Engine Overheats (Replace Engine Fan Clutch Assembly)
| Subject: | Engine Overheats (Replace Engine Fan Clutch Assembly) |
| Models: | 1997-98 Chevrolet and GMC T6/7 Series (VIN Code C) Medium Duty Tilt Cab Trucks -- with 3116 Caterpillar® Diesel Engines |
| Equipped with 26 Inch Fan Blades (RPOs LZY, LQZ, LVZ, LRU, VO1, MWE, MWF, LVX, LVT, LVY) |
This bulletin is being revised to add the 1998 model year, change the Labor Operation number, and to update information in the Models and Correction sections. Please discard Corporate Bulletin Number 86-62-08 (Section 6 -- Engine).
Condition
Some owners may comment that the engine overheat lamp comes on and that the temperature gauge is in the red zone. The audible overheat alarm may also sound.
Cause
Calibration of the fan clutch may be incorrect. This may cause the fan clutch to engage too late. This will cause the audible alarm to sound.
The disengaged speed of the clutch may be too slow. This may cause the fan clutch sensor to become unresponsive due to a lack of airflow.
Correction
A new fan clutch has been released with the following features:
| • | The calibration is revised. |
| • | The disengage speed is higher. This ensures the proper cycling of the cooling fan. |
| • | The engagement has been revised to on/off instead of modulating. |
Replace the engine fan clutch assembly using the part number listed below. Use the Service Procedure in the Caterpillar® Service Manual.
Parts Information
P/N | Description | Quantity |
|---|---|---|
15008794 | Clutch Assembly, Engine Fan | 1 |
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the following information:
Labor Operation | Description | Labor Time |
|---|---|---|
J9220 | Clutch Assembly, Fan - R&R or Replace | Use Published Labor Operation Time |
