SERVICE METER ASSEM. 9S5123 - Caterpillar

On-highway Engine:
C15 (S/N: MXS1-UP)
Truck Engine News SEBD6776, March 2005, "Adjustment of the Air Gap for the Secondary Speed/Timing Sensor". Disregard this article. See the article that follows.A 126-8481 Washer has been released for adjusting the air gap for the secondary speed/timing sensor on the engines that are listed above. The 126-8481 Washer should be installed if the engine experiences any of the following conditions:
The engine is stalling shortly after starting.
Engine Control Module (ECM) records a 64-08 fault code.These conditions can be caused by a lost timing signal at the camshaft. If the engine experiences either of these conditions, perform the following procedure.
Illustration 1 g01221421
(A) Distance between the seat of the sensor and the sensor tip. (B) Distance between the seat of the sensor and the gear tooth
Do not remove the cover for the camshaft and idler gears in order to check the air gap.
Remove the secondary speed/timing sensor from the front housing.
Measure the distance from the seat of the sensor to the tip of the sensor. Refer to illustration 1.
Measure the distance from the seat of the sensor to the gear tooth by using a depth micrometer. Refer to illustration 1.
Subtract the difference between Step 3 and Step 4. This number is the air gap.
Verify that the air gap is 1.00 0.50 mm (0.039 0.020 inch).
If the air gap is not 1.00 0.50 mm (0.039 0.020 inch), do not replace the secondary speed/timing sensor. Install the 126-8481 Washer in order to provide the proper air gap. When the washer is installed on the sensor do not exceed 1.00 0.50 mm (0.039 0.020 inch) air gap.Dimensions for 126-8481 Washer Outside Diameter ... 28.10 0.13 mm (1.106 0.005 inch) Inside Diameter ... 21.10 0.13 mm (0.831 0.005 inch) Thickness ... 0.51 0.03 mm