LB7 injectors are famously unstable. It’s quite often that people have to replace them. But you are probably not one of those people. You are interested in a more hands-on approach and want to deal with the problem at hand yourself. You want to rebuild your diesel injector.
If you are thinking about rebuilding your LB7 injector, then you are in the right place. Here, I will be giving you step by step instructions on how to rebuild LB7 injectors.
But before we learn how to rebuild an LB7 injector. We must first learn why it might fail in the first place.
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Causes of LB7 Injector Failure:
LB7 injectors have a history of having one of the worst failure rates among diesel injectors. There are various reasons why that is. Here are some of the reason for why your LB7 injector might fail:
- Fuel system contamination: Poor maintenance will cause your fuel system to become contaminated with dust, water and other contaminants. Which builds up grime. They are also pumped at a high PSI causing erosion. This in time wears out the injector leading to failure.
- Low lubricity: Low lubricity means that the parts of the LB7 injector are being worn at a faster rate that can lead to damage and eventually failure.
- Over torqued injection halves: This may cause the formation of leaks in your system. Which is never a good thing. That fuel can travel to the crankcase and cause a number of problems.
- Old LB7 injectors: Very old LB7 injectors have a design flaw that causes them to wear out faster than new injectors. Any LB7 injector produced before 2007 has a very specific flaw that causes them to fail faster. The ball seat for sealing the injector is not hardened. As a result, the daily workloads this area faces causes it to erode pretty rapidly.
Newer LB7 injectors do not have that problem as their ball seat is chrome-hardened.
How To Diagnose LB7 Injector Failure?
There are many ways to determine whether your LB7 injector has failed or not.
- Check balance rate: It’s a very simple electronic process. If any of your displayed balance rates exceed 3 mm3 than you probably have a failed LB7 injector.
- Check the crankcase: Check your crankcase for fuel. If you find any then you could be facing leaks in your LB7 injector.
- Use your nose: If your vehicle gives off a smell of unburned fuel when idle than it is an indication that your LB7 injector might be failing.
How To Rebuild LB7 Injectors?
So, now’s the part when we talk about what you really came here for. To rebuild your busted LB7 injector you have to follow a few simple steps. Here’s how you do it –
Step 1: Take it apart
The LB7 injector has 3 parts that you should keep in mind while trying to repair it. The nozzle, the cap, and the injector body. Inside the body, there is a spring. Take an appropriate wrench and rotate the cap to open it. Now, your nozzle is separated from the body. This is the part we are trying to replace. Also, make sure you take out the spring.
Step 2: Clean the injector parts
If you have a diesel injector that needs rebuilding that it’s possible that it has been in use for quite some time now. So, you should expect some dust and grime. You need to clean that. Use pressurized air to clean all of the parts.
Step 3: Reassemble the parts
Take all the separated parts and assembled them just as they were before. Only this time you are going to replace the old nozzle and cap with newly bought ones. Use the wrench to tighten the cap.
Congratulations! You have successfully rebuilt your LB7 injector.
How To Prevent Injector Failure?
Making sure of a few simple things can allow your diesel injectors to last longer. This helps you to avoid going through the hassle of rebuilding your injectors or buying new ones.
- Keep your fuel system clean. A clean fuel system will decrease dust and grime build up in your injectors. Making them last longer.
- Buy good fuel. Cheap fuels can damage your injectors. Shortening their life span.
- Use injector cleaners. Fuel additives are usually not recommended. But it’s good practice to use injector clears from time to time to make sure your LB7 injectors are in top shape.
- Avoid fueling from unreliable sources.
Is It Worth Rebuilding?
Well, it all boils down to what the word ‘worth’ means to you. For many, just the thrill of fixing something instead of opting out for the easier option of ordering online is enough to justify rebuilding the injector.
But from a technical and economic point of view, I have to say no. You see the injector is a very delicate part of the engine. It’s involved with functions that require pinpoint precision. Fixing it yourself in an uncontrolled environment may allow contaminants to enter it. So, you will have to rebuild it again pretty soon.
Then there is the cost. Buying the proper components will cost enough to not justify rebuilding it. And then there is the actual time spent on rebuilding it.
So, the bottom line is, it’s not worth rebuilding. Just buy a new one. But, it’s really not for me to decide what is worth it or not worth it. You are in charge of deciding that.
Thank you for taking the time reading this guide. Hope this helps you out.
How to Rebuild LB7 Injectors (Video Review)