Engine Failure Archives

Posted on October 11, 2025April 30, 2026 by David Ley

Diagnosing a Bad Cummins ISX Crankshaft: Symptoms and Replacement

The crankshaft is essentially the backbone of your truck’s engine. It keeps the engine moving and is vital to the overall health of your rig. When this critical component begins to fail in a Cummins ISX, it can quickly lead to severe mechanical damage and costly downtime. Recognizing the early warning signs of a worn or damaged crankshaft is essential to minimizing negative impacts to your revenue and keeping your truck out of the service bay.

Posted on September 15, 2025April 30, 2026 by David Ley

Cylinder Head Bolt Stretch vs Torque: Why Your Head Gasket Keeps Failing

When a head gasket fails, most people look at the gasket.

But in many diesel engines, the real issue isn’t the gasket at all: it’s improper clamp load caused by incorrect bolt stretch.

If clamp load isn’t correct or consistent across the cylinder head, combustion pressure will find a way out.

This is where understanding bolt stretch vs. torque becomes critical.

Posted on September 15, 2025April 30, 2026 by David Ley

What Problems Indicate Head Gasket Failure on C15 ACERT Diesel Engines?

We all know that the head gasket is important. It’s what creates the seal between the engine block and cylinder head to allow for combustion to happen. Without it, your diesel engine won’t run properly.

Posted on September 15, 2025April 30, 2026 by David Ley

Problems That Require Cylinder Head Components for the CAT C15 ACERT Diesel Engine

You may not realize it, but there are a lot of components that make up the cylinder head of your C15 ACERT. If you have a failure in that part of your engine, you might be inclined to blame it on your cylinder head, but it’s possible that one of these other components could break. This would lead to problems with similar symptoms to that of a failing cylinder head.

Posted on September 15, 2025April 30, 2026 by David Ley

Camshaft Failure Analysis: What Causes Excessive Lobe Wear (C15 Focus Included)

We all know how important camshafts are to engine performance – and when they fail, the damage can go far beyond the camshaft itself.

Whether you’re running a general diesel platform or a Caterpillar C15 diesel engine, one of the most common issues is camshaft lobe wear and pitting.

👉 And once it starts, it does not slow down – it accelerates.

Posted on August 3, 2025April 30, 2026 by David Ley

Cummins N14 Cylinder Head: Failure Points, Internal Stress, and What Happens When It Starts to Go

The Cummins N14 is built to handle heat and load – but the cylinder head is where those forces concentrate the most.

Over time, repeated thermal cycling, combustion pressure, and coolant flow stress begin to break things down at a microscopic level.

And when that happens, the issue usually doesn’t show up as “a bad head.”

It shows up as:

Coolant Loss
Overheating
Combustion Imbalance

By the time it’s obvious, the damage is already progressing.

Posted on July 6, 2025April 30, 2026 by David Ley

Cummins ISX, QSX Cylinder Head: Symptoms, Failure Causes, and Replacement Guide

If your Cummins ISX or QSX is overheating, losing coolant, or showing signs of combustion issues, the problem may be deeper than a gasket or sensor.

It could be your cylinder head.

And when a cylinder head starts to fail, it doesn’t take long before it affects the entire engine.

Posted on June 26, 2025April 30, 2026 by David Ley

Caterpillar C15, 3406E Camshaft: Symptoms, Failure Causes, and Replacement Guide

If your Caterpillar C15 or 3406E isn’t running like it used to – losing power, misfiring, or making unusual noise – the problem might not be what you think.

It could be your camshaft.

And if that’s the case, waiting too long can turn a manageable repair into a full engine rebuild.

Posted on June 26, 2025April 30, 2026 by David Ley

Caterpillar 3406E Camshaft: Symptoms, Failure Causes, and Replacement Guide

If your Caterpillar 3406E is losing power, popping through the intake, or backfiring through the exhaust, the problem may not be fuel-related at all. In many cases, those symptoms point back to camshaft or valve train wear. When those components start to fail, performance can drop quickly, and if the issue is ignored, it can lead to more extensive engine damage and a much more expensive repair.

This article breaks down what the camshaft does, common signs of failure, why proper installation matters, and what to keep in mind when replacing a 3406E camshaft. If you are already looking for replacement parts, you can start by reviewing our Caterpillar 3406E Camshaft here.

Posted on June 23, 2025April 30, 2026 by David Ley

Cummins ISL G Cylinder Head Failures: Why Valve Seats Drop and How to Prevent It

The Cummins ISL G natural gas engine is built for a different type of combustion.

And that difference is exactly why the cylinder head fails the way it does.

Unlike diesel engines, ISL G failures are not typically caused by pressure.

They are caused by heat, material fatigue, and valve seat wear.

Posted on June 14, 2025April 30, 2026 by David Ley

Caterpillar C10 and C12 Cylinder Head Failure: Cracking, Valve Seat Wear, and When Replacement Is Required

The cylinder head on a Caterpillar C10 or C12 isn’t just a casting – it’s where combustion, airflow, and cooling all come together.

And when it fails, it usually doesn’t fail quietly.

Cracked heads, worn valve seats, and injector cup issues are some of the most common – and most expensive – problems we see on these engines. If you’re already chasing coolant loss, misfires, or compression issues, there’s a good chance the cylinder head is involved.

Posted on May 6, 2025April 30, 2026 by David Ley

Diesel Engine Failure Diagnosis: Compression Issues

There are many possible causes of engine failure. You can see our earlier post on diagnosing engine failures, too.

Posted on April 13, 2025April 30, 2026 by David Ley

Cummins ISX Crankshaft Failure: Signs, Causes, and What to Do Before It Costs You an Engine

When a Cummins ISX starts running rough, vibrating, or misfiring, most people don’t immediately think about the crankshaft.

That’s the problem.

Because by the time the crankshaft shows obvious symptoms, the damage is usually already happening inside the engine – and it doesn’t take long before it turns into a full rebuild.

If you’re dealing with vibration, low oil pressure, or unusual engine noise, this is one issue you don’t want to ignore.

Posted on February 7, 2025April 30, 2026 by David Ley

Diesel Cylinder Head Cracking: 4 Causes, Symptoms & Prevention

Diesel cylinder head cracking is one of the most serious issues an engine can face – and one of the most expensive if it’s not caught early.

What makes it worse is that it often starts small.

A minor overheating event, a stress point in the casting, or an installation issue can eventually turn into coolant loss, compression problems, and complete engine failure.

Understanding what causes cylinder head cracking – and what to look for – can help prevent repeat failures and unnecessary downtime.

Posted on February 5, 2025April 30, 2026 by David Ley

Caterpillar C15, C15 ACERT, and 3406E Cylinder Head: Failure Symptoms, Causes, and When to Replace

The cylinder head on a Caterpillar C15, C15 ACERT, or 3406E is one of the most critical components in the engine.

It controls:

Combustion Sealing
Airflow into the Cylinders
Exhaust Flow out of the Engine
Fuel Injector Operation

When the cylinder head starts to fail, it doesn’t stay contained. It affects the entire engine.

Posted on January 1, 2025April 30, 2026 by David Ley

Caterpillar C15 Head Gasket Failure: Root Causes, Symptoms, And Proper Repair Process

A failed head gasket on a Caterpillar C15 isn’t just a sealing issue – it’s usually the result of improper clamping force, liner height variation, or thermal stress inside the engine.

Replacing the gasket without addressing the underlying cause often leads to repeat failure.

Understanding why the gasket failed is critical before installing a new cylinder head gasket set.