80 kW Tier 4 Final diesel commercial standby generator. John Deere-powered diesel with EPA Tier 4 Final emissions compliance for commercial and institutional applications.
The Kohler 80REOZJ4 is an 80-kilowatt EPA Tier 4 Final diesel commercial standby generator powered by a John Deere engine at 1800 RPM. It is certified for both stationary emergency and non-emergency applications and features a brushless rare-earth permanent-magnet alternator with Fast-Response excitation, sustained short-circuit capability up to 300% for 10 seconds, a durable sound-attenuating steel housing rated at 71 dB(A) at 7 meters, and integrated environmental containment.
OnPoint services John Deere-powered Kohler diesel generators across Northern California. The 80REOZJ4 shares the REOZJ platform with the 100REOZJF and 125REOZJG, giving us strong parts commonality and technician expertise across the mid-range diesel lineup.
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
38.9 hours(1.6 days)
Fuel consumption ≈ 4.94 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 Kohler 80REOZJ4 under standby duty. Field intervals may differ based on load profile, ambient conditions, and fuel quality.
Oil & filter
Every 250 hours or 12 months
Coolant change
Every 3000 hours
Air filter
Every 500 hours
Fuel filter
Every 500 hours
Major overhaul
≈ 15,000 hours
Load bank test
Every 12 months
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
DEF system (SCR catalyst)
Derate warning, NOx fault, DEF quality alert
4,380+
moderate
Fuel quality / degradation
Injector fouling, hard starting, filter clogging
4,380+
moderate
Turbocharger
Power loss, excessive smoke under load
12,000+
moderate
Battery (starting)
Failed to start, slow crank
8,760+
minor
Frequently Asked Questions
What engine is in the Kohler 80REOZJ4?
The 80REOZJ4 uses a John Deere diesel engine, turbocharged and aftercooled, rated at 1800 RPM with EPA Tier 4 Final emissions certification.
What is the sound level of the 80REOZJ4?
Per Kohler specifications, the 80REOZJ4 is rated at 71 dB(A) at 7 meters at full load with the sound-attenuating steel housing.
Does the 80REOZJ4 include environmental containment?
Yes. The unit includes a 125% environmental containment basin for oil/coolant and a UL 142 listed subbase fuel tank for 24-hour runtime at prime rating.
