3408C, 3412C and 3412D High Performance Marine Engines Caterpillar

Type 1

Illustration 1	g01025602
Typical example

(1) Rear camshaft bearing

The rear camshaft bearing should be flush with the rear face of the pump housing. Tolerance ... ± 0.5 mm (± 0.02 inch)

(2) Middle camshaft bearing ( 3412 engines)

(A) Install the middle camshaft bearing to the following dimension from the front face of the pump housing. ... 175.8 ± 0.3 mm (6.92 ± 0.01 inch)

(3) Install the front camshaft bearing to the following dimension from the front face of the pump housing. ... 0.8 ± 0.5 mm (0.03 ± 0.02 inch)

During installation, the camshaft bearing joints must be located within area (B). Maximum angle to the left or to the right of the vertical centerline ... 10° ± 1°

(4) Install the hollow dowel for the oil outlet to the following dimension from the bottom face of the pump housing. ... 1.5 ± 0.3 mm (0.06 ± 0.01 inch)

(5) Install the hollow dowel for the oil inlet to a maximum dimension from the bottom face of the pump housing. ... 1.0 mm (0.04 inch)

(6) The bearings should be installed in the orientation that is shown. Refer to view A-A in Illustration 1. The bearings must be flush with the front face of the fuel pump housing. Tolerance ... ± 0.5 mm (± 0.02 inch)

Illustration 2	g01024781

(7) Guide pin

(C) Install the injection pump's guide pins to the following dimension. ... 35.57 ± 0.10 mm (1.400 ± 0.004 inch)

Type 2

Illustration 3	g01025102

(1) Two dowels protrude from the rear of the pump housing. Dimension (A) ... 9.7 ± 0.5 mm (0.38 ± 0.02 inch)

(2) The pin protrudes from the top of the pump housing. Dimension (B) ... 4.78 ± 0.25 mm (0.188 ± 0.010 inch)

(3) The dowel protrudes from the top of the pump housing. Dimension (C) ... 12.19 ± 0.25 mm (0.480 ± 0.010 inch)

(4) Fuel rack bearings

The fuel rack bearings are installed into the front of the pump housing. (D) Installation depth ... 19.1 ± 0.5 mm (0.75 ± 0.02 inch) (E) Inside diameter of the fuel rack bearings after installation ... 12.758 ± 0.046 mm (0.5023 ± 0.0018 inch)

(5) Install the hollow dowel for the oil outlet to the following distance from the bottom face of the pump housing. ... 1.5 ± 0.3 mm (0.06 ± 0.01 inch)

(6) Install the hollow dowel for the oil inlet to a maximum distance from the bottom face of the pump housing. ... 1.0 mm (0.04 inch)

(7) Rear camshaft bearing

(F) Install the rear camshaft bearing to the following distance from the rear face of the rear bearing bore. ... 4.8 ± 0.5 mm (0.19 ± 0.02 inch)

(8) Middle camshaft bearing

(H) Install the middle camshaft bearing to the following dimension from the rear face of the rear bearing bore. ... 127.0 ± 0.5 mm (5.00 ± 0.02 inch)

(9) Front camshaft bearing

(G) Install the front camshaft bearing to the following dimension from the front face of the fuel pump housing. ... 1.0 ± 0.5 mm (0.04 ± 0.02 inch)

Inside diameter of the camshaft bearings after installation ... 53.988 ± 0.038 mm (2.1255 ± 0.0015 inch)

Refer to View A-A in Illustration 3.

Locate the camshaft bearing joints in area (K). Maximum angle to the left of the vertical centerline ... 30° ± 1°

Locate the camshaft bearing's oil holes in area (M). Area (M) is located 45° (L) above the horizontal on the right hand side of the fuel pump camshaft's centerline. Maximum angle for area (M) ... 30° ± 1°

Illustration 4	g01035654

(10) Install the shaft to dimension (Q) from the top of the fuel pump housing. Dimension (Q) ... 16.8 ± 0.5 mm (0.66 ± 0.02 inch)

(11) Governor drive bearings

Locate the bearing joints of the governor drive bearings. Refer to View B-B in Illustration 4. Angle (N) ... 10° ± 5°

Install the lower governor drive bearing to the following depth (R) from the top of the fuel pump housing. ... 28.4 ± 0.5 mm (1.12 ± 0.02 inch)

Install the upper governor drive bearing within the following dimension from the top of the fuel pump housing. ... 0.15 mm (0.006 inch)

Inside diameter (P) of the governor drive bearings after installation. Diameter (P) ... 19.093 ± 0.038 mm (0.7517 ± 0.0015 inch)

(12) Cup Plug

Install the cup plug to the following depth (S). ... 1.25 ± 0.25 mm (0.049 ± 0.010 inch)

(13) Fuel rack bearings

Locate the tabs of the fuel rack bearings in the following area.

Use a vertical line through the center of the fuel rack bearing in order to align the center of the bearing tab. Align the center of the bearing tab parallel to the vertical centerline through the center of the fuel pump housing. Tolerance ... 0.05 mm (0.002 inch)

(14) During installation, the pin should be pressed into the bore until contact is made with the bottom of the casting.