Specifications
Ratings spec sheet not in our library yet — see the documents below.
Maintenance & consumables
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | — | 500 hr | find | ||
| Fuel filter | — | 1000 hr | find | ||
| Oil filter | — | 500 hr | find | ||
| Belt | — | find | |||
| Coolant | Change coolant every 2,500 hours or as needed. Add coolant as necessary. | — | 2500 hr | ||
| Coolant filter | — | find | |||
| Oil | — | 500 hr |
Troubleshooting
5Symptoms & remedies
| Symptom | Remedy |
|---|---|
| The generator set starts during normal power service | 1. The operation selector switch on the generator set control panel should be set at Remote. 2. Check the exerciser clock to see if it is in an exercise period. When the exerciser clock is in an exercise period, a '1' appears in the upper right-hand corner of the display window (Figure 7-1). You can view the display by looking through the transparent clock cover. |
| The operation selector switch on the generator set control panel should be set at Remote. | Check the exerciser clock to see if it is in an exercise period. When the exerciser clock is in an exercise period, a '1' appears in the upper right-hand corner of the display window (Figure 7-1). You can view the display by looking through the transparent clock cover. Check that the red slide switch is in the center position. |
| Visual and audible evidence of exhaust system leaks. | Shut down the GenSet and repair any detected leaks. |
| Fuel, oil, or coolant leaks on the GenSet. | Shut system down and have leaks repaired before use. |
| PRIORITY GENERATOR SET FAILS, BUT BACKUP GENERATOR SET DOES NOT START | 1. Two-wire starting only (for water-cooled generator sets): Check the generator set. The operation selector switch on the generator set control panel should be in the Remote position. Check for fault indicators on the generator set control. 2. Three-wire starting only (for air-cooled generator sets): The Auto/Stop/Handcrank switch on the 3-Wire Start modules should be in the Auto position. Check for overcrank condition. (See Operation Section). 3. Start the generator set using its start-stop controls. (The Auto/Stop/Handcrank switch on the 3-Wire Start module must be in the Handcrank position.) If it does not crank, check the starting battery. If it cranks but does not start, check the fuel supply. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Parts
56| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 626-1763 | OT III Schematic/Wiring Diagram | Wiring diagram | buy | |
| 800-0092 | Screw, Cap - Hex Head (1/2-13 x 1.5) | 2 | Screw | buy |
| ES1692 | 2-AMP CHARGER | 1 | Battery | buy |
| SC1583 | PROGRAM TRANSITION MODULE | Program transition module | buy | |
| SC1584 | SIGNAL MODULE | Signal module | buy | |
| SC1613 | 10-AMP CHARGER | 1 | Battery | buy |
| SCI579 | SLIDE SWITCH | Switch | buy | |
| SCI583 | PROGRAM TRANSITION MODULE | Module | buy | |
| SCI584 | SIGNAL MODULE | Module | buy | |
| 300-3998 | ALARM MODULE | Service part / kit | buy | |
| 301-6179 | Wrapper | 1 | Service part / kit | buy |
| 301-6217 | Window | 1 | Service part / kit | buy |
| 301-6297 | Base 111 ,1,~,’ ;: : 98-4447 98-4447 98-4447 1 Silkscreen | 1 | Service part / kit | buy |
| 305-2532 | 1 | Service part / kit | buy | |
| 306-1038 | *Barrier, Chute - Arc | 2 | Service part / kit | buy |
| 306-1041 | 4 | Service part / kit | buy | |
| 306-2266 | See Tab 1 See Tab Tab 306-2357 | 2 | Service part / kit | buy |
| 306-2274 | 4 | Service part / kit | buy | |
| 306-2340 | Barrier | 1 | Service part / kit | buy |
| 306-2532 | 815-0449 8 ~26-0CJ08 | 1 | Service part / kit | buy |
| 306-2554 | I 1 3“+------- I1 1...—–—–.———-—. ._—.\.. .–.– —--%——— -—-– —----— --------–-—––—-\--– 11 \ 5 !l? | 14 | Service part / kit | buy |
| 306-2978 | 1 | Service part / kit | buy | |
| 308-0406 | Switch, Toggle - DPDT Harness, Wiring - Main Standard 60 Hertz | 1 | Service part / kit | FridayParts $18.00 |
| 315-0004 | Transfnrmer(-05) 315-0014 315-0014 1 ‘I’ransfOrmer (-06) 1 ‘I’ransfOrmer (-03) 1 Transformer(-04) 315-0036 315-0036 1 TransfOrmer(-05) 315-0 | 1 | Service part / kit | buy |
| 323-1201 | Connector-Plug Housing | 1 | Service part / kit | FridayParts $339.85 |
| 323-1208 | Strain Relief 1 CONTACT lj~ 308”05’79 (Normal Open) BLOCK 308-05630 (Normal Closed) (IT —. n/ —.-—— TERMINAL FLOCK 2 R m ,! 1, 4Yl m -1 REF. | 2 | Service part / kit | buy |
| 332-0795 | Block, Terminal -16 Place | 1 | Service part / kit | buy |
| 332-2133 | Stand Off-Insulator | 3 | Service part / kit | buy |
| 332-2440 | Lug-Solderlesfi 4 a | 3 | Service part / kit | buy |
| 332-2445 | Lug-SOlderLess | 3 | Service part / kit | buy |
| 332-2448 | Stancl Off-Insulatcr ~ 850-0050 3 Washer-LK(3/8) | 2 | Service part / kit | buy |
| 337-1051 | Neutral Bar | 1 | Service part / kit | buy |
| 518-0341 | Compound-Joint (Elec) | 1 | Service part / kit | buy |
| 524-0157 | Tab Tab | 4 | Service part / kit | buy |
| 526-0003 | #Washer, Flat (#8) | 4 | Service part / kit | buy |
| 526-0008 | *Washer, Flat (#10) | 1 | Service part / kit | buy |
| 526-0018 | Gasket, Flange (1-3/4) | 1 | Service part / kit | FridayParts $1002.50 |
| 612-6490 | GenSet AC Diagram | Service part / kit | buy | |
| 612-6538 | GenSet DC Diagram | Service part / kit | buy | |
| 800-0019 | 4 | Service part / kit | buy | |
| 800-0030 | Screw, Cap - Hex'Head (5/16-18 X 1-1/4') | 1 | Service part / kit | buy |
| 800-0047 | Screw-HHC(3/8-16x5/8) | 1 | Service part / kit | buy |
| 800-0051 | Screw-H}iC(3/8-16xl 1/4) | 1 | Service part / kit | buy |
| 800-0052 | Screw | 2 | Service part / kit | buy |
| 800-0089 | Screw-HliC(l/2-13x7/8) | 3 | Service part / kit | buy |
| 800-0185 | *Screw, Cap - Hex Head (1/4-20 x 5-1/2) | 4 | Service part / kit | buy |
| 800-C030 | 2 | Service part / kit | buy | |
| 815-0540 | 2 | Service part / kit | buy | |
| 850-0011 | 860-0003 2 See Tab | 2 | Service part / kit | buy |
| 850-0020 | Washer, Lock - Spring (#6) | 2 | Service part / kit | buy |
| 850-0060 | Screw, Cap - Hex Head (5/16-18 X 7-1/2" ) | 4 | Service part / kit | buy |
| 851-0022 | Conical Disc Spring(3/8) [+ 337-1050 1 Neutral Bar | 3 | Service part / kit | buy |
| 851-0023 | Washer | 2 | Service part / kit | buy |
| 853-0003 | Washer, Lock - ET (#6) | 4 | Service part / kit | buy |
| 862-0003 | Nut, Hex (3/8-16) | 1 | Service part / kit | buy |
| SCI279-1 | Transfer Switch Installation Manual | Service part / kit | buy |
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 |
|---|---|---|---|
| Prime | |||
| Standby |
Available documents
Operator's manual — 962-0116 Cummins CN CT ON OT 40-1000A Operators Manual (4-2013) (Cummins/Onan)Operator's manual — 962-0117 Onan OT III 40-1000A Remote Operators Manual (6-1993) (Cummins/Onan)Reference — s-1548 (Cummins/Onan)Parts manual — 962-0219 Cummins OT III OT-ON CT-CN 150-260 Parts (8-2001) (Cummins/Onan)Parts manual — 962-0220 Cummins OT III 300-40-600 Parts (5-2014) (Cummins/Onan)Service manual — 962-0512 Onan OT III (spec G-H) 40 to 1000 Amp Transfer Switch Service manual (06-2001) (Cummins/Onan)