2001/12/01 Caterpillar

Engines:

3606 (S/N: 8RB793-UP)

3608 (S/N: 6MC636-UP; 1ZD6-UP; 7WR41-UP; 8LL24-UP)

3612 (S/N: 9RC339-UP; 9FR21-UP; 2NZ176-UP)

3616 (S/N: 1PD385-UP; 1FN150-UP)

G3606 (S/N: 3XF264-UP)

G3608 (S/N: 4WF185-UP)

G3612 (S/N: 1YG227-UP)

G3616 (S/N: 4CG238-UP)

Engine News SEBD9298, June 2001, "New Crankshaft Assemblies Include Counterweights That Are Permanently Bolted To The Crankshafts". Disregard this article. This article has been replaced by the following article.

Description of Change: New crankshaft assemblies are used in the 3600 Diesel Engines and the G3600 Gas Engines. The new crankshaft assemblies include counterweights that are permanently bolted to the crankshafts. Formerly, the crankshaft counterweights were welded to the crankshafts. The counterweights are not serviceable components of the new crankshaft assemblies.

Adaptable To: The Table identifies the new crankshaft assemblies and the former crankshaft assemblies. The new crankshaft assemblies are direct replacements for the former crankshaft assemblies. The former crankshaft assemblies are cancelled. The new crankshaft assemblies are effective with the engines that are listed above.

Table 1

Identification of Crankshaft Assemblies
Number of Cylinders	Part Numbers of New Crankshaft Assemblies	Part Numbers of Former Crankshaft Assemblies
6	179-3573	7C-7973
8	193-5845	7C-7974
12	191-5423	7C-7975
16	189-2499	7C-7976

The information that follows is for Vee engines that are equipped with a new crankshaft assembly:

• When you install a connecting rod on the crankshaft, rotate the crankshaft until the counterweights that are adjacent to the crankshaft journal are down.

• When you install a crankshaft main bearing cap, rotate the crankshaft until the counterweights that are adjacent to the crankshaft main bearing are up. This will help prevent interference between the stud tensioner tool group and the counterweights.