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Makes 🢒 GMC_Truck 🢒 1997 🢒 GMC MD Bus Chassis (B Model) 🢒 Bulletins 🢒 Premature Fan Clutch Engagement (Replace Radiator Shutter Engine Coolant Sensor)

Premature Fan Clutch Engagement (Replace Radiator Shutter Engine Coolant Sensor)

Subject:Premature Fan Clutch Engagement (Replace Radiator Shutter Engine Coolant Sensor)

Models:1996-2000 Chevrolet and GMC B6-7 Medium Duty School Bus Models
with 3116/3126 Caterpillar® Diesel Engines and Radiator Shutters (RPO V04)


Condition

Some drivers may comment on the fan clutch engaging before the radiator shutters have opened. This can be noticed by a loud fan noise heard under the hood.

Cause

Improper engagement timing between the shutters and the fan clutch may cause this condition.

Correction

Replace the radiator shutter engine coolant sensor with P/N 15674810. The new sensor has an 85°C (185°F) top tank temperature operating setting. This will lower the shutter operation engagement timing and should allow the shutters to open sooner. Use the following procedure and the part number listed below.


    Object Number: 203590 Size: SH
  1. Partially drain the coolant into a suitable container for reuse.
  2. Disconnect the electrical connector.
  3. Remove the radiator shutter engine coolant sensor (1).
  4. Install the radiator shutter engine coolant sensor (1).

    5. Tighten
    Tighten the sensor to 35 N·m (26 lb ft).

  5. Connect the electrical connector.
  6. Refill the cooling system as necessary.

Parts Information

Part Number

Description

Qty

15674810

Sensor Asm., Rad Shutter Engine Coolant

1

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

J9480

Sensor Asm., Radiator Shutter Engine Coolant - Replace

0.4 hr*

* This is a new labor operation number for use on this application. The next update of the Labor Time Guide will contain this change.