service Letter. Changes have been made to an O-Ring Seal part number in the Rework Procedure.

Completion Date

February 28, 1998

Termination Date

August 31, 1998

Problem

The air conditioning system needs to be reworked to prevent excessive condensation from collecting in the drain pan on certain 416C, 426C, 436C, 428C and 438C Backhoe Loaders. Air conditioning units on some initial C-series Backhoe Loaders have experienced problems with condensation collection which, under the right conditions, can spill over into the headliner and into the cab. New units are available which will prevent this problem from occurring.

Affected Product
Model & Identification Number

416C (1XR316, 1XR339, 1XR344, 1XR345, 1XR353, 1XR363, 1XR365, 1XR370, 1XR385, 1XR390, 1XR399, 1XR410, 1XR411, 1XR423, 1XR425, 5YN240 , 5YN243, 5YN247, 5YN252, 5YN253, 5YN266, 5YN271, 5YN290, 5YN299, 5YN347, 5YN348, 5YN363, 5YN366, 5YN375, 5YN384, 5YN386, 5YN390, 5YN404, 5YN405, 5YN408, 5YN409, 5YN425, 5YN433-435, 5YN441, 5YN455, 5YN456, 5YN459, 5YN471, 5YN472, 5YN474, 5YN489, 5YN490, 5YN493, 5YN508-510, 5YN525, 5YN526, 5YN545, 5YN546, 5YN578, 5YN580, 5YN584, 5YN606, 5YN611, 5YN612, 5YN629, 5YN630, 5YN643, 5YN644, 5YN673, 5YN674, 5YN678-680, 5YN695, 5YN696, 5YN709, 5YN718-721, 5YN796, 5YN797, 5YN828, 5YN829, 5YN845, 5YN849, 5YN883, 5YN1000, 5YN1073, 5YN1437, 5YN1441, 5YN1442, 5YN1476, 1WR318 , 1WR332, 1WR333, 1WR347, 1WR358, 1WR363, 1WR438, 4ZN217 , 4ZN366, 4ZN384, 4ZN386, 4ZN387, 4ZN394, 4ZN403, 4ZN419, 4ZN421, 4ZN424, 4ZN426, 4ZN429, 4ZN439, 4ZN449, 4ZN456, 4ZN465, 4ZN469, 4ZN474, 4ZN489, 4ZN492, 4ZN501, 4ZN504, 4ZN508, 4ZN536, 4ZN540, 4ZN546, 4ZN549-552, 4ZN558, 4ZN561, 4ZN575-577, 4ZN580, 4ZN584, 4ZN586, 4ZN591, 4ZN600, 4ZN609, 4ZN657, 4ZN660, 4ZN688, 4ZN696, 4ZN699, 4ZN702, 4ZN724, 4ZN747, 4ZN754, 4ZN755, 4ZN762, 4ZN1164, 4ZN1171, 4ZN1186, 4ZN1188, 4ZN1203 )

426C (1YR233, 6XN240 , 6XN241, 6XN248, 6XN265, 6XN274, 6XN280, 6XN284, 6XN297, 6XN299, 6XN313-315, 6XN317, 6XN325, 6XN364, 6XN422, 6XN424, 6XN425, 6XN438 )

436C (1PR298, 1PR301, 8TN184 , 8TN187, 8TN188, 8TN198, 8TN202, 8TN217, 8TN218, 8TN227, 8TN233)

428C (2CR354, 2CR355, 2CR357, 2CR358, 2CR359, 2CR449, 2CR482, 2CR623, 2CR650, 2CR656, 2CR910, 2CR1082, 2CR1083, 2CR1084, 2CR1096, 2CR1097, 2CR1098, 2CR1103-1105, 2CR1114, 2CR1116, 2CR1123, 2CR1131, 2CR1132, 2CR1144, 2CR1155, 2CR1173, 2CR1176, 2CR1177, 2CR1181, 2CR1182, 2CR1187, 2CR1188, 2CR1193, 2CR1194, 2CR1198, 2CR1199, 2CR1207, 2CR1251, 2CR1252, 2CR1253, 2CR1255-1262, 2CR1274, 2CR1398, 2CR1402, 2CR1403, 2CR1405-1407, 2CR1410-1412, 2CR1416, 2CR1418, 2CR1424, 2CR1425, 2CR1429, 2CR1504, 2CR1540, 2CR1633, 2CR1695, 8RN309 , 8RN311-314, 8RN316, 8RN317, 8RN321, 8RN322, 8RN326, 8RN327, 8RN331, 8RN332, 8RN337, 8RN460, 8RN469, 8RN472, 8RN473, 8RN502, 8RN505, 8RN506, 8RN509, 8RN510, 8RN512, 8RN513, 8RN515, 8RN549, 8RN552, 8RN553, 8RN561-564, 8RN566, 8RN567, 8RN608, 8RN609, 8RN615, 8RN616 )

438C (1TR446, 1TR448, 1TR450, 1TR476, 1TR502, 1TR563, 1TR571, 1TR578, 1TR592, 1TR598, 1JR404 , 1JR406,2DR393, 2DR471, 2DR498, 2DR518, 2DR628, 2DR631, 9KN352 )

Parts Needed

1 - 1489152 Kit

Action Required

See the attached procedure.

Owner Notification

U.S. and Canadian owners will receive the attached Owner Notification.

Service Claim Allowances

NOTE: This is a 7-hour job.

NOTE: U.S. and Canadian Dealers Only - Eligible dealers may enter a Type 2 SIMS Report.

Parts Disposition

Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.

NOTE: MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.

Attach.

(1-Owner Notification)

(2-Rework Procedure)

Copy Of Owner Notification For U.S. And Canadian Owners

Rework Procedure

Before beginning, identify each part inside the 1489152 Kit.Each kit contains:

2 1485651 Bracket

2 1487508 Plate

1 1456626 Sleeve

60 5P4829 Tube (dm)

2 7T9793 Valve

1 1429660 Conditioner Group

1 1489259 Insulation

1 1489260 Insulation

1 1489261 Insulation

1 1489262 Insulation

4 3S2093 Strap

2 1449973 Clamp

8 1010003 Fastener

2 9R4917 Rod Control

2 8T4133 Nut

10 5P4610 Insulation Strip (dm)

The following parts and tools will be needed for the rework:

9X7383 O-ring Hand held grinder

9X7382 O-ring Drill, metric drill bits

4C9612 RTV sealant Caulk gun

These steps should be performed in order as much as possible:

I. REMOVING HEADLINER

1. Reclaim air conditioner charge (approximately 4.0 lbs/R134a) from machine. Use the recommended EPA reclaim equipment.

2. See Illustration 1. Remove both 1219813 and 1219814 Rear Ducts. Remove 2 - 8Y7446 Screws per louver and remove 4 - 8Y6388 Louvers. Loosen 2 - 8T4189 Bolts per duct and slide the rear ducts toward the rear window. The 1318158 Plate will fall into the duct and the ducts can be slipped over the bolts and washers which can remain in place. The ducts should be placed outside the cab to prevent damage.

3. The radio adapter, switch plate dome lamp are located in the front headliner. Remove the radio (if equipped), connector and antenna. Remove 1219751 Adapter by removing 2 - 9X2045 Bolts. Remove fuse cover, then remove 1055157 Switch Plate by removing 3 - 9X1046 Screws. Remove the dome lamp from the headliner and disconnect two connectors. Identify all harness connectors for subsequent reassembly. Disconnect the switches from the harness.

4. Open fresh 1049484 Air Filter Access Door by unscrewing 2 - 7K3262 quarter turn screws near the windshield. Remove door by lifting hinge tabs from slots. Place door outside the cab.

5. See Illustration 2. Remove fresh air filter inside air conditioner unit by unlocking the clips on both ends of the filter. Place filter outside the cab.

6. See Illustration 3. The front headliner is now supported at the edges by the cab cladding. Remove the right side B-post cover. Remove the headliner by first sliding the left-hand side off of the cab cladding, then slide the right-hand side. Lower the rear of the headliner toward the seat, then slide the front off of the cab cladding. Remove the headliner from the cab.

II. MODIFY FRONT HEADLINER

7. The two square blower inlet holes in the black headliner ducts must be enlarged. Lay the headliner on a flat work area so that the black ducts on the top side of the headliner are up. Protect the bottom headliner surface from damage. Use a 1487508 Plate as a template for enlarging the large hole and locating the four smaller holes. See Illustration 4. With the rounded corners up, align the large hole in the 1487508 Plate with the sides and bottom of a blower inlet hole. Use a suitable marker to scribe the top area of the blower inlet hole that needs to be removed. Transfer the centers of the small holes to the duct. Repeat for the second blower inlet hole. Use a suitable tool to remove material from both blower inlet holes. Drill (8) 4.7 mm diameter holes.

8. Align (1) 1487508 Plate to each blower inlet hole. The rounded corners of each plate should extend above the top radius of the ducts. Assemble the plates to the ducts using 8 - 1010003 Fasteners.

9. See Illustration 5. Insulate all outside surfaces of the black ducts on front headliner with self-adhesive insulation strips. The insulation should be applied such that no outer surfaces of the duct remain exposed. See Illustration 6. Any exposed surfaces or gaps between insulation could cause condensation to collect. Use 1489259 and 1489260 Insulation for the right duct and 1489261 and 1489262 Insulation for the left duct.

NOTE: Test location for insulation strips before exposing adhesive. Peel adhesive backing off in small sections to ease installation.

10. See Illustration 7. Run a bead of 4C9612 RTV around all four sides of each 1487508 Plate to provide an air tight seal between the 2 plates and the ducts.

III. DISCONNECTING HOSES, HARNESSES, SWITCHES, ETC.

11. Remove 5P4610 Insulation Tape to gain access to the air conditioner line fittings on RHS of air conditioner unit. If necessary, bend speaker bracket to gain access to fittings. Speaker bracket will not be reused. Disconnect lower air conditioner line from the air conditioner unit (evaporator). Disconnect 2 clear drain tubes from drain ports.

12. Identify all connectors and harness routing before disconnecting harness and switches. Disconnect the harness connections to both radio speakers, to front wiper, to dome light and to radio. Disconnect air conditioner ground from the ground boss on the roof. Disconnect all air conditioner harness connections from the cab. Remove tie-wraps that hold air conditioner hoses to B-post.

13. Remove (2) 2V0099 Knobs from thermostat and fan switches. Remove 2 retaining nuts and remove switches from 1230253 Bracket.

14. See Illustration 8. Six 8T4137 Bolts secure the 1020515 Air Conditioner Unit to the roof. Remove 1 - 8T4137 Bolt from each side of the air conditioner unit and replace 2 bolts with 2 - 9R4917 Studs and 2 - 8T4133 Nuts. These studs and nuts will support the unit as the remaining four bolts are removed. Remove the remaining 4 - 8T4137 Bolts. Gradually lower the unit on the studs until the unit rests on the nuts.

NOTE: Two people are recommended for Steps 15 and 19.Air conditioner unit weighs approximately 60 lb.

15. Disconnect upper air conditioner line from the air conditioner unit (evaporator). Lift the air conditioner unit off of the nuts. Remove the nuts and lower the unit. Remove the air conditioner unit from the cab.

16. Remove both 1246096 Speakers from 1321363 Brackets by removing 4 - 6V2410 Screws and 8T4205 Washers per speaker. Attach speakers to 1485651 Brackets using 4 - 6V2410 Screws and 8T4205 Washers. The speakers will attach to the headliner and not the new air conditioner unit. Store the speaker assemblies for later installation.

IV. INSTALLING NEW AIR CONDITIONER UNIT

17. Prepare the new 1429660 Air Conditioner Unit for installation by removing the protective shipping materials from controls. Cut tie-straps that hold the capillary tube and harness to the unit.

18. Discard the old sheet-metal unit.

19. Place new 1429660 Air Conditioner Unit into cab. Raise unit onto (2) 9R4917 Studs and install (2) 8T4133 Nuts to support unit until (4) 8T4137 Bolts can be installed.

20. New air conditioning unit requires larger hose on top. Hose routing from B-column needs to be adjusted to allow larger hose to reach top. Install 1456626 Insulation Sleeve over suction hose (larger diameter). Add 9X7383 O-ring and connect larger hose fitting. Tighten fitting to 40 N·m. Slide insulation over hose coupling and secure with two 3S2093 Tie - Straps. Wrap ends of insulation with 2 strips of 5P4610 Insulation Tape.

21. Raise the unit to the roof and start (4) 8T4137 Bolts. Remove 2 studs and start remaining (2) 8T4137 Bolts. Tighten the 6 bolts to 55 N·m.

22. Add 9X7382 O-ring and connect high-pressure hose (smaller diameter). Tighten fitting to a torque of 27 N·m. Wrap exposed fitting with 1 strip of 5P4610 Insulation Tape.

23. Connect air conditioner grounds and cab grounds onto the ground boss on the roof.

24. Connect air conditioner harness to cab harness and secure harnesses and radio coax with 3S2093 Tie - Wraps.

25. Install thermostat and fan switch into the bracket. Install retaining nuts and (2) 2V0099 Knobs.

26. Run pressure tests to check for leaks.

V. INSTALLING LONGER DRAIN TUBES AND/OR CHECK VALVES

27. The clear air conditioner drain tubes run from the air conditioner unit to a hole near the top of the A-posts. If the tube extends through the A-post and exits through a hole in the bottom of the A-post, verify the orientation of the 7T9793 Check Valve, then proceed to Step 31. Check valve should be oriented so that the pointed end is facing the ground.

28. If the drain tube does not exit through the bottom hole, install new longer drain lines. Remove short drain lines from top hole in A-posts and discard. Cut (2) 30 dm long tubes from 5P4820 Bulk Tubing. Cut one end of each tube at a 45 degree angle. Insert the angled end of the tube into the bottom hole of the A-post above the fuel tank. Push and turn the tube into the post until the end is visible through the top hole of the A-post (Note: a soapy water solution may be used to pass the tube through the A-post). Use a pair of needle-nose pliers to grab and pull the tube through the top hole in the A-post. Cut the angle from the end of the tube leaving a square, undamaged end.

29. Pull enough tube from the post to attach the tube to a drain port on the air conditioner unit. Install 1 - 1449973 Clamp loosely onto the tube and gently push the tube onto the drain port. Tighten clamp. Route the bottom end of the drain tube along the hydraulic lines below the cab towards the rear mounting bolts of the fuel tank. See Illustration 9. The tube should run vertically, between the tank and frame, just in front of the rear mounting bolts. The tube should extend to the bottom of the frame rail. Secure the tube to a hydraulic line below the cab with (1) 3S2093 Tie-Strap. The tube should not sag at any point or drain water will be trapped. Repeat process for other side.

30. 7T9793 Check Valve must be installed in the bottom end of each drain tube. Lubricate the large diameters of the valve with a liberal amount of O-ring lube. Insert the round end of the valve squarely into the tube as far as possible by hand. Use a suitable tool to gently push the top of the valve 75 mm into the tube. Repeat process for other tube.

VI. INSTALLING HEADLINER AND SPEAKERS

31. Install front headliner by reversing disassembly process. Be sure that 1487508 Plates, attached to the headliner ducts in step 8, do not cut or damage the foam gaskets on the air conditioner blower outlets. 1487508 Plates must seat/seal on the air conditioner blower outlet gaskets to prevent cooled air from leaking into the headliner space. The gaskets should not be pushed into the air conditioner blower outlets where they can restrict airflow.

32. Remove both 1013055 Speaker Covers from headliner by removing 4 - 1130920 Screws per cover. Store in cab for next step. Pull the speaker wires (508 - pu and 509 - wh) through the speaker holes in the front headliner. Attach the wire terminals to the speakers terminals. The speaker bracket assembly was assembled in step 15. Attach speaker bracket assembly and speaker cover to headliner using 4 -1130920 Screws per cover. The speaker cover will sandwich the speaker to the headliner. See Illustration 10.

33. Install 1219751 Radio Adapter with the correct screws. Connect harness to switches and radio (if equipped). The switch plate should be supported from the front while reconnecting the harness so the harness does not push the switch out of it's slot and damage the switch. Install 1055157 Switch Bracket with the correct screws.

34. Perform electrical check.

35. Install both rear air conditioner ducts and 4 louvers.

36. Clean and install fresh air filter.

37. Install fresh air filter access door. Make sure both quarter turn screws are tight.

VII. AIR CONDITIONER SYSTEM CHECKS

38. Recharge system with 4.0 lbs of R134A.

39. Test air conditioner system function.

Illustration 1