Specifications
| Fuel | gasoline |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 11 kW |
| Standby kVA | 11 |
| Emissions | EPA |
| Controller | DC2, RDC2 |
| Oil capacity | 1.9 L |
| Alternator | 2F4 (2-pole, Class Class 180 (H) insulation) |
| Voltage options | 120 V, 240 V |
| Phase | 1 |
| Rated current | 45.8 A |
| Power factor | 1.0 |
| Circuit breaker | 60 A |
| Battery group | 51 |
| Battery cranking | 500 CCA |
| Battery voltage | 12 V |
| Battery quantity | 1 |
| Dimensions (L×W×H) | 777×712×824 mm |
| Dry weight | 196 kg |
| Sound level | 67.0 dBA @ 7 m |
Maintenance & consumables
for the Kohler 12RESV engine| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Paper element replacement | — | 150 hr | ||
| Fuel filter | Check flexible lines and connections | — | |||
| Oil filter | — | 100 hr | |||
| Battery | 12 VDC | — | |||
| Belt | null | — | |||
| Oil | 1.9 L | — | 100 hr | ||
| Spark plug | 0.508 (0.020) mm (in.) | — | 500 hr |
Service intervals
18| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Oil level | Check | 8 hr | Before each use and every 8 hours | |
| engine oil level | Check | 8 hr | Check before each use; for extended operation check every 8 hours | |
| Oil | Change | 100 hr | 12 mo | Yearly or 100 hours |
| Oil filter | Replace | 100 hr | 12 mo | Yearly or 100 hours |
| Valve lash (8RESV/L) | Adjust | 100 hr | 100 hours | |
| valve lash (8RESV) | Check | 100 hr | 8RESV models only; requires authorized service | |
| Air cleaner | Replace | 150 hr | 12 mo | Yearly or 150 hours |
| air cleaner | Other | 150 hr | 12 mo | Service more frequently under dusty conditions |
| engine oil and filter | Change | 400 hr | 12 mo | Use 5W-30 synthetic oil |
| Crankcase breather hose | Clean | 500 hr | 12 mo | Yearly or 500 hours |
| Spark plugs | Replace | 500 hr | 12 mo | Yearly or 500 hours |
| Stepper motor coupling and bushing | Replace | 500 hr | 500 hours | |
| Valve lash (10/12RESV/L) | Adjust | 500 hr | 500 hours | |
| valve lash (10/12RESV) | Check | 500 hr | 10/12RESV models only; requires authorized service | |
| Battery cleaner operation | Check | 1 mo | Monthly | |
| Battery electrolyte level | Check | 12 mo | Yearly | |
| Fuel flexible lines | Inspect | 3 mo | Quarterly | |
| battery | Check | 1 mo | Monthly for first year; annually thereafter |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Service specifications
8| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Spark plug gap | Spark plug gap | 0.508 | mm | All models |
| Speed | Frequency regulation steady state | 1.0% | % | |
| Temperature | Carburetor heater thermostat OFF | 16 ± 3 | C (60 ± 5F) | |
| Temperature | Carburetor heater thermostat ON | 4 ± 4 | C (40 ± 7F) | |
| Temperature | Thermostat OFF | 16 ± 3 | °C | Thermostat OFF (60 ± 5°F) |
| Temperature | Thermostat ON | 4 ± 4 | °C | Thermostat ON (40 ± 7°F) |
| Torque | Spark plug installation torque | 24.4 - 29.8 | Nm | Installation |
| Voltage | Voltage regulation (no-load to full-load) | ±1.0% | RMS |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Recommended fluids
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Engine oil | Full Pressure system | 1.9 L | With filter | ||
| Engine oil | 5W-30 | API Service Class SG, SH, or SJ synthetic | Synthetic oil oxidizes and thickens less; recommended for cleaner intake valves and pistons | ||
| Engine oil | 5W-30 API SG/SH/SJ synthetic | API SG/SH/SJ | Synthetic oil recommended | ||
| Fuel | Gasoline | Unleaded gasoline | LP or natural gas capable |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
12RDC2 Voltage Calibration Using SiteTech adjustment
Tools: digital voltmeter, personal computer, SiteTech software
- Connect PC to controller via USB
- With generator off, connect multimeter across L1/L2 (AC volts)
- Start generator set
- Compare voltmeter reading to controller display
- Calculate new Genset Calibration Factor Voltage using (Vmeter / Vcontrol) x Fold = Fnew
- Enter new value into SiteTech and click Apply Changes
- Verify voltmeter matches controller display
- Repeat for L2-L3 and L3-L1 if three-phase
- Press OFF to stop generator set
RDC2 Voltage Calibration Using the Controller Keypad adjustment
Tools: digital voltmeter
- With generator off, connect digital multimeter across L1 and L2, set to AC volts
- Start generator set with RUN button
- Navigate to Generator Metering menu, press Select; Volts L1-L2 displayed
- Press Select; voltage number flashes
- Use up/down arrows to match voltmeter reading
- Press Select to confirm
- Step to Return screen
- Press OFF to stop generator set
VSC Current (Load) Calibration Using the Controller Keypad adjustment
Tools: clamp-on DC current probe or DC current meter
- Connect DC current probe/clamp meter to measure generator current
- Start generator with RUN button
- Adjust system voltage to obtain rated current output with battery bank attached (or use load bank)
- Trip output breaker
- Navigate to Generator Metering menu, select Generator Load
- Press and hold Select for No-Load Calibration; verify breaker open, confirm Yes
- Close output breaker; verify rated output current, confirm Yes
- Verify displayed load is correct; recalibrate if necessary
- Press OFF to stop generator set
Install Carburetor Heater, 17/18/20 kW Models installation
⚠ Accidental starting can cause severe injury or death; disconnect battery cables before working on the generator set, negative lead first.
⚠ Hazardous voltage will cause severe injury or death; disconnect all power sources before opening the enclosure.
⚠ Hot surfaces: disconnect power to the heater and allow it to cool before servicing.
- Open enclosure roof; locate controller and air cleaner.
- Turn off the generator set (master switch or controller OFF button, per model).
- Disconnect AC power to the generator set at the distribution panel breaker.
- Disconnect the starting battery, negative lead first.
- Check nameplate model/spec number and locate heater position per Figure 4.
- Remove the air cleaner cover if needed for access.
- Disconnect the heating element from the power cord at the plug connector.
- Insert the heating element into the threaded opening on the engine and tighten.
- Reconnect the power cord to the heater.
- Route and connect the power cord per the applicable model wiring option (steps 10-12).
- Replace the air cleaner cover if it was removed.
- Affix decal GM22387 onto the air cleaner cover.
- Reconnect the starting battery, negative lead last.
- Reconnect AC power by closing the distribution panel breaker.
- For standby operation, move switch to AUTO and reinstall enclosure panels.
Install Carburetor Heater, Models 8-12RESV/RESVL installation
⚠ Accidental starting can cause severe injury or death; disconnect battery cables before working on the generator set, negative lead first.
⚠ Hazardous voltage will cause severe injury or death; disconnect all power sources before opening the enclosure.
⚠ Hot surfaces: install the heater before connecting it to power; disconnect power and allow it to cool before servicing.
- Open the enclosure roof.
- Press the OFF button on the generator set controller.
- Disconnect AC power to the generator set at the distribution panel breaker.
- Disconnect the starting battery, negative lead first.
- Locate the carburetor heater per Figure 14; remove side panel or air cleaner cover if needed.
- Remove and discard the M8 bolt from the carburetor at the heater location.
- Thread adapter GM91361 into the M8 hole.
- Insert carburetor heater GM57968 into the adapter and tighten.
- Connect the extension cord (GM91360 or 3-way GM95628) to the heater cord.
- Route the cord to the AC receptacle, securing away from throttle linkage and exhaust.
- Plug the cord into the AC receptacle on the generator bulkhead.
- Affix decal GM22387 onto the air cleaner cover.
- Reconnect the starting battery, negative lead last.
- Reconnect AC power by closing the distribution panel breaker.
- Press AUTO for standby operation and reinstall enclosure panels.
Installation Procedure, 17/18/20 kW Models installation
⚠ Disconnect battery cables before working on generator set; remove negative lead first.
⚠ Disconnect all power sources before opening enclosure.
⚠ Install heater before connecting power; allow to cool before servicing.
- Open enclosure roof; locate controller and engine air cleaner.
- Turn off generator set: 17/18RES/RESL move master switch OFF; 20RES/RESL press OFF and remove fuse F3; 20RESA/AL/B/C/CL/D press OFF.
- Disconnect AC power by opening circuit breaker in distribution panel.
- Disconnect engine starting battery, negative lead first.
- Check nameplate model/spec; see Figure 4 for heater location. Heater fits threaded opening on carburetor below air cleaner.
- Remove air cleaner cover if easier access needed.
- Disconnect heater element from power cord at plug connector (GM57968 or GM88228).
- Insert heating element into threaded opening on engine and tighten.
- Reconnect power cord to heater.
- For 17/18RES/RESL and 20RES/RESL: remove air intake panel; install bushing X-634-15 or X-634-16; route cord through bulkhead; plug into 120 VAC receptacle under controller.
- For 120 V 20RESA/AL/B/C/CL/D: route cord away from hot parts; plug into receptacle in engine compartment; use 3-way cord GM95628 if multiple accessories; secure excess cable.
- For 240 V 14/20RESA and 20RESC: remove controller screws, remove bulkhead knockout, route cord and insert plug; disconnect 120 VAC harness at 3-pin; connect 3-pin to new 240 VAC connector.
- Replace air cleaner cover if removed; affix decal GM22387 as shown.
- Check master switch OFF (17/18); reconnect battery, negative last; close distribution breaker. 20RES/RESL: reinstall fuse F3.
- For standby, move master switch to AUTO or press AUTO. Reinstall enclosure panels; close and lock roof.
Installation Procedure, Models 8-12RESV/RESVL installation
⚠ Disconnect battery cables before working on generator set; remove negative lead first.
⚠ Disconnect all power sources before opening enclosure.
⚠ Install heater before connecting power; allow to cool before servicing.
- Open enclosure roof.
- Press OFF button on generator set controller.
- Disconnect AC power by opening circuit breaker in distribution panel.
- Disconnect engine starting battery, negative lead first.
- See Figure 13 for heater location. Remove louvered side panel and/or air cleaner cover for access if necessary.
- Remove and discard M8 bolt from carburetor at heater location.
- Thread adapter GM91361 into M8 hole.
- Insert carburetor heater GM57968 into adapter and tighten.
- Connect extension cord GM91360 or 3-way extension cord GM95628 to heater cord.
- Route cord to AC receptacle as shown; secure with cable ties away from throttle linkage and exhaust.
- Plug cord into AC receptacle on generator bulkhead.
- Affix decal GM22387 onto air cleaner cover.
- Reconnect battery, negative lead last.
- Reconnect AC power by closing circuit breaker.
- For standby, press AUTO. Reinstall enclosure panels; close and lock roof.
Air Cleaner Service (8RESV/RESVL) maintenance
⚠ Do not wash paper element or clean with pressurized air
- Press OFF button and disconnect utility power and battery
- Loosen cover retaining knobs and remove cover
- Remove paper element
- Replace element if dirty, bent, or damaged
- Check air cleaner base for condition
- Check element cover for damage
- Reinstall paper element and air cleaner cover
- Secure cover with retaining knobs
- Reconnect battery and utility power
Firmware Update Using SiteTech maintenance
⚠ Do not load RDC2.4 firmware onto a red- or green-board controller
Tools: personal computer, USB cable, SiteTech software
- Download latest firmware file (.bin) from Kohler Power Resource Center or dealer portal
- Connect controller to PC via USB cable
- Start SiteTech; program recognizes connected device
- Click Update Firmware
- Browse to and select firmware file, click Open
- Verify current/new version and file name, click Update Firmware
- Wait for 'Firmware Updated Successfully' message, click Close
Oil Change Procedure maintenance
⚠ Accidental starting can cause severe injury or death.
⚠ Risk of fire from fuel system.
⚠ Do not smoke near carburetor or fuel system.
Tools: oil filter wrench, funnel, rags, drain pan
- Press OFF button to shutdown generator set.
- Disconnect utility power to generator set.
- Disconnect engine starting battery (negative lead first).
- Remove side panel on exhaust side of enclosure.
- Clean area around dipstick and oil fill cap.
- Cover alternator with rags to prevent oil spillage.
- Insert drain tube onto oil drain valve.
- Open oil drain valve and allow oil to drain completely.
- Close oil drain valve and remove drain tube.
- Clean area around oil filter.
- Loosen oil filter with wrench and remove carefully.
- Clean gasket sealing surface.
- Apply light coat of clean oil to new filter seal.
- Thread new oil filter by hand until resistance, then 3/4 turn more.
- Fill engine with recommended oil to Full mark on dipstick.
Setting the OnCue Password, RDC2 and VSC operation
- Press Select then down arrow to Networking Information menu
- Press Select for Networking Status
- Press Down arrow for Networking Configuration
- Press Select for Reset OnCue Password
- Press and hold Select until 'Reset OnCue Password? No' appears
- Press Up arrow to change No to Yes
- Press Select to reset; serial number and new password display for 10 seconds
Controller Replacement Procedure, Models 14RESA and 20RESA/B/C/D repair
⚠ Do not load settings from a green-board controller onto a red/blue-board controller or vice versa
Tools: voltmeter
- Review service kit information and confirm correct kits
- Open enclosure roof
- Press OFF button, disconnect utility power, verify with voltmeter
- Disconnect starting battery, negative lead first
- Remove two mounting screws, lift controller, disconnect harnesses
- Remove old controller
- If replacing original green-board controller with revised controller, install relay/breaker kit GM95104
- Reconnect harnesses, install new controller, reconnect battery negative last
- Reconnect utility power
- Set date/time/exerciser, update firmware, run Controller Setup and Voltage Calibration
- Replace covers/panels; reset OnCue password if used
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Voltage reconnection
| Voltage | Phase | Connection | Leads | Notes |
|---|---|---|---|---|
| 100/200 | 1 | Single | ||
| 100/200 | 3 | Delta | ||
| 110/220 | 1 | Single | ||
| 110/220 | 3 | Delta | ||
| 115/230 | 1 | Single | ||
| 120 | 1 | Single | Genset System Voltage/Frequency/Phase table for controller setup | |
| 120/208 | 3 | Wye | ||
| 120/240 | 1 | Single | ||
| 120/240 | 3 | Delta | ||
| 127/220 | 3 | Wye | ||
| 220 | 1 | Single | ||
| 220/380 | 3 | Wye | ||
| 230 | 1 | Single | ||
| 230/400 | 3 | Wye | ||
| 240 | 1 | Single | ||
| 240/416 | 3 | Wye | ||
| 277/480 | 3 | Wye |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Common questions
What is the power rating of the Kohler 12RESV?
The Kohler 12RESV is rated 11 kW standby (11.0 kVA).
What engine does the Kohler 12RESV use?
The Kohler 12RESV is powered by the Kohler 12RESV engine engine.
What kind of fuel does the Kohler 12RESV run on?
The Kohler 12RESV runs on gasoline.
What's the oil capacity on a Kohler 12RESV?
The Kohler 12RESV engine engine in the Kohler 12RESV has an oil capacity of 1.9 liters.
What alternator comes on the Kohler 12RESV?
The Kohler 12RESV uses a 2F4 alternator. It has 2 poles. Insulation class Class 180 (H).
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Controller display backlight is off. | Backlight turns off after about 1 minute with no activity. | Backlight will turn on when a button is pressed or the generator set starts. |
| Controller display is off. | Low or no battery voltage. | Check connections. Check generator set battery. |
| The generator set does not crank. | Battery weak or dead. | Recharge or replace the battery. |
| Fault shutdown. | Check the controller display for fault messages. See Section 2.5. Correct the fault condition and reset the controller. | |
| Generator set in the OFF mode. | Press the RUN button to start the engine or press AUTO to allow remote starting. | |
| Gererator thermostat tripped. | For trips other than temperature (nuisance trips), | Reset the thermostat. See Section 2.6. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Kohler 12RESV troubleshooting guide (8 entries) →
Parts
4| Part # | Description | Qty | System | |
|---|---|---|---|---|
| GM80980 | Brush(es) | 1 | Brush | Amazon eBay |
| GM62996 | Adapter plate | 1 | Service part / kit | Amazon eBay |
| GM80981 | Brush holder | 1 | Service part / kit | Amazon eBay $19.50 |
| GM80982 | Shim | 1 | Service part / kit | Amazon eBay |
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.
Fuel consumption
| Rating | Load | L/h | gal/h |
|---|---|---|---|
| Exercise | 100% | 2.1 | 0.55 |
| Standby | 3.4 | 120.0 | |
| Standby | 25% | 10.22 | 2.7 |
| Standby | 50% | 12.87 | 3.4 |
| Standby | 75% | 15.52 | 4.1 |
| Standby | 100% | 19.31 | 5.1 |
Available documents
Spec sheet (Kohler)Spec sheet — Kohler.12RESV.Spec.g4241 (Kohler)Spec sheet — Kohler.12RESVL.SPECS.g4242 (Kohler)Operator's manual (Kohler)Reference (Kohler)Reference — 21-03R Air-Cooled Residential Product Updates - 2021 (Kohler)Reference — RES Consumer Referral Rebate (Kohler)Reference — ReferralRebateForm Editable1 (Kohler)Reference — Referral Rebate Form EDITABLE (Kohler)Reference — Rotor Stator Reading Form (Kohler)Reference — g4254 (Kohler)Reference — tp6984fr (Kohler)Owner's manual — tp6880 (Kohler)Owner's manual — tp6880fr (Kohler)Parts manual (Kohler)Parts manual — Kohler 2017 Referral Rebate Consumer RES (Kohler)Parts manual — Kohler 2019 RES Consumer Referral Rebate (Kohler)Parts manual — tt1589 (Kohler)Service manual — Controllers tt1589 (Kohler)Service manual — TT-1482 (Kohler)Service manual — tp6879 (Kohler)Service manual — tp6984 (Kohler)Service manual — tt1482 (Kohler)Service manual — tt1619 (Kohler)Service manual — tt1634 (Kohler)