3408 & 3408B DIESEL TRUCK ENGINE Caterpillar


4N8735 Oil Pump (Two Section Gear)

Usage:


NOTICE

Before operation, the pump must be lubricated with clean engine oil and the pump must turn freely by hand or damage to parts can be the result.


Rotation of drive gear (as seen from drive end) ... counterclockwise

NOTE: Make reference to Front Timing Gears to find oil pump drive gear.

Scavenge pump end (Section A)

(1) Diameter of drive shaft and idler shaft (new) ... 20.320 ± 0.005 mm (.8000 ± .0002 in.)

Bore in bearings for drive shaft and idler shaft (new) ... 20.361 ± 0.008 mm (.8016 ± .0003 in.)

(2) Length of gears (new) ... 57.158 ± 0.025 mm (2.2503 ± .0010 in.)

Depth of bores for gears (new) ... 57.285 ± 0.020 mm (2.2553 ± .0008 in.)

Spacer assembly

(3) Diameter of drive shaft and idler shaft (new) ... 22.217 ± 0.005 mm (.8747 ± .0002 in.)

Bore in bearings for drive shaft and idler shaft (new) ... 22.258 ± 0.008 mm (.8763 ± .0003 in.)

Pump body assembly (Section B)

(4) Length of gears (new) ... 79.375 ± 0.025 mm (3.1250 ± .0010 in.)

Depth of bore for gears (new) ... 79.502 ± 0.20 mm (3.3100 ± .0008 in.)

(5) Diameter of drive shaft and idler shaft (new) ... 22.217 ± 0.005 mm (.8747 ± .0002 in.)

Bore in bearings for drive shaft and idler shaft (new) ... 22.258 ± 0.008 mm (.8763 ± .0003 in.)

(6) 2S2760 Spring (oil pressure relief valve):

Length under test force ... 117.9 mm (4.64 in.)

Test force ... 490 ± 27 N (110 ± 6 lb.)

Free length after test ... 152.9 mm (6.02 in.)

Outside diameter ... 27.00 mm (1.063 in.)

(7) Bearing joints (scavenge pump body).

(8) Position of bearing joint from the centerline through bearing bores ... 30 ± 15°

(9) Install bearings in bottom of gear bores to a depth of ... 1.52 ± 0.25 mm (.060 ± .010 in.)


Spacer Assembly

(10) Spacer assembly bearing joints.

(11) Slots must be in location shown when small hole in bearing is aligned with centerline of splash holes (12).

(12) Oil splash holes (lubricating holes).

(13) Install spacer assembly bearings from Face A to a depth of ... 0.76 ± 0.25 mm (.030 ± .010 in.)


Pump Body

(14) Pump body bearing joints.

(15) Position of pump body bearing joint from the centerline through bearing bores ... 30 ± 15°

Install bearings so they are even with outside of pump body.

NOTE: Rotation of pump must be free when turned by hand.

Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.