Fuel delivery
Generator Fuel Pump Repairs
The fuel pump moves diesel from the tank toward the engine. A generator that cranks and is not getting fuel can have a weak lift pump, a failed electric pump, a mechanical pump that is not delivering, air in the line, a blocked filter, or contaminated diesel. The pump is not condemned because the engine will not fire, and injection-pump calibration is not part of this visit.
- Supply before the pump is blamed
- Filters and air included
- No injection calibration
- Onsite across Gauteng
Getting diesel to the engine
What does a generator fuel pump do?
A lift pump or feed pump draws diesel from the tank and pushes it through the filters toward the injection equipment. Some sets use an electric pump, some a mechanical one on the engine. If that supply is missing, the engine can crank indefinitely and never fire.
Possible causes include a pump that has weakened, a suction leak letting air in, a blocked filter the pump cannot pull through, water or dirt in the tank, or a shutoff that never opened. Those are tested in that order so a pump is not fitted onto a blocked line.
High-pressure injection pumps are a different component. Where one is suspected, it is diagnosed. It is not calibrated on site as a routine step, and high-pressure lines are not opened as a customer check.
No fuel, weak fuel, dirty fuel
Generator cranks but is not getting fuel
Fuel lift pump faults
The low-pressure pump can spin and still not move enough diesel. Delivery is checked at the filter head, not assumed from the pump noise.
Weak fuel delivery
Enough fuel to idle and not enough to hold load is a different complaint from no fuel at all. Both can be a tired pump or a restriction.
Air in the fuel system
A leaking suction joint lets the pump pull air. The engine then cranks, fires, or dies as the air reaches it. Joints are inspected before the pump is replaced.
Fuel pump versus blocked filter
A new pump on a blocked filter does not restore supply. Filters and the water separator, where fitted, are cleared first.
Fuel contamination
Dirt, water and microbial growth in diesel restrict filters and damage pumps. The tank condition is part of the diagnosis.
How fuel pump problems are diagnosed
Flow or pressure on the low-pressure side, air leaks, filter condition and whether the shutoff is open. The injector page covers spray after fuel has arrived.
Google reviews of ProService Generator Repairs
Google Review
Excellent service for our Vereeniging factory. Their preventative maintenance is unmatched, and they fixed our diesel pump in hours during a fast emergency callout.
Google Review
Very cost-effective servicing for our Ricardo engine. They know exactly how to tune the Ricardo fuel pumps for optimal performance and maximum longevity.
Common Questions
Questions about generator fuel pumps
What does a generator fuel pump do?
It moves diesel from the tank through the filters so the engine can be supplied. Without that delivery the engine can crank and not fire.
The generator cranks but will not start. Is the pump faulty?
It might be. Possible causes also include air, a blocked filter, a closed shutoff and contaminated diesel.
What is a lift pump?
It is the low-pressure pump that lifts diesel from the tank. It is not the high-pressure injection pump.
It runs, then dies when I add load. Can that be fuel delivery?
Yes. A restriction or a weak pump can supply idle and fail when the engine is asked for more fuel.
Do you calibrate injection pumps on site?
No. Low-pressure supply is proved first. Calibration is not a routine or DIY step on this page.
Should I open the injector lines to see if fuel is there?
No. High-pressure diesel is dangerous. Supply is checked on the low-pressure side.
How is a pump fault different from a solenoid fault?
The solenoid allows or cuts fuel. The pump has to move it. A shutoff that never opens leaves a healthy pump with nothing to do.
Still unsure what the fault is? Call or WhatsApp 082 057 4605 for onsite diagnosis.
Service Areas
Onsite visits across Gauteng
Technicians travel to the generator. These are the main Gauteng areas. Suburb pages sit under each region.
What to send before we attend
ProService Generator Repairs confirms an onsite visit from these details. Send what you have. A missing model number does not stop the booking.
- Location
- The suburb or site, so the visit can be booked in the right area.
- Make and model
- The generator brand and model, if they are known.
- kVA
- The size printed on the data plate.
- Fuel type
- Diesel, petrol, LPG, natural gas, or dual-fuel.
- Controller model
- The module name on the panel, when it is visible.
- Fault or alarm
- What the set does, and any text on the screen.
- Photos
- The generator, the data plate, and the controller or alarm. Send these on WhatsApp.
Book a Visit
Say what the fuel is doing
No fuel at the filter, air in the line, or a set that dies under load. Mention if the tank has been contaminated.
- Call
- 082 057 4605
- Message us on WhatsApp