The Blower Fan Group Bearing May Fail on 793F AC, 795F AC, and 794 AC Off-Highway Trucks {5058} Caterpillar

Off Highway Truck

793F AC (S/N: EMD1-UP)

794 AC AC (S/N: MN51-UP)

795F (S/N: SNT1-UP)

795F AC (S/N: ERM1-UP)

Introduction

The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

Illustration 1	g03683357
View of the bearing block group

The bearing block may fail prematurely. Indicators of bearing failure are high bearing surface temperatures or grease leakage from the lower sealing surface.

Solution

The issue can be contained with proper inspection and monitoring for grease leaking and high bearing temperatures as part of the machine walk around inspection. The walk around inspections should be performed prior to start up and prior to the 250 Service Hour or Monthly inspection.

A temperature indicator sticker can be installed to monitor the temperature of the bearings. Refer to the following steps in order to install the temperature indicator sticker.

Required Parts

Show/hide table

Illustration 2	g03683498
View of the bearing and blower motor

1. Install temperature indicator (1) on the lower portion of the bearing block in the location that is shown in Illustration 2.

2. If the temperature indicator indicates that the bearing is greater than 93° C (199° F) or if grease leakage is identified, then replace bearing block. Replace the bearing block with the same part number and install new temperature indicator (1).

3. The new bearing block must be inspected prior to installation. Inspect the axial run-out of the bearing. The axial run-out of the bearing must be between 0.05 mm (0.002 inch) and 0 mm (0.00 inch).

   Note: If the bearing is outside of the specifications, reject the part to Caterpillar parts system.

Contact Product Support if a replacement of the bearing block is made.