What the Fuel Injection Pump Actuator (12V / 24V) does
On electronically governed generators, the speed controller reads engine speed from the magnetic pickup and drives an actuator that moves the fuel rack. Together they hold the engine at rated speed — and your supply at 50 Hz — as load changes.
A sticking, worn or failing actuator makes the engine hunt, overspeed on load rejection, or drop speed when load is applied. The actuator must suit both the speed controller and the injection pump linkage.
Signs it needs replacing
- Engine speed hunting up and down; frequency unstable.
- Overspeed or underspeed shutdowns.
- Engine will not reach rated speed, or runs straight to full fuel.
- Actuator coil open-circuit or shorted when tested.
Get the right part first time
Send us these on WhatsApp and our engineers will confirm the exact part before you pay:
- A clear photo of the old part, including any label, stamping or part number on it.
- The make and model of your speed controller.
- A photo of the engine dataplate — the engine serial number decides the exact part.
Fitting notes
The linkage must move freely through full travel without binding; most "actuator" faults are actually a sticky rack or worn linkage. After fitting, the speed controller's gain and stability are tuned with the set on load. Check the magnetic pickup gap and signal at the same time.
Frequently asked questions
Why does my generator hunt?+
Common causes are a sticking fuel rack or linkage, a failing actuator, poor speed-controller settings, or a weak magnetic pickup signal. We test each before replacing parts.
Will any actuator work with my controller?+
No — actuator and controller must be compatible. Send us photos of both and we will match them.
Does the actuator need setting up?+
Yes. Gain and stability are adjusted with the set running on load so speed recovers quickly without hunting.