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Perkins 4.108 Engine

General Technical Data

Perkins 4.108 Engine Specifications

Engine Model ............... Perkins 4.108
Engine Type ............... 4-Stroke four-cylinder liquid-cooled diesel
Number of Cylinders ............... 4
Cylinder Arrangement ............... In-line
Engine Bore, in (mm) ............... 3.13 (79.4)
Engine Stroke, in (mm) ............... 3.50 (88.9)
Displacement, cu.in (L) ............... 107.4 (1.76)
Aspiration ............... Naturally aspirated
Rated Engine Power, hp (kW) ............... 37-45 (30-36)
Rated Engine Speed, rpm ............... 3000-3600
Combustion System ............... Indirect injection
Compression Ratio ............... 22.0:1
Firing Order ............... 1-3-4-2
Electrical System Rating, Volts ............... 12

Lubrication System

Oil Pressure ............... 30-60 psi (207-414 kPa)
Oil Capacity ............... 5.1 qts (4.8 L)
Oil Pump ............... Rotor Type
Relief Valve Type ............... Spring Loaded Plunger
Relief Valve Pressure Setting ............... 50-65 psi (345-448 kPa)
Oil Filter Type ............... Full flow, paper canister element

Cooling System

Cooling System Type ............... Water Cooled
Coolant Capacity ............... 7.8 qts (7.4 L)
Thermostat Type ............... Wax Capsule
Water Pump Type ............... Centrifugal, belt driven from Crankshaft Pulley

Fuel System

Injection Pump Type ............... DPA
Injection Pump Model ............... CAV
Lift Pump Type ............... Diaphragm
Lift Pump Drive Method ............... Eccentric on camshaft
Final Fuel Filter Type ............... Paper element

Dimensions and Weight

Overall Width, in (mm) ............... 21.2 (538)
Overall Height, in (mm) ............... 25.2 (639)
Overall Depth, in (mm) ............... 20.1 (508)
Net Weight, lbs (kg) ............... 319 (145)

Perkins 4.108 Maintenance Data

Cylinder Block and Valves

Cylinder Bore Inside Diameter (Maximum), in (mm) ............... 3.1307 (79.520)
Cylinder Head (Max. Out of Flatness), in (mm) ............... 0.003 (0.08)
Intake Valve Clearance, in (mm) ............... 0.012 (0.30)
Exhaust Valve Clearance, in (mm) ............... 0.012 (0.30)

Engine Oil and Filters

Engine Oil Type ............... SAE 30 or 15W-40
Oil Classification ............... API Service CC, CD or CF
Oil Capacity, qts (L) ............... 5.1 qts (4.8 L)
Oil Filter Part Number ............... 2654403
Fuel Filter Part Number ............... 26561117

Service Intervals

Change Engine Oil ............... Every 100 hours
Change Oil Filter Element ............... Every 100 hours
Check Belt Tension ............... Every 100 hours
Replace Final Fuel Filter ............... Every 400 hours
Check and Adjust Valve Clearance ............... Every 400 hours
Service Atomiser ............... Every 400 hours

Perkins 4.108 Service Specifications

Cylinder Block and Liners

Total Height of Cylinder Block between Top and Bottom Faces ..... 9.936-9.939 in (252.374-252.451 mm)
Parent Bore Diameter for Cylinder Liner ............... 3.249-3.250 in (82.525-82.550 mm)
Main Bearing Parent Bore ............... 2.3950-2.3955 in (60.833-60.846 mm)
Camshaft Bore Diameter No.1 ............... 1.794-1.7955 in (45.568-45.606 mm)
Camshaft Bore Diameter No.2 ............... 1.784-1.787 in (45.314-45.390 mm)
Camshaft Bore Diameter No.3 ............... 1.776-1.778 in (45.110-45.161 mm)
Tappet Bore Diameter ............... 0.562-0.56325 in (14.275-14.307 mm)
Fuel Pump Drive Hub Bearing Bore Diameter ............... 1.8125-1.8141 in (46.037-46.078 mm)
Interference Fit of Cylinder Liners ............... 0.003-0.005 in (0.076-0.127 mm)
Inside Diameter of Cylinder Liner after Finish Boring and Honing ......... 3.125-3.126 in (79.375-79.40 mm)
Height of Cylinder Liner in relation to Cylinder Block Top Face ............... 0.023-0.027 in (0.584-0.686 mm)
Overall Length of Cylinder Liner ............... 6.495-6.505 in (164.973-165.227 mm)

Cylinder Head and Valves

Cylinder Head Overall Length ............... 20.000 in (508.000 mm)
Cylinder Head Overall Depth ............... 2.617-2.633 in (66.472-66.878 mm)
Pressure for Water Leakage Test ............... 20 psi (138 kPa)
Cylinder Head Bore for Guide ............... 0.4995-0.5005 in (12.687-12.713 mm)
Cylinder Head Bore for Combustion Chamber Inserts ............... 1.250-1.252 in (31.750-31.801 mm)
Cylinder Head Bore Depth for Combustion Chamber Inserts ........ 0.373-0.376 in (9.474-9.550 mm)
Intake Valve Guide Inside Diameter ............... 0.3141-0.3155 in (7.978-8.014 mm)
Intake Valve Guide Outside Diameter ............... 0.5021-0.5026 in (12.753-12.766mm)
Intake Valve Guide Overall Length ............... 2.130 in (54.102 mm)
Exhaust Valve Guide Inside Diameter ............... 0.3141-0.3155 in (7.978-8.014 mm)
Exhaust Valve Guide Outside Diameter ............... 0.5021-0.5026 in (12.753-12.766 mm)
Exhaust Valve Guide Overall Length ............... 2.440 in (61.98 mm)
Intake Valve Stem Diameter ............... 0.312-0.313 in (7.925-7.950 mm)
Intake Valve Guide To Stem Clearance ............... 0.0011 -0.0035 in (0.028-0.089 mm)
Intake Valve Head Diameter ............... 1.410-1.414 in (35.814-35.916 mm)
Valve Seat Angle ............... 45 deg
Intake Valve Face Angle ............... 45 deg
Intake Valve Overall Length ............... 4.592-4.608 in (116.637-117.043 mm)
Exhaust Valve Stem Diameter ............... 0.3115-0.3125 in (7.912-7.937 mm)
Exhaust Valve Guide To Stem Clearance ............... 0.0016-0.004 in (0.041-0.102 mm)
Exhaust Valve Head Diameter ............... 1.191-1.195 in (30.251-30.353 mm)
Exhaust Valve Face Angle ............... 45 deg
Exhaust Valve Overall Length ............... 4.600-4.616 in (116.840-117.246 mm)
Valve Spring Free Length ............... 1.780 in (45.212 mm)

Crankshaft

Crankshaft Overall Length ............... 21.125 in (536.575 mm)
Crankshaft Main Journal Diameter No.1 and 2 ............... 2.248-2.2485 in (57.099-57.112 mm)
Crankshaft Main Journal Diameter No.3 ............... 2.2475-2.248 in (57.086-57.099 mm)
Crankshaft Main Journal Length No.1 ............... 1.40625 in (35.719 mm)
Crankshaft Main Journal Length No.2 ............... 1.496-1.504 in (37.998-38.202 mm)
Crankshaft Main Journal Length No.3 ............... 1.499-1.502 in (38.075-38.151 mm)
Crankpin Diameter ............... 1.9993-2.0001 in (50.78-50.80 mm)
Crankpin Length ............... 1.1875-1.1895 in (30.162-30.213 mm)
Crankshaft End Float ............... 0.002-0.015 in (0.0508-0.381 mm)
Main Bearing Shell Width ............... 1.245-1.255 in (31.623-31.877 mm)
Main Bearing Outside Diameter ............... 2.3955 in (60.846 mm)
Main Bearing Inside Diameter ............... 2.2505-2.2515 in (57.163-57.188 mm)
Main Bearing Running Clearance (No.1 and 2) ............... 0.002-0.0035 in (0.051-0.089 mm)
Main Bearing Running Clearance (No.3) ............... 0.0025-0.004 in (0.063-0.102 mm)

Pistons and Piston Rings

Overall Height (Skirt to Crown) ............... 3.147-3.150 in (79.934-80.010 mm)
Piston Height in relation to Cylinder Block Top Face ............... 0.002-0.006 in (0.051-0.152 mm)
Bore Diameter for Piston Pin ............... 1.06255-1.06275 in (26.989-26.994 mm)
Piston Pin Outside Diameter ............... 1.0625-1.0627 in (26.987-26.993 mm)
Piston Pin Length ............... 2.673-2.687 in (67.894-68.250 mm)
Top Compression Ring Groove Width ............... 0.0805-0.0815 in (2.045-2.070 mm)
2nd Compression Ring Groove Width ............... 0.0645-0.0655 in (1.638-1.664 mm)
3rd Compression Ring Groove Width ............... 0.0645-0.0655 in (1.638-1.664 mm)
4th Oil Control Ring Groove Width ............... 0.126-0.127 in (3.200-3.225 mm)
5th Oil Control Ring Groove Width ............... 0.190-1.191 in (4.826-4.851 mm)
Top Compression Ring Width ............... 0.0771-0.0781 in (1.958-1.984 mm)
Top Compression Ring Groove Side Clearance ............... 0.0024-0.0044 in (0.061-0.112 mm)
2nd and 3rd Compression Ring Width ............... 0.0615-0.0625 in (1.562-1.587 mm)
2nd and 3rd Compression Ring Groove Side Clearance ............... 0.002-0.004 in (0.051-0.102 mm)
5th Scraper Ring Width ............... 0.1865-0.1875 in (4.737-4.762 mm)
5th Ring Groove Side Clearance ............... 0.0025-0.0045 in (0.063-0.114 mm)
Top Compression Ring End Gap ............... 0.009-0.014 in (0.229-0.356 mm)
2nd and 3rd Compression Ring End Gap ............... 0.009-0.014 in (0.229-0.356 mm)
5th Scraper Ring End Gap ............... 0.009-0.014 in (0.229-0.356 mm)

Connecting Rod

Small End Bush Length ............... 0.935-0.955 in (23.749-24.257 mm)
Small End Bush Outside Diameter ............... 1.221-1.222 in (31.013-31.039 mm)
Small End Bush Inside Diameter before Reaming ............... 1.0495-1.0545 in (26.657-26.784 mm)
Small End Bush Inside Diameter after Reaming ............... 1.06315-1.0632 in (27.004-27.005 mm)
Small End Bush to Piston Pin Clearance ............... 0.00045-0.0007 in (0.0114-0.0178 mm)
Connecting Rod Big End Bore Diameter ............... 2.146-2.1465 in (54.508-54.521 mm)
Connecting Rod Small End Bore Diameter ............... 1.21875-1.21975 in (30.956-30.981 mm)
Length from Centre Line of Big End to Centre Line of Small End ....... 6.217-6.219 in (157.912-157.963 mm)
Connecting Rod End Float ............... 0.0065-0.0105 in (0.165-0.267 mm)
Connecting Rod Bearing Shell Width ............... 0.870-0.880 in (22.098-22.325 mm)
Connecting Rod Bearing Outside Diameter ............... 2.1465 in (54.521 mm)
Connecting Rod Bearing Inside Diameter ............... 2.0015-2.0025 in (50.838-50.863 mm)
Connecting Rod Bearing Running Clearance ............... 0.0015-0.003 in (0.038-0.076 mm)

Camshaft

No.1 Journal Length ............... 1.347-1.351 in (34.214-34.315 mm)
No.1 Journal Diameter ............... 1.791-1.792 in (45.491-45.517 mm)
No.1 Cylinder Block Camshaft Bore Diameter ............... 1.794-1.7955 in (45.568-45.606 mm)
No.1 Journal Running Clearance ............... 0.002-0.0045 in (0.051-0.114 mm)
No.2 Journal Length ............... 1.250 in (31.750 mm)
No.2 Journal Diameter ............... 1.781-1.782 in (45.237-45.263 mm)
No.2 Cylinder Block Camshaft Bore Diameter ............... 1.784-1.787 in (45.314-45.390 mm)
No.2 Journal Running Clearance ............... 0.002-0.006 in (0.051-0.152 mm)
No.3 Journal Length ............... 1.000 in (25.400 mm)
No.3 Journal Diameter ............... 1.773-1.774 in (45.034-45.060 mm)
No.3 Cylinder Block Camshaft Bore Diameter ............... 1.776-1.778 in (45.110-45.161 mm)
No.3 Journal Running Clearance ............... 0.002-0.005 in (0.051-0.127 mm)
Cam Height ............... 0.266 in (6.766 mm)

Perkins 4.108 Tightening Torque Specs

Cylinder Head Nuts, lb-ft (Nm) ............... 60 (81)
Connecting Rod Bolts, lb-ft (Nm) ............... 42 (57)
Main Bearing Bolts, lb-ft (Nm) ............... 85 (115)
Flywheel Bolts, lb-ft (Nm) ............... 60 (81)
Idler Gear Hub Bolts, lb-ft (Nm) ............... 36 (49)
Crankshaft Pulley Bolt, lb-ft (Nm) ............... 150 (203)
Atomiser Securing Nuts, lb-ft (Nm) ............... 12 (16)
Fuel High Pressure Pipe Nuts, lb-ft (Nm) ............... 15 (20)
Dynamo Pulley Nut, lb-ft (Nm) ............... 20 (27)
Alternator Pulley Nut, lb-ft (Nm) ............... 30 (41)
Thermostart Unit, lb-ft (Nm) ............... 10 (13)
Thermostart Insulating Adaptor, lb-ft (Nm) ............... 10 (13)