Onan MDKBU Service Manual

10-2
MDKBP MDKBR MDKBS
ALTERNATOR: Single-Bearing, Brushless 4-Pole Rotating Field with Digital Electronic Regulation. See Genset Nameplate for Rating.
FUEL CONSUMPTION:
60 Hz: Full Load
Half Load
1.3 gph (4.9 liter/hr)
0.8 gph (3.0 liter/hr)
1.9 gph (7.2 liter/hr)
1.1 gph (4.2 liter/hr)
2.5 gph (9.5 liter/hr)
1.5 gph (5.7 liter/hr)
50 Hz: Full Load
Half Load
1.1 gph (4.2 liter/hr)
0.7 gph (2.7 liter/hr)
1.6 gph (6.1 liter/hr)
0.9 gph (3.4 liter/hr)
2.1 gph (8.0 liter/hr)
1.3 gph (4.9 liter/hr)
ENGINE: Kubota 4-Stroke Cycle, Indirect Injection, Water Cooled Diesel with Digital Electronic Governing
Model V1903B V2203B V2803B
Number of Cylinders 4 4 5
Displacement 113.37 in
3
(1857 cm
3
) 134.07 in
3
(2197cm
3
) 167.57 in
3
(2748 cm
3
)
Bore 3.15 in (80 mm) 3.43 in (87 mm) 3.43 in (87 mm)
Stroke 3.64 in (92.4 mm) 3.64 in (92.4 mm) 3.64 in (92.4 mm)
Compression Ratio 23:1 23:1 23:1
Firing Order (Clockwise Rotation) 1-3-4-2 1-3-4-2 1-3-5-4-2
Fuel Injection Timing 14.5° BTDC 16° BTDC 16° BTDC
Valve Lash (cold)
0.0071 − 0.0087 in
(0.18 − 0.22 mm)
0.0071 − 0.0087 in
(0.18 − 0.22 mm)
0.0071 − 0.0087 in
(0.18 − 0.22 mm)
Lube Oil Capacity 8 quart (7.6 liter) 8 quart (7.6 liter) 12.7 quart (12 liter)
Lube Oil Drain Connection 3/8 NPT 3/8 NPT 3/8 NPT
Coolant Capacity 8 quart (7.6 liter) 8 quart (7.6 liter) 8 quart (7.6 liter)
Coolant Flow Rate: 60 Hz
50 Hz
14.0 gpm (53.0 liter/min)
10.0 gpm (37.9 liter/min)
14.0 gpm (53.0 liter/min)
10.0 gpm (37.9 liter/min))
14.0 gpm (53.0 liter/min)
10.0 gpm (37.9 liter/min)
Raw Water Flow Rate: 60 Hz
50 Hz
9.0 gpm (34.1 liter/min)
7.0 gpm (26.5 liter/min)
9.0 gpm (34.1 liter/min)
7.0 gpm (26.5 liter/min)
9.0 gpm (34.1 liter/min)
7.0 gpm (26.5 liter/min)
Combustion Air Flow: 60 Hz
50 Hz
52 cfm (1.45 m
3
/min)
42 cfm (1.21 m
3
/min)
60 cfm (1.72 m
3
/min)
50 cfm (1.43 m
3
/min))
75 cfm (2.12 m
3
/min)
63 cfm (1.78 m
3
/min)
Heat Rejection to Ambient: 60 Hz
50 Hz
350 Btu/min (88 kcal/min)
285 Btu/min (72 kcal/min)
420 Btu/min (106 kcal/min)
350 Btu/min (88 kcal/min)
530 Btu/min (134 kcal/min)
450 Btu/min (114 kcal/min)
Maximum Angularity 10° Continuous, 22.5° Intermittent
Recommended Fuel No. 2-D Diesel Fuel: Spec EN 590 or ASTM D975
Recommended Coolant
Ethylene Glycol: Spec ASTM D5345 for 50/50 Prediluted Coolant or
ASTM D4985 for Concentrated Coolant with 40% to 60% quality water
CONNECTIONS:
Max Fuel Pump Lift 4 ft (1.2 m) 4 ft (1.2 m) 4 ft (1.2 m)
Fuel Supply 1/4 NPT female 1/4 NPT female 1/4 NPT female
Fuel Return 1/4 NPT female 1/4 NPT female 1/4 NPT female
Max Raw Water Pump Lift 4 ft (1.22 m) 4 ft (1.22 m) 4 ft (1.22 m)
Raw Water Inlet 1 in (25.4 mm) ID Hose 1 in (25.4 mm) ID Hose 1 in (25.4 mm) ID Hose
Wet Exhaust Outlet 2 in (50.8 mm) ID Hose 2 in (50.8 mm) ID Hose 2 in (50.8 mm) ID Hose
Dry Exhaust Outlet 1-1/2 NPT 1-1/2 NPT 1-1/2 NPT
Max Exhaust Back Pressure 3 in (76 mm) Hg 3 in (76 mm) Hg 3 in (76 mm) Hg
KEEL COOLING:
Coolant Inlet & Outlet 1 in (25.4 mm) ID Hose 1 in (25.4 mm) ID Hose 1 in (25.4 mm) ID Hose
Max Coolant Friction Head 1 psi (6.9 kPa) 1 psi (6.9 kPa) 1 psi (6.9 kPa)
Heat Rejection to Coolant: 60 Hz
50 Hz
1590 Btu/min (402 kcal/min)
1500 Btu/min (379 kcal/min)
1980 Btu/min (500 kcal/min)
1670 Btu/min (422 kcal/min)
2490 Btu/min (629 kcal/min)
2090 Btu/min (528 kcal/min)
Thermostat Opening Temperature 185° F (85° C) 185° F (85° C) 185° F (85° C)
BATTERIES:
Nominal Battery Voltage 12 volts (24 volts optional) 12 volts (24 volts optional) 12 volts (24 volts optional)
Min CCA Rating − SAE @ 32° F (0° C) 500 amps 625 amps 625 amps
Battery Charging @ 12/24 VDC 40/20 amps 40/20 amps 40/20 amps
SIZE, WEIGHT, NOISE:
Without Enclosure
Dry Weight
Dimensions: L x W x H
830 lbs (377 kg)
44.4 x 23.7 x 26.1 in
(1127 x 602 x 663 mm)
870 lbs (375 kg)
44.4 x 23.7 x 26.1 in
(1127 x 602 x 663 mm)
1090 lbs (494 kg)
53.5 x 23.7 x 28.8 in
(1358 x 602 x 732 mm)
With Enclosure
Noise
Dry Weight
Dimensions: L x W x H
67/64 dB(A) @ 60/50 HZ
890 lbs (404 kg)
44.4 x 23.7 x 27.5 in
(1127 x 602 x 698 mm)
67/64 dB(A) @ 60/50 HZ
930 lbs (422 kg)
44.4 x 23.7 x 27.5 in
(1127 x 602 x 698 mm)
68/67 dB(A) @ 60/50 HZ
1175 lbs (533 kg)
53.5 x 23.7 x 30.0 in
(1358 x 602 x 763 mm)
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Onan MDKBU Specifications

General

Brand	Onan
Model	MDKBU
Category	Portable Generator
Language	English