Product Support Program For Installing A New Evaporator Core And Rerouting The Air Flow To Improve The Cooling Inside The Cab Of Certain 65C, 70C, 75C And 85C Challenger Tractors Caterpillar

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 can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS0938" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.

Termination Date

Problem

A new evaporator core needs to be installed and air flow rerouted to improve the cooling inside the cabs of certain CH65C, CH70C, CH75C and CH85C Challenger Tractors.

Affected Product
Model & Identification Number

Group 1

CH65C (2ZJ1707-1964)

CH70C (2YL1289-1319)

CH75C (4KK1958-2229)

CH85C (9TK1473-1764)

Group 2

CH65C (2ZJ1-1706)

CH70C (2YL1-1288)

CH75C (4KK1-1957)

CH85C (9TK1-1472)

Parts Needed

Group 1

1 - 9U2759 Hose (80 cm)

2 - 9U2760 Louver Assembly

1 - 1244636 Duct Assembly

1 - 1244642 Duct Assembly

1 - 1255841 Coil Assembly

Group 2

1 - 9U2759 Hose (80 cm)

2 - 9U2760 Louver Assembly

2 - 1162643 Insulation

1 - 1162644 Insulation

1 - 1244636 Duct Assembly

1 - 1244642 Duct Assembly

1 - 1255841 Coil Assembly

Action Required

Group 1

1. Install a new 1255841 Coil Assembly in the air conditioner.

2. Redirect the lower vent air flow through the larger upper cab vents. See Illustration 1.

NOTE: If desired (and at the customer's expense), the 9U2401 Panel (Item 7) may be replaced with a 1244807 Panel to eliminate the lower two louver locations that are no longer used.

Group 2

Perform the rework described in Group 1 above. Additionally, on some earlier C Series models, three foam blocks (Illustration 1, Items 5 and 6) can be added to the chamber beneath the 2 duct assemblies as shown in Illustration 1, View A-A. These foam blocks eliminate turbulence in the air chamber and increase air flow approximately 10% while also reducing noise substantially from the ventilation system. After the duct assemblies (Illustration 1, Item 1 and 2) are removed, it is easy to see whether or not the insulation is in place. If it is not, add the insulation, ensuring that the foam blocks are oriented as shown in Illustration 1 and no air passages are blocked by foam material.

Service Claim Allowances

NOTE: This is a 3-hour job regardless of whether it is a Group 1 or a Group 2 machine.

Parts Disposition

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

Illustration 1