The Doosan G40 delivers 31 kW of prime power (39 kVA) from a Doosan D24 diesel engine enclosed in the CoolBox acoustically-treated enclosure. At 64 dBA, the G40 matches MQ Power WhisperWatt-class noise levels at a significantly lower price point — typically 15-30% less than comparable CAT portable units.
The 110-gallon integrated fuel tank provides at least 24 hours of runtime at full load. Environmental containment is built into the skid baseframe. The unit is now also sold as the Bobcat PG40 — same internals, different badge.
The D24 is a 2.4-liter naturally aspirated inline-4 diesel — Doosan's mid-range proprietary engine for portable power. Like the smaller D18, it achieves Tier 4 Final compliance through DOC aftertreatment without requiring a DPF, which eliminates regeneration concerns and simplifies maintenance.
The CoolBox enclosure on the G40 integrates sound attenuation, environmental containment, and the 110-gallon fuel tank into a single skid-mounted package. At 64 dBA at 7 meters under full load, the G40 meets noise restrictions on urban construction sites and residential-adjacent projects without supplemental sound barriers.
OnPoint services Doosan G40 units across Northern California rental fleets. The D24 engine shares the same maintenance simplicity as the smaller D18 — no turbo, no DPF, 250-hour oil change intervals. The 110-gallon tank is a genuine advantage for rental operators who want to minimize fuel truck dispatches on multi-day jobs. Fuel filter replacement at 500-hour intervals is the most common service item. Parts availability through Bobcat dealer networks in the Bay Area is reliable, and the CoolBox enclosure panels are straightforward to remove for engine access.
Engineering specifications
Physical
Length
130.5 in
Width
73 in
Height
78.5 in
Wet weight
3,870 lb
Acoustic
Sound @ 7m, full load
64 dBA
Enclosure
Sound-attenuated
Fuel system & runtime
Integral fuel tank
110 gal
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Get pricing & lead time on the Doosan G40
Tell us about the application — kW, voltage, application, install timeline — and we'll respond within one business day with budgetary pricing, lead time, and any sizing notes.
Adjust load percent and tank size to estimate runtime. Pre-filled with this model's spec where available.
Estimate runtime on this tank
Estimated runtime
59.9 hours(2.5 days)
Fuel consumption ≈ 1.84 GPH at 75% load. Estimate based on industry-typical 1800 RPM standby curves (≈0.07 GPH/kW at full load). Actual consumption varies by engine, ambient temperature, fuel quality, and tuning.
Service intervals
Manufacturer-recommended intervals for the Doosan G40 under standby duty. Field intervals may differ based on load profile, ambient conditions, and fuel quality.
Oil & filter
Every 250 hours or 12 months
Air filter
Every 500 hours
Fuel filter
Every 500 hours
Major overhaul
≈ 20,000 hours
Common failure modes
What we've seen fail on this platform. Use as a service-planning reference, not a diagnostic — actual failure modes depend heavily on duty cycle and maintenance history.
Component
Symptom
Typical hours
Severity
Fuel filter
Restricted flow, hard starting, power loss under load
500+
minor
Battery
Failed to start or slow cranking after extended storage
4,380+
minor
Coolant hoses
Weeping at clamp connections, slow coolant loss
5,000+
minor
Frequently Asked Questions
What is the standby power rating of the Doosan G40?
The Doosan G40 delivers 34 kW standby and 31 kW prime power. It uses the Doosan D24 2.4-liter inline-4 engine and is also sold as the Bobcat PG40.
What engine does the Doosan G40 use?
The G40 is powered by a Doosan D24 2.4-liter inline-4 naturally aspirated diesel engine running at 1,800 RPM. Like the D18, the D24 achieves EPA Tier 4 Final compliance through DOC-only aftertreatment with no DPF and no DEF required.
What are the service intervals for the Doosan G40?
Oil changes are due every 250 hours or 12 months, whichever comes first. Air filter and fuel filter replacement intervals are 500 hours. Major engine overhaul is specified at 20,000 hours under normal operating conditions.
Is the Doosan G40 EPA compliant?
Yes. The G40 is EPA Tier 4 Final compliant. The D24 engine meets current emissions requirements through DOC aftertreatment without requiring a DPF, SCR, or DEF — the simplest Tier 4 compliance path available.
How does Doosan compare to CAT at the 40 kVA class?
Both deliver comparable power at 64 dBA noise levels. The G40 typically prices 15-30% below CAT portable units at the 40 kVA class. The D24 engine is a Doosan proprietary platform — parts are available through Doosan/Bobcat dealers, and the engine's naturally aspirated design reduces the number of failure points vs. turbocharged competitors.
What control panel does the Doosan G40 use?
The G40 uses Doosan's integrated digital control panel with auto-start, fault monitoring, and runtime tracking, housed within the CoolBox enclosure for weather protection. The panel provides access to voltage, frequency, and load monitoring for jobsite diagnostics.
Who services Doosan generators in Northern California?
OnPoint Generators services Doosan G-Series portable generators across the Bay Area and Northern California. The D24 engine shares maintenance procedures and parts with the G50, so fleet operators running both models benefit from a single service visit.
Similar models
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