Loss of Coolant Flow Events on 793D Mining Trucks{1395, 1438, 7601} Caterpillar

Off-Highway Truck/Tractor:

793D (S/N: FDB1-771)

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

793D Mining Trucks may experience the events of loss of coolant flow. VIMS will generate a "ENG COOL FLOW TOO LOW" message to the message center. This message will be logged in the chronological log for events.

Loss of coolant flow is attributable to fatigue and breakage of the wiring leads on the 171-8708 Flow Switch for machines with at least three hundred hours of machine operation. For the above listed machines, the 4P-7581 Clip is used to secure the wiring for the flow switch and the electrical connection.

Other causes of "ENG COOL FLOW TOO LOW" events exist. Caterpillar continues the investigation in order to determine a corrective action.

Solution

Illustration 1	g01686053
(1) 130-5300 Clip (2) Loop (3) Tie-wrap

Replace the 4P-7581 Clip with the 130-5300 Clip (1). Secure the wiring lead for the flow switch to the body of the switch at the midpoint of the wiring with a tie-wrap (3). Provide a cable loop (2) on the end of the switch and on the end of the connectors of the lead in order to relieve stress. Refer to Illustration 1.