1. What does QSB stand for in Cummins QSB engine?
The full meaning of QSB is Quantum system B. That means that the engine is a family of mid-range engines that were designed for high performance and fuel efficiency.
2. When should the QSB engines be rebuilt?
There are three conditions that determine when to rebuild a QSB engine; operating conditions, maintenance history, and signs of tear and wear of the engine.
In a nutshell, the need to rebuild the engine is usually necessary when the engine performance begins to drop, and also other signs of internal wear.
Ordinary, the QSB engine is usually due for a rebuild after 10,000 – 20,000 hours depending on the applications, load, and other factors.
For example, a QSB used in the marine industry could wear faster.
If you notice these signs, then you should think of overhauling the engine; excessive blow-by, increased oil consumption, loss of power and performance, frequent repairs, strange noises from the engine, and smoking, etc
3. How will I know if the DPF needs to regenerate on the QBS engine?
Depending on the engine and the applications, there are different DPF light indicator on the dashboard or panel controls to tell you when to regenerate.
- a. DPF lamp: You can see the DPF lamp on with the yellow color as a sign to regenerate.
- b. Stop Engine lamp: If you ignore the first light which is the DPF lamp, the Stop Engine’s light will come up telling you about the build-up up soot in the particulate filter.
- c. HEST lamp: This is a sign that the regeneration is now in progress, and the temperature of the exhaust is high. The HEST stands for High Exhaust System Temperature.
4. Can Biodiesel be used on a Cummins QBS engine?
Yes, biodiesel can be used for QSB engines in as much as the fuel is correctly blended. B20 is allowed. The blend should not exceed 20% while the other 80% is petroleum diesel.
But B100 is not allowed on the QSB engine.
The blending must comply with the ASTM D7467 standard.
5. Can the QBS injection pump be converted to a mechanical injection pump?
As you know the QSB is an electronic control engine. However, due to ECM malfunction, you could decide to convert the electronic injection pump to a mechanical injection pump.
There are certain things you need for the changes to go smoothly.
First, you need to replace the front timing case to suit the new injection pump you decide to use. You also need an injection pump, injection pump gear, and other fuel line accessories.
You need to decide the type of pump to use either VE pump or P pump.
With all this info you can convert the QBS injection to a mechanical injection pump.
6. How often should maintenance be performed on QBS engines?
One of the key aspects of prolonging the lifespan of a QSB engine is regular maintenance. These are the maintenance you must be conducting on the engine;
Daily:
Check all the fluid which includes the engine oil, coolant level, and fuel level.
Every 250 Hours:
Change the engine oil and all the filters including the oil filter, air filter, fuel filter
These are the regular maintenance schedules you must not fail to do including the visual inspection of other engine components such as belts, hoses, etc.
7. How does the QSB engine meet emissions standards?
One of the pros of the QSB engines is the ability to meet up with emissions regulations. How?
- a. By employing common rail fuel system: The common rail fuel system delivers fuel at high pressure and with precision timing that eliminates incomplete combustion.
- b. DPF: All the QSB Cummins engines are making use of diesel particulate filters that trap particulate soot and that play a significant role in the reduction of emissions.
- c. EGR: Exhaust gas recirculation is a system in which part of exhaust fumes is cooled and recirculated into the intake air in order to reduce the combustion temperatures. By doing that you have succeeded in lowering the NOx formation which in turn reduces the emissions rate.
8. How to troubleshoot fault code on QSB engines?
There are certain steps you must follow to achieve this.
- i. You need to know the error code that the engine is displaying. All the QSB Cummins engines have a dashboard where you can see the error displayed.
- ii. You need a diagnostic tool that is approved by Cummins such as Cummins Insite, and insert it into the diagnostic port.
- iii. Interpret the fault code by consulting the fault code reference guide.
