“The generator will not start” describes several very different failures. The controller may never issue a crank command, the starter may turn too slowly, or the engine may crank normally without firing. Preserving the first sequence avoids replacing parts by guesswork.
Engineering decisions covered
Facility teams reporting an automatic-start failure to remote or on-site support.
Classify the failure before any reset: no crank, slow crank or normal crank with no firing.
A fault timeline that separates control, starting circuit, cranking speed and fuel or engine causes.
Classify the failure before any reset: no crank, slow crank or normal crank with no firing.
Decision 01
Did the controller command the engine to crank?
A missing crank command can result from mode selection, emergency stop, active shutdown, interlock, ATS signal or control-power loss. These causes must be separated from a starter-motor problem.
Record controller mode, start source, alarm history and the exact event sequence before reset.
- Photograph the first alarm screen
- Confirm auto, manual and emergency-stop state
- Record whether the crank relay was commanded
- Preserve ATS and remote-start events
Decision 02
If it cranks slowly, where is the voltage being lost?
Low battery capacity, loose terminals, cable resistance, poor ground, cold conditions or a damaged starter can all reduce speed. Standing voltage alone cannot identify the cause.
Capture minimum battery voltage and rpm during one controlled crank attempt.
- Record battery model, age and temperature
- Measure cranking voltage under load
- Inspect cables, lugs and engine ground
- Stop repeated attempts that heat the starter
Decision 03
If cranking speed is normal, why may the engine not fire?
Fuel shutoff state, air in the line, empty day tank, blocked filter, failed transfer pump or loss of speed signal can prevent firing. Recent fuel or maintenance work is important evidence.
Document tank level, visible valve state, filter history and any recent work without opening pressurized systems.
- Confirm available fuel and day-tank alarms
- Record transfer-pump status
- Report recent filter or line work
- Note smoke or absence of smoke while cranking
Decision 04
What makes a useful remote-diagnosis package?
A complete package lets the engineer see what changed, what the controller decided and how the mechanical system responded. A description such as “it does nothing” cannot support a safe decision.
Send one timeline with photos, readings, video and actions already taken.
- Include nameplate and controller model
- List alarms in time order
- Attach one start-attempt video with sound
- State every reset or part already changed
Do not bridge terminals, bypass safeties or repeat long crank cycles. Batteries, starters, fuel and moving parts create serious hazards; internal testing requires qualified personnel.
Decision record
Separate Site Evidence from Engineering Confirmation
Use traceable site data and a named engineering check to support each decision; specialist calculations remain with the qualified design or service team.
| Decision Point | Prepare on Site | Confirm in Design or Service |
|---|---|---|
| Did the controller command the engine to crank? | Photograph the first alarm screenConfirm auto, manual and emergency-stop state | Record whether the crank relay was commandedPreserve ATS and remote-start events |
| If it cranks slowly, where is the voltage being lost? | Record battery model, age and temperatureMeasure cranking voltage under load | Inspect cables, lugs and engine groundStop repeated attempts that heat the starter |
| If cranking speed is normal, why may the engine not fire? | Confirm available fuel and day-tank alarmsRecord transfer-pump status | Report recent filter or line workNote smoke or absence of smoke while cranking |
| What makes a useful remote-diagnosis package? | Include nameplate and controller modelList alarms in time order | Attach one start-attempt video with soundState every reset or part already changed |
Project record
The Review Should Leave a Usable Project Record
Record the verified condition, engineering conclusion, responsible party and retest or acceptance result for each topic.
Did the controller command the engine to crank?
Record controller mode, start source, alarm history and the exact event sequence before reset.
If it cranks slowly, where is the voltage being lost?
Capture minimum battery voltage and rpm during one controlled crank attempt.
If cranking speed is normal, why may the engine not fire?
Document tank level, visible valve state, filter history and any recent work without opening pressurized systems.
What makes a useful remote-diagnosis package?
Send one timeline with photos, readings, video and actions already taken.