Tech Tips: Cummins ISX Camshafts Explained - Dual-Cam, Single-Cam, And Common Failures

Has your camshaft in your ISX failed? Are you looking at an expensive repair? 

We know you want the best option for your Cummins ISX!

Cummins ISX CamThat's why Highway & Heavy Parts carries only the highest quality camshafts for your Cummins ISX engine.

Multiple failure points are associated with the camshafts in this engine, and there are even more if you're running a dual-cam engine.

In this post, we're looking at the changes from a dual-cam to a single-cam setup and what this means for your Cummins ISX.

Click To Talk Directly To A Diesel Engine Expert 8-5 EST

What Are the Features and Benefits of This System?

The Different Versions of the Cummins ISX

Something important to know about the Cummins ISX is that they make two different engines: a dual cam and a single cam. With the single-cam system, though, you have a reduction of failure points in the engine.

The Dual-Cam System

The dual cam is the earlier model. It had one camshaft that operated the valvetrain and another that ran the injectors.

This was an area of heavy wear and created a possible failure point in the engine.

The Single-Cam System

When the engine went to a single cam with a high-pressure injection system, they eliminated this failure point. The load on the injection camshaft was heavier than the load on the valve camshaft because of the design of the injection system and the immense amount of pressure.

Removing this camshaft from the design removed a common point of failure.

Additionally, the design change took a heavy component out of the engine that required a large amount of horsepower to drive it. The single-cam design actually ended up making the engine more efficient. 

Changing to a high-pressure common rail system also allowed the engine to better meet the changing emission standards. And you get more precise timing with this system, increasing your efficiency and fuel economy.


What Are Some Common Failure Points?

As we mentioned, a common failure point on the dual cam engine is the injection cam itself, because you'll get a lot of wear on it.

Injection Cam Failure Points

The injection cam also presented a bit of a problem when it was taken out. It's a unique camshaft, because it's hollow, feeding oil from the inside of the cam.

Debris can build up inside the camshaft, and when it's removed and set on the ground, this buildup can break free. The resulting debris can plug oil holes and cause problems with the cam bearings.

This issue was addressed by the move to the single-cam, high-pressure system.

Issues With Rollers and Rocker Levers

With the dual-cam engine, you'll also see some wear points with the rollers and rocker levers.

On this set up, the injector cam runs a lever, pushing the injector plunger, and actuating the injector itself.

All of these points are opportunities for further wear and failure, whether that be from pitting on the cam or the roller or rollers sliding.

These failure points were similarly removed when the design changed to a single-cam system.

What is the Most Common Failure?

The failure you'll likely see most frequently is the pitting and erosion as a result of the wear from the roller riding on the camshaft.

Oil change intervals are extremely important as well, as extended oil change intervals or coolant dilution into the oil will cause wear on the camshaft and camshaft bearings.

Shop All Cummins ISX Camshafts

Other Important Info About ISX Camshafts

The dual-cam injector camshaft lives its life horizontally. Because oil is fed through the center of the camshaft, it spins.

A lot of companies end up using what's called a centrifugal oil filter. The point of this filter is to use centrifugal force to pull the stuff that's not supposed to be in the filter to the outside.

This results in the oil passages starting to get reduced in size because of the solid buildup. This can result in a spun cam bushing on startup.

When the cam is removed for repairs, a lot of times it is set on end, and even that small impact can cause some of that material to break loose. When it's put back into the engine it can block oil passages, which results in a cam bushing spinning, which ruins the head and the cam. 

To prevent this, though, the soft plug at the end of this particular cam needs to be removed, the inside of the camshaft should be cleaned, and then the plug should be replaced.


Camshaft Installation

We recommend looking at the Cummins service parts topic on the installation of these camshafts. It's important to note the best way to clean the cams, as well as any special tools you might need, like a timing wedge, to help fine tune the engine to run more efficiently.


Highway & Heavy Parts is Here For Your ISX Camshaft Needs!

We're excited to offer the best camshafts for your Cummins ISX engine, including one newly available. 

This cam has induction hardened wear surfaces and refined finish for a performance you just can't beat! Measured with computer-aided testing, you'll be getting precise timing with this camshaft. We only offer the highest quality components for your engine!

Highway & Heavy Parts has a huge selection of parts for your diesel engine, and we source our components from the best manufacturers to ensure you're getting the top quality parts you want.

Our on-staff ASE Certified Technicians can help you quickly analyze and diagnose your engine problem. We work with you to better understand your issue to make sure you're getting the right parts for your application.

All our parts come with an industry-leading warranty, and we can get those components to you fast!

From diagnosis through delivery, we’re Highway and Heavy Parts.

Short On Time? Get Your Quote Online!

Camshaft Resources

Related Articles:



Related Videos:

Give Us A Call!


Short on Time? Take your Quote Online!

We get it- when you need Diesel Engine Parts, time is of the essence. That's why we've developed the HHP Online Quoting System.

Just fill out the form with your name, engine information, and the parts you need, and our ASE-Certified Technicians will get back to you with an estimate. It's as close to magic as a diesel engine gets!

Get A Quote Online!