Incorrectly Marked Crankshaft Counterweights on 3500 Engines and on G3500 Engines{1202} Caterpillar

Caterpillar Products:All 3500B and 3500C Engines

Caterpillar Products:Machine Engines All 3500 Series

Engine:Commercial 3500 and 3500B Family All G3500 Family All

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

The counterweights that are on the crankshafts of 3500 Engines and on the crankshafts of G3500 Engines may not be marked in sequential order from the front to the rear of the crankshaft. The crankshaft was balanced with the counterweights in the current positions. Refer to Illustration 1.

Illustration 1	g01346225
Example of incorrect markings on the counterweights

Solution

Ensure that all of the counterweights are marked in sequential order.

• 3508 Engines start with the number 1 and end with the number 6

• 3512 Engines start with the number 1 and end with the number 12

• 3516 Engines start with the number 1 and end with the number 16

• 3520 Engines start with the number 1 and end with the number 20

The number 1 counterweight must be installed at the front of the crankshaft. The last counterweight must be installed at the rear of the crankshaft.

The front of the crankshaft does not have notches. The rear of the crankshaft has two notches. Refer to Illustration 2 and Illustration 3.

Illustration 2	g01346226
Front view (1) Front of the crankshaft

Illustration 3	g01346227
Rear view (2) Rear of the crankshaft (3) Notches in rear face of the crankshaft

If the counterweights are not marked in sequential order from the front to the rear of the crankshaft, stamp an "X" through the numbers. Stamp the correct numbers in numerical order before removing the counterweights. Start at the front of the crankshaft.