MAINTENANCE

SECTION MA
CONTENTS
ENGINE MAINTENANCE .................................. MA-2 Maintenance Schedule ...................................MA-8
Specifications .................................................MA-2 Oil and Grease, and Capacity ........................MA-9
Tightening Torque ..........................................MA-6 On Board Inspection and Service .................MA-10
 ENGINE MAINTENANCE

ENGINE MAINTENANCE Specifications

INSPECTION AND ADJUSTMENT
• Oil capacity H line: 2(Imp qt)
3.7 (3-1/4)
• Oil capacity L line: 2 (Imp qt)
2.7 (2-3/8)
• (Oil filter capacity): 2(Imp pt)
0.3 (1/2)
• Fan belt deflection [When pressed by a force of approximately
10 kg (22 lb)] : mm (in)
Standard 11 - 13 (0.43 - 0.59)
• Compression: kPa (bar, kg/cm2, psi)/rpm
Standard 1,275 (12.7, 13.0, 185)/250 (K15)
1,226 (12.3, 12.5, 178)/250 (K21)
1,275 (12.7, 13.0, 185)/250 (K25)
• Difference between each cylinder: kPa (bar, kg/cm2, psi)/rpm
Repair limit 98 (0.98, 1.0, 14)/300
• Spark plug gap : mm (in)
Standard 0.8 - 0.9 (0.31 - 0.35)
• Distributor (Full transistor type) air gap : mm (in)
Standard 0.35 - 0.45 (0.0138 - 0,0177)
• Valve clearance (Hot) : mm (in)
Standard Intake: 0.38 (0.0150)
Exhaust: 0.38 (0.0150)
• Thermostat valve opening temperature (STD): °C (°F)
Standard 76.5 (170)
• Idle speed and ignition timing (BTDC°/rpm)
Standard 0/700±50 (K15)
0/700±50 (K21)
0/700±50 (K25)
2/700±50 (K21, carburetor specification)
0/700±50 (other than above)

CYLINDER HEAD
• Cylinder head : mm (in)
Material Aluminum alloy
Distortion limit 0.1 (0.004)

CYLINDER BLOCK
• Block upper surface : mm (in)
Distortion limit 0.1 (0.004)
• Bore diameter dimension : mm (in)
Standard 75.50 - 75.55 (2.9724 - 2.9744) (K15)
89.00 - 89.05 (3.5039 - 3.5059) (K21, K25)
• Bore diameter wear : mm (in)
Repair limit 0.2 (0.008)
• Bore diameter out-of-round : mm (in)
Standard 0.02 (0.008) or less
• Bore diameter taper : mm (in)
Standard 0.02 (0.008) or less
• Bore diameter out-of-round and taper : mm (in)
Repair limit 0.1 (0.004)

MA-2
ENGINE MAINTENANCE

Specifications (Cont’d)
PISTON
• Piston : mm (in)
Type Thermal flow type
Material Aluminum alloy
Outer diameter Standard 75.465 - 75.515
(2.9711 - 2.9730) (K15)
88.965 - 89.015
(3.5026 - 3.5045) (K21) (K25)
• Gap between piston and cylinder : mm (in)
Standard 0.025 - 0.045 (0.0010 - 0.0018)
(Selective fit service parts)
• Piston pin outer diameter : mm (in)
Standard 19.993 - 19.998 (0.7871 - 0.7873)
(K15, K21, K25)
• Piston pin fitting quality
Standard To a degree allowing movement by hand
• Piston ring end gap : mm (in)
Standard Top 0.28 - 0.43
(0.0110 - 0.0169)
Second 0.45 - 0.60
(0.0177 - 0.0236)
Oil 0.20 - 0.60
(0.0079 - 0.0236)
Various limit values 1.00 (0.0394)
• Gap between piston ring and ring groove : mm (in)
Standard Top 0.045 - 0.080
(0.0018 - 0.0031)
Second 0.030 - 0.070
(0.0012 - 0.0028)
Oil 0.65 - 0.135
(0.0256 - 0.0053)
Repair limit Top 0.10 (0.0039)
Second 0.10 (0.0039)
Oil -

CONNECTING ROD
• Distance between both end hole centers : mm (in)
Standard 143.970 - 144.030 (5.6681 - 5.6811) (K25)
152.470 - 152.530 (6.0027 - 6.0051)
(K15, K21)
• Large end hole diameter : mm (in)
Standard 48.0 - 48.013 (1.8898 - 1.8903)
(K15, K21, K25)
• Small end hole diameter : mm (in)
Standard 19.965 - 19.978 (0.7860 - 0.7865)
(K15, K21, K25)
• Bend (per 100 mm) : mm (in)
Repair limit 0.05 (0.0020)
• Torsion (per 100 mm) : mm (in)
Repair limit 0.05 (0.0020)
• Large end thrust gap
Standard 0.2 - 0.3 (0.0079 - 0.0118)
Repair limit 0.40 (0.0157)

MA-3
ENGINE MAINTENANCE

Specifications (Cont’d)
• Large end oil clearance : mm (in)
Standard 0.030 - 0.066 (0.0012 - 0.0026)
(K15, K21, K25)
Repair limit 0.10 (0.0039)
• Difference of weight (Piston combination): g (oz)
Standard4 (0.14) or less

CRANKSHAFT
• Bend : mm (in)
Repair limit 0.05 (0.0020)
• End play : mm (in)
Standard 0.05 - 0.18 (0.0020 - 0.0071)
Repair limit 0.20 (0.0079)
• Journal dimension : mm (in)
Standard 62.942 - 62.955 (2.4780 - 2.4785)
• Pin standard dimension : mm (in)
Standard 44.961 - 44.974 (1.7701 - 1.7706)
(K15, K21, K25)
• Journal oil clearance : mm (in)
Standard 0.020 - 0.073 (0.0008 - 0.0029)
Repair limit 0.10 (0.0039)
• Pin oil clearance : mm (in)
Standard 0.032 - 0.066 (0.0013 - 0.0026)

FLYWHEEL
• Flywheel surface swing : mm (in)
Repair limit 0.10 (0.0039)
• Ring gear surface swing : mm (in)
Repair limit 0.50 (0.0197)
• Flatness : mm (in)
Repair limit 0.30 (0.0118)

CAMSHAFT
• Bend : mm (in)
Repair limit 0.05 (0.0020)
• Camshaft height : mm (in)
Standard 36.750 - 36.800 (1.4468 - 1.4488)
(For both intake and exhaust)
Size reduction limit 36.5 (1.437)
• Journal dimension : mm (in)
Standard Front 45.434 - 45.447 (1.7887 - 1.7892)
Center 43.897 - 43.910 (1.7318 - 1.7287)
Rear 41.218 - 41.231 (1.6228 - 1.6233)
• End play : mm (in)
Standard 0.025 - 0.255 (0.0010 - 0.0100)
Repair limit 0.40 (0.0157)
• Journal oil clearance : mm (in)
Standard Front 0.025 - 0.051 (0.0010 - 0.0020)
Center 0.038 - 0.064 (0.0015 - 0.0025)
Rear 0.025 - 0.051 (0.0010 - 0.0020)
Repair limit Front 0.10 (0.0039)
Center 0.15 (0.0059)
• Journal oil clearance : mm (in)
Repair limit Rear 0.10 (0.0039)

MA-4
ENGINE MAINTENANCE

Specifications (Cont’d)
VALVE
• Head outer diameter : mm (in)
Standard Intake 38.0 - 38.3 (1.496 - 1.508)
Exhaust 32.0 - 32.3 (1.260 - 1.272)
• Valve stem outer diameter : mm (in)
Standard Intake 6.97 - 6.985
(0.2744 - 0.2750)
Exhaust 6.945 - 6.960
(0.2734 - 0.2740)
• Valve guide inner diameter : mm (in)
Standard Intake 7.0 - 7.018 (0.2756 - 0.2763)
Exhaust 7.0 - 7.018 (0.2756 - 0.2763)
• Gap between valve stem and valve guide : mm (in)
Standard Intake 0.020 - 0.053
(0.0008 - 0.0021)
Exhaust 0.040 - 0.073
(0.0016 - 0.0029)
Repair limit Intake 0.10 (0.0039)
Exhaust 0.10 (0.0039)
• Gap between valve lifter and lifter guide : mm (in)
Standard 0.016 - 0.052 (0.0006 - 0.0020)
• Gap between crankshaft and flywheel : mm (in)
Standard 0 - 0.038 (0 - 0.0015)
• Gap between rocker shaft and rocker arm : mm (in)
Standard 0.020 - 0.054 (0.0008 - 0.0021)
• Valve clearance (Hot) : mm (in)
Intake 0.38±0.03 (0.0150±0.0012)
Exhaust 0.38±0.03 (0.0150±0.0012)

MA-5
 ENGINE MAINTENANCE

Tightening Torque
Upper: Lubricated (Antirust oil is applied to abrasive faces of
threads and seating faces)
Lower: No lubrication (Threads and seating faces are
completely degreased)
Thread size
Unit 4T (Bolt) 7T (Bolt) 9T (Bolt)
Diameter Pitch
N·m 3.8 - 4.4 6.4 - 7.5 9.2 - 10.8
kg-m 0.39 - 0.45 0.65 - 0.76 0.94 - 1.1
ft-lb, in-lb* 34 - 39* 56 - 66* 82 - 95*
M6 1
N·m 5.0 - 6.5 8.4 - 10.8 11.8 - 15.7
kg-m 0.51 - 0.66 0.86 - 1.1 1.2 - 1.6
ft-lb, in-lb* 44 - 57* 75 - 95* 9 - 12
N·m 9.3 - 10.8 15.7 - 17.7 22.6 - 25.5
kg-m 0.95 - 1.1 1.6 - 1.8 2.3 - 2.6
Hexagon head bolt and nut

ft-lb, in-lb* 82 - 95* 12 - 13 17 - 19

M8 1.25
N·m 12.7 - 15.7 20.6 - 26.5 29.4 - 37.3
kg-m 1.3 - 1.6 2.1 - 2.7 3.0 - 3.8
ft-lb, in-lb* 9 - 12 15 - 20 22 - 19
N·m 19.6 - 22.6 32.4 - 38.2 47.1 - 53.9
kg-m 2.0 - 2.3 3.3 - 3.9 4.8 - 5.5
ft-lb, in-lb* 14 - 17 24 - 28 35 - 40
1.25
N·m 25.5 - 33.3 43.1 - 54.9 61.8 - 78.5
kg-m 2.6 - 3.4 4.4 - 5.6 6.3 - 8.0
ft-lb, in-lb* 19 - 25 32 - 41 46 - 58
M10
N·m 18.6 - 21.6 30.4 - 36.3 44.1 - 52
kg-m 1.9 - 2.2 3.1 - 3.7 4.5 - 5.3
ft-lb, in-lb* 14 - 16 22 - 27 33 - 38
1.5
N·m 24.5 - 31.4 41.2 - 52 58.8 - 74.5
kg-m 2.5 - 3.2 4.2 - 5.3 6.0 - 7.6
ft-lb, in-lb* 18 - 23 30 - 38 43 - 55
N·m 4.9 - 5.69 8.14 - 9.51 11.8 - 13.7
kg-m 0.5 - 0.58 0.83 - 0.97 1.2 - 1.4
ft-lb, in-lb* 43 - 50* 72 - 84* 9 - 10
M6 1
N·m 5.98 - 7.65 9.81 - 12.7 14.7 - 18.6
kg-m 0.61 - 0.78 1.0 - 1.3 1.5 - 1.9
ft-lb, in-lb* 53 - 68* 87 - 113* 11 - 14
N·m 11.8 - 13.7 19.6 - 23.5 28.4 - 33.3
kg-m 1.2 - 1.4 2.0 - 2.4 2.9 - 3.4
ft-lb, in-lb* 9 - 10 14 - 17 21 - 22
M8 1.25
N·m 14.7 - 18.6 24.5 - 31.4 35.3 - 45.1
kg-m 1.5 - 1.9 2.5 - 3.2 3.6 - 4.6
Flanged bolt

ft-lb, in-lb* 11 - 14 18 - 23 26 - 33
N·m 24.5 - 29.4 41.2 - 48.1 59.8 - 69.6
kg-m 2.5 - 3.0 4.2 - 4.9 6.1 - 7.1
ft-lb, in-lb* 18 - 22 30 - 35 44 - 51
1.25
N·m 30.4 - 39.2 51.0 - 64.7 73.6 - 93.2
kg-m 3.1 - 4.0 5.2 - 6.6 7.5 - 9.5
ft-lb, in-lb* 22 - 29 38 - 48 54 - 69
M10
N·m 23.5 - 27.5 39.2 - 46.1 56.9 - 65.7
kg-m 2.4 - 2.8 4.0 - 4.7 5.8 - 6.7
ft-lb, in-lb* 17 - 20 29 - 34 42 - 48
1.5
N·m 29.4 - 37.3 49.0 - 61.8 69.6 - 89.2
kg-m 3.0 - 3.8 5.0 - 6.3 7.1 - 9.1
ft-lb, in-lb* 22 - 27 36 - 46 51 - 48

CAUTION:
Except special nuts and bolts.
The bolts applicable to this table have one of the following marks
embossed on their heads.
4T......4
7T......7
9T......9

MA-6
ENGINE MAINTENANCE

Tightening Torque (Cont’d)

Tightening point Unit Standard Max. value

Cylinder head (lubricated) Refer to MA-10.

Crankshaft pulley bolt (lubricated) N·m 220.5 240.1
kg-m 22.5 24.5
ft-lb, in-lb* 163 177
Oil filter element N·m 14.7 20.6
kg-m 1.5 2.1
ft-lb, in-lb* 11 15
Spark plug N·m 19.6 29.4
kg-m 2.0 3.0
ft-lb, in-lb* 14 22
Engine slinger bolt N·m 22.6 25.5
kg-m 2.31 2.6
ft-lb, in-lb* 16.7 19
Rocker cover nut N·m 13.7 15.7
kg-m 1.4 1.6
ft-lb, in-lb* 10 12
Water temperature gauge N·m 15.7 19.6
kg-m 1.6 2.0
ft-lb, in-lb* 12 14
Oil pressure switch N·m 15.7 21.6
kg-m 1.6 2.2
ft-lb, in-lb* 12 16
Exhaust manifold nut Refer to MA-10.
Oil pan drain plug N·m 29.4 39.2
kg-m 3.0 4.0
ft-lb, in-lb* 22 29
Crankshaft position sensor plug bolt N·m 6.37 7.45
kg-m 0.65 0.76
ft-lb, in-lb* 56* 66*
Thermo-housing air relief plug N·m 6.37 7.45
kg-m 0.65 0.76
ft-lb, in-lb* 56* 66*

MA-7
 ENGINE MAINTENANCE

Maintenance Schedule
Make sure to perform appropriate maintenance and service work to
maintain the initial performances of the NISSAN forklift.

PERFORM INSPECTION
Make sure to perform the periodical inspections at appropriate
times, according to the month basis or the operating hour basis,
whichever comes first. ...... Inspection period

Refer to the following notes for values in ( )

Engine system inspection (except LPG fuel system)

Applicable Months of use 1 2 3 4 5 6 7 8 9 10 11 12

Inspection items
No. control Operation hours
system 2 4 6 8 10 12 14 16 18 20 22 24
(x 100 hours)
1 Intake/exhaust valve clearance Electronic A A A A A
controls,
carburetor
2 Engine drive belt tension Electronic I I I I I I I I I I I I
controls,
carburetor
3 Cylinder head bolt and manifold nut Electronic T
controls,
carburetor
4 Engine oil Electronic (1) R´ R´ R´ R´ R´
controls,
carburetor
5 Oil filter Electronic (1) R´ R´ R´ R´ R´
controls,
carburetor
6 Engine coolant Electronic R
controls,
carburetor
7 Fuel filter Carburetor (1) C C C C C
8 Air cleaner element Electronic C C C C C C C C C C C C
controls,
carburetor
9 Engine idle speed Carburetor A A A A A A A A A A A A
10 Ignition timing Carburetor A A A A A A A A A A A A
11 Spark plug Electronic I I I I I I I I I I I I
controls,
carburetor
12 Ignition nozzle Electronic I I I I I
controls
13 Distributor (point, cap, and rotor) Carburetor I I I I I I I I I I I I
14 Distributor (inside) Carburetor (1) C
15 PCV valve Electronic (1) I I I I
controls,
carburetor
16 PCV hose Electronic I I I I
controls,
carburetor

MA-8
 ENGINE MAINTENANCE

Maintenance Schedule (Cont’d)

Engine system inspection (LPG models)

Applicable Months of use 1 2 3 4 5 6 7 8 9 10 11 12

No. Inspection items control
Operation hours
system 2 4 6 8 10 12 14 16 18 20 22 24
(x 100 hours)
1 Gas leakage from piping and piping Electronic (2) I I I I I I I I I I I I
joints controls,
carburetor
2 Damage to piping and piping joints Electronic I I I I I I I I I I I I
controls,
carburetor
3 Tar in vaporizer Electronic D D D D D D D D D D D D
controls,
carburetor
4 Ignition nozzle Electronic I I I I I
controls
5 LPG filter Electronic C C C R
controls,
carburetor

CAUTION:
• (1) The maintenance work should be performed more
frequently if the vehicle is being used in dusty and dirty
environments.
• (2) Apply soap suds to the piping joints to check for any
gas leakage after replacing the LPG tank.
Meanings of symbols:
I = Inspection. Repair or replace if necessary.
R = Replacement
A = Adjustment
C = Cleaning
D = Draining
T = Tightening (Retightening)
R' = Replacement [Every 500 hours
(3 months)] Engine oil, oil filter

Oil and Grease, and Capacity

OIL, LLC
Items Specification Remarks

Engine oil Gasoline *10W-30 (Class SJ) Refer to SAE viscosity index. (SE, SH can be used.)
Antifreeze Genuine NISSAN long life coolant

* It is the oil for filling in at factory.

FILLING CAPACITY (GUIDELINE) Unit: 2(Imp qt)

Items Capacity

Engine oil K15 3.7 (3-1/4) (including filter)

K21 3.7 (3-1/4) (including filter)
K25 3.7 (3-1/4) (including filter)

MA-9
 ENGINE MAINTENANCE

On Board Inspection and Service

TIGHTENING OF HEAD BOLT
Tighten head bolts from inside to outside as shown in the figure.
Tighten bolts gradually as shown in the figure.
Tightening torque: 68.6 N·m (7.0 kg-m, 51 ft-lb) (This tightening
torque can be used in step (5) as shown in the figure for service.)

CAUTION:
Check tightening angle with an angle wrench (SST) or a
protractor. Do not simply estimate tightening angle.

MAM0147

RETIGHTENING OF MANIFOLD NUT AND BOLT

CAUTION:
Do not retighten nut and bolt until manifold components get
cold. It may cause to get burned.

Tightening torque for manifold and nut

Models N·m kg-m ft-lb

K15 41.2 - 48.1 4.2 - 4.91 30.4 - 35.5

K21 41.2 - 48.1 4.2 - 4.91 30.4 - 35.5
K25 41.2 - 48.1 4.2 - 4.91 30.4 - 35.5

(Do not use power tools such as air runner to tighten.)

INTAKE/EXHAUST VALVE CLEARANCE ADJUSTMENT

• Adjustment must be made with the vehicle in hot condition.
1. Warm up engine until engine coolant temperature gauge shows
nearly center, and then stop it.
2. Remove rocker cover.
3. Turn the crankshaft.

CAUTION:
Disconnect high-tension cable from ignition coil when rotating
crankshaft with starter motor.

MA-10
 ENGINE MAINTENANCE

On Board Inspection and Service (Cont’d)

4. Set the piston for the No. 1 cylinder to the compression TDC
and adjust the valves of (1), (2), (3), and (5) in the figure.
5. Set the piston for the No. 4 cylinder to the compression TDC by
rotating crank again and adjust the valves of (4), (6), (7), and (8)
in the figure.

Intake/exhaust valve clearance (Hot) Unit: mm (in)

Models Intake Exhaust

K15 0.38 (0.015) 0.38 (0.015)

MAM0143 K21 0.38 (0.015) 0.38 (0.015)
K25 0.38 (0.015) 0.38 (0.015)

INSPECTION AND ADJUSTMENT OF ENGINE DRIVE BELT

CAUTION:
Make sure that engine stops. Wash hands.
1. Visually check fan belt for wear, damage, and cracks. Do not
contact the belt with pulley groove bottom.
2. Push the belt between pulleys. Check tension.
Belt deflection: 11 - 13 mm (0.43 - 0.51 in)
Force: 98 N (10 kg, 22 lb)

ETM0046

REPLACEMENT OF OIL AND OIL FILTER

1. Warm engine.
2. Remove oil pan drain plug and oil filler cap, and discharge all oil.

CAUTION:
• Be careful not to get burned when engine or engine oil is
heated.
• It shows the mixing of coolant so that oil looks likes milk.
Repair if necessary.
• It shows the mixing of gasoline so that oil viscosity is too
lean. Repair if necessary.
3. Wipe around drain hole. Install drain plug.
Tightening torque for oil pan drain plug:
29.4 - 39.2 N·m (3.0 - 4.0 kg-m, 22 - 29 ft-lb)

MA-11
 ENGINE MAINTENANCE

On Board Inspection and Service (Cont’d)

4. Replace oil filter.
• Remove oil filter using an oil filter wrench (SST).
• Wipe oil filter mounting surface with a clean shop cloth.

MAM0144

• Apply a small amount of engine oil to the lip of the new oil filter.

MAM0145

• Screw in the oil filter by hand until it contacts cylinder block

boss, and then screw in another 2/3 of a turn.

MAM0146

5. Fill the oil according to the specified lubricant amount.

Standard oil amount Unit: 2 (Imp qt)

Including filter 3.7 (3-1/4)
Not including filter 3.4 (3)

6. Start engine, and make sure that there is no leakage around

drain plug and oil filter. Replace drain plug and oil filter if there is
some leakage.
7. Run engine, and stop it after engine coolant temperature gauge
is in nearly center position. Check oil level after waiting for a few
minutes. Refill oil if necessary.

MA-12