Cummins Injector

How to Rebuild a Cummins Injector

July 14, 2022 8:51 pm Published by Leave your thoughts

Like other diesel engines, Cummins motors today and for a number of years already rely on fuel injectors for delivery of fuel and air to the combustion chamber inside the engine. Built to be durable and handle the industrial load of a commercial hauling engine like Cummins diesel motors, these fuel injectors last for a significant lifetime over regular vehicle fuel injectors. However, even industrial grade equipment needs maintenance and eventual replacement.

What is a Cummins Injector?

Similar to fuel injectors for other automotive engines, a Cummins injector provides fuel injection mixing specific to a Cummins diesel engine. The assembly is matched to the engine need for standard operation, with the appropriate parts and tuning to run at an optimum efficiency of fuel supply and consumption.

An Injector Rebuild is a Specific Process

A Cummins fuel injector rebuild essentially involves the removal, cleaning, and examination of all the parts of the individual fuel injector assembly. Those parts that are consumable or showing wear, such as cracking and failure, are replaced entirely with new stock. Those that are durable and long-lasting, such as the injector casing, are cleaned out thoroughly and prepared for use again. Then, the entire rebuilt assembly is re-installed back into the engine, connected, tested, and verified as working properly for regular use and driving.

Life Expectancy Decisions Happen

At a certain point with extensive life, a Cummins fuel injector rebuild is really a decision about whether the injector should be rebuilt again or entirely replaced. After too much wear and use, the assembly simply needs to be swapped out with an entirely new build, usually at the point of recommended life by the manufacturer. Aside from tracking the date of original installation, the actual failure and replacement date isn’t known or possible to correctly estimate until the assembly is removed from the engine and examined by a trained technician. In most cases, brand new fuel injectors are warrantied to last two to three years, and rebuilt units from a manufacturer have a one-year warranty and life expectancy.

The Steps to Expect in a Fuel Injector Rebuild

The rebuild process, as mentioned above, first involves the disconnecting and removal of the fuel injectors from a Cummins engine. While it is possible to clean fuel injectors in place, they cannot be properly evaluated for damage or leakage when installed. Removal is a necessary step for any kind of a rebuild. With the assembly removed, it is then disassembled on a workbench and cleaned. Any old parts that are always replaced in a rebuild are disposed of with new stock ready to add and utilize. After cleaning, durable parts are fully examined. At this point a critical evaluation is made by the technician, whether the fuel injector in question is can be rebuilt at all or should be entirely replaced. The secondary choice is to then decide whether to use a new assembly or a rebuild kit from the manufacturer. While the rebuild kit is lower in cost, it doesn’t last as long until the next service is needed.

A fuel injector rebuild service goes through a specific checklist needed to verify a professional maintenance service completion. That includes the following in many cases:

  • Full disassembly and cleaning
  • Spring replacement
  • Valves being reseated as well as tested under pressure
  • Any bearings involved being replaced, including bearing supports
  • Internal seal replacement
  • Internal O-ring replacement
  • New hardware such as crush washers are replaced and installed
  • Full operational testing to factory specifications prior to the vehicle being returned to operating service

Using Rebuild Kits and Reliance on Tuning

Typically, two out of three rebuild kits need some kind of tuning by a trained technician to run correctly, which also includes having the right tooling to do the related work as well. So, while a fuel injector rebuild can be done independently, the value of a professional service is repeatedly seen in the combination of reliable service, extensive experience and skill, replacement stock being in inventory, and having the correct tooling available to complete the job per manufacturer specifications.

How to Clean Cummins Injectors Without Removing Them

If just a cleaning is needed, injectors can be kept in place and instead flushed with a cleaning solvent. This involves disconnecting the fuel line, injecting a solvent with a pressure delivery, and then flushing out the solvent with a reconnection running the engine. While a cleaning will improve performance for a while, it will not address any repair needs that are resolved when a rebuild is applied instead.

Cummins Injection Cleaning Service

Cummins injector rebuild service can also provide help with a cleaning service as well. The advantage of using a service versus trying to apply the cleaning directly is that the professional approach uses the right tools as well as takes care of all the disposal involved as well. And when your vehicle equipment is worth hundreds of thousands of dollars, as well as every day’s worth of trucking income, the last thing anyone wants to do is jeopardize it with an amateur repair mistake. For more information on how to rebuild a Cummins injector, contact Thompson Diesel.

Categorised in:

This post was written by admin

Leave a Reply

Your email address will not be published. Required fields are marked *