D348 VEHICULAR ENGINE Caterpillar


Variable Timing Unit

Usage:



Remove Variable Timing Unit

preparatory step:

a) remove governor

1. Remove the two turbocharger oil drain lines (1) and (2).

2. Remove the variable timing unit cover. Remove drive gear (3) retainer, mounting bolts and lock.

3. Remove the variable timing unit retaining plate, bolts and locks. Remove the variable timing unit.

Install Variable Timing Unit

1. Install the variable timing unit (1). Install the retaining plate, bolts and locks.

2. Install the drive gear, retainer, mounting bolts and lock. Do not tighten mounting bolts.

3. Time the fuel injection pump camshaft to the engine. See FUEL INJECTION PUMP CAMSHAFT TIMING in TESTING AND ADJUSTING.

4. Install the variable timing unit cover. Install the two turbocharger oil drain lines.

concluding step:

a) install governor

Disassemble Variable Timing Unit

preparatory step:

a) remove variable timing unit

1. Drive weight retaining pins from shaft assembly and remove the weights (1).

2. Remove the plug (2). Using a screwdriver, apply pressure and turn retainer (3). Remove the retainer and spring (4).

3. Pull the piston assembly out of shaft assembly.

4. Remove the coupling retaining pin (5). Rotate coupling (6) clockwise and remove from the piston assembly.

5. Remove the nut retaining pin (7). Remove the nut (8), spring (9) and valve (10) from the piston assembly (11).

Assemble Variable Timing Unit

1. Install the valve, spring and nut on piston assembly. Adjust the nut until the distance (X) between bottom face of nut and piston is 1.760 ± .010 in. (44,70 ± 0,25 mm). Drill a .095 ± .002 in. diameter hole through the nut and threaded portion of piston assembly. Install retaining pin.

2. Install the coupling tight against the nut. Measure .156 in. (3,96 mm) from the top face of nut and mark this location on coupling. Drill a .095 ± .002 in. diameter hole through the coupling and threaded portion of piston assembly at this location. Install retaining pin.

3. Install the piston assembly in shaft assembly. Install the retainer and spring. Install plug.

4. Position the weights on shaft assembly and install the retaining pins. Stake the retaining pins at one place on both ends of pin hole in shaft assembly. Each weight must pivot freely on its pin when installed.

concluding step:

a) install variable timing unit

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.