Mitsubishi S12A2 User Manual

6-1
Chapter 6 INSPECTION AND REPAIR OF BASIC ENGINE
1. Cylinder Head and Valve Mechanism - Inspect and Repair.................................6-3
1.1 Bushing Inside Diameter and Shaft Outside Diameter of Rocker - Measure............................ 6-3
1.2 Rocker Bushing - Replace........................................................................................................6-3
1.3 Valve Stem Outside Diameter and Valve Guide Inside Diameter - Measure ........................... 6-4
1.4 Valve Guide - Replace..............................................................................................................6-4
1.5 Valve Face - Inspect................................................................................................................. 6-5
1.6 Valve Face - Reface ................................................................................................................. 6-5
1.7 Valve Seat - Reface.................................................................................................................. 6-6
1.8 Valve Seat - Replace................................................................................................................ 6-6
1.9 Valve and Valve Seat - Lap ......................................................................................................6-8
1.10 Valve Bridge, Bridge Cap, Valve Cotter and Valve Rotator - Inspect....................................... 6-8
1.11 Squareness and Free Length of Valve Spring - Measure......................................................... 6-9
1.12 Tappet - Inspect........................................................................................................................ 6-9
1.13 Push rod Runout - Measure...................................................................................................... 6-9
1.14 Nozzle Gland Stud Bolt and Bridge Guide - Inspect and Replace............................................ 6-9
1.15 Distortion of Cylinder Head Bottom Surface - Measure.......................................................... 6-10
1.16 Water Director - Inspect and Replace..................................................................................... 6-10
2. Rear Mechanism - Inspect and Repair.................................................................6-11
2.1 Idler Bushing Inside Diameter and Idler Shaft Outside Diameter - Measure.......................... 6-11
2.2 Idler Bushing - Replace .......................................................................................................... 6-11
2.3 Cam Lift of Cam Shaft Lobe - Measure .................................................................................. 6-11
2.4 Camshaft Runout - Measure...................................................................................................6-12
2.5 Camshaft Journal Outside Diameter - Measure ..................................................................... 6-12
2.6 Camshaft Bushing - Inspect.................................................................................................... 6-12
2.7 Camshaft Bushing - Replace.................................................................................................. 6-13
3. Front Mechanism - Inspect and Repair................................................................6-14
3.1 Damper - Inspect Visually.......................................................................................................6-14
3.2 Pulley - Inspect ....................................................................................................................... 6-14
4. Piston and Connecting Rod - Inspect and Repair ..............................................6-15
4.1 Piston - Inspect Visually.......................................................................................................... 6-15
4.2 Piston Weight ......................................................................................................................... 6-15
4.3 Piston Outside Diameter - Measure........................................................................................ 6-15
4.4 Piston Ring Groove - Inspect..................................................................................................6-15
4.5 Piston Pin Bore Inside Diameter - Measure............................................................................ 6-16
4.6 Piston Ring - Inspect Visually .................................................................................................6-16
4.7 Piston Ring End Gap - Measure............................................................................................. 6-16
4.8 Piston Pin Outside Diameter - Measure ................................................................................. 6-16
4.9 Connecting Rod Bushing Inside Diameter - Measure............................................................. 6-17
4.10 Connecting Rod Bushing - Replace........................................................................................ 6-17
4.11 Connecting Rod Assembly Weight Rank................................................................................ 6-20
4.12 Bore Diameter and Roundness of Connecting Rod Big End - Measure................................. 6-20
4.13 Side Face Width of Connecting Rod Big End - Measure........................................................ 6-21
4.14 Connecting Rod Big End Serration and Bolt Holes - Inspect.................................................. 6-21
4.15 Connecting Rod Bearing - Inspect.......................................................................................... 6-21
4.16 Connecting Rod Bearing Thickness - Measure ...................................................................... 6-22
4.17 Connecting Rod Bend and Twist - Inspect ............................................................................. 6-22

Mitsubishi S12A2 Specifications

General

Brand	Mitsubishi
Model	S12A2
Category	Engine
Language	English