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24 Valve Cummins Problems Explained

If you’re looking for answers to your questions about the 24 valve Cummins engine, you’ve come to the right place. We’ll discuss the causes and possible solutions to the most common problems. Whether it’s Black smoke or a broken Dowel pin, we’ve got you covered. This article also addresses other common issues that may be causing your 24 valve Cummins engine to malfunction. In addition, we’ll cover a number of ways to fix the problem, including replacing the turbocharger.

Dowel pin

If you are having a problem with your 24 valve Cummins engine, then you’ve come to the right place. This article will show you how to replace the dowel pin yourself. This simple procedure can take about 4 hours if done properly. If the dowel pin is completely missing, you may be able to get by with just screwing a screw through the case. Then, make sure you check all bolts holding the case to the engine. Be careful, however, not to tighten or loosen these bolts, as they could cause the same problems as a missing pin.

To make matters worse, the dowel pin may fall into the cam gear and smash into the gear housing. This is bad news for the timing gear, because the pin will then stick in there. The gear housing will then crack where the dowel pin smashed through. Ultimately, you will have an Exxon Valdez in your driveway. And your total repair bill will be $1,000. Don’t let this happen to you.

A killer dowel pin is a serious problem for any Cummins engine. During its initial assembly, this pin was pressed into the engine block to locate the timing gear housing. However, as time passes, it can work its way out of the engine block. It usually contacts the cam gear first, and then slides down into the crank gear. This causes extensive damage to your engine. To fix this problem, make sure to replace the dowel pin.

Another possible source of a Dowel Pin for 24 valve Cummins problem is the front cover gasket. A loose dowel pin can cause all kinds of problems. The pin can fall into the oil pan, hit the cam gear, or get jammed between the timing gears. If not replaced immediately, the engine may self-destruct, resulting in a cracked cam or blown pistons.


There are several different reasons why you should consider upgrading the intercooler in your 24 valve Cummins. Heat is one of the biggest enemies of powertrain longevity, and various condensers are designed to combat this problem. However, the intercooler installed by the factory is often sub-par, and can quickly become plugged up with debris and buildup. To remedy this issue, you should invest in a quality aftermarket intercooler, which has larger end tanks and thicker cores.

Besides the extra weight, the 24v intercooler is about 15% larger than the stock one. You may not be able to find one that will fit a stock 12v support, but a high-quality aftermarket unit will give you a noticeable boost in performance. The intercooler is an important component of any Cummins truck, and can make or break the engine. If your engine is built with the proper parts and is maintained properly, it will give you years of trouble-free service.


Some of the most common signs of a failed 24 valve Cummins turbocharger are a decreased acceleration speed and a whistling noise. In most cases, a problem with the turbo can be resolved through regular maintenance and repair. A bad turbo will tend to burn through engine oil more rapidly and can lead to blockages, leaks and deposits. Grey or blue smoke is also a common symptom, and is magnified when the turbo is in use.

While it may not be a fatal flaw, a failing VP44 fuel injector will make the situation even worse. To remedy this problem, install a new lift pump. The FASS Direct Replacement Pump is the easiest and most affordable option, but you should still purchase additional filtration to avoid any potential problems. If your pump is causing you trouble, make sure it is backed by a warranty.

Another common problem is a failing oil seal. When the seal breaks, the engine can clog up, which can result in high RPMs. To resolve the problem, remove the induction system and post-turbo charge pipes. This is an easy repair, but it should be performed by a trained mechanic. If you do not know the exact cause of your problem, contact a technician. Alternatively, the problem could be a faulty turbocharger.

If you find that your 24 valve Cummins turbocharger is not generating the expected power, you should investigate whether you have a clogged EGR. If so, it will cause the turbo to stall or bog down. If the EGR valve is blocked, it may also cause the car to go into limp mode. Depending on the severity of your problem, you can either replace or repair the turbo.

Black smoke

If you have noticed black smoke coming from your 24 valve Cummins, it might be time to change your engine oil. Changing the oil can have a dramatic impact on the engine’s performance. But the wrong oil can also lead to other problems. There are a number of ways to reduce black smoke from your engine. Here are some simple tips. If you’re unsure of what’s causing your black smoke, you can use the cylinder-by-cylinder oil cut-off method.

If you notice black exhaust smoke coming from your engine, it’s likely that you’ve got a dirty air filter or intake manifold. Dirty HEUI injectors can be a major cause of black smoke. Clean the air filter and lubricate it with oil. Adding a Stiction Eliminator to your engine can solve your problem by restoring your compression. Regardless of the cause, removing and cleaning the filter is an excellent way to eliminate black smoke from your 24 valve Cummins.

The reason that diesel fuel burns more efficiently when it’s mixed with cold air is important. Cold air is more dense than hot air, and so the fuel burns more efficiently. Black smoke results from diesel fuel that hasn’t been properly burned. This fuel is causing your engine to produce black smoke. When you replace your engine oil, you’ll be sure to notice a significant difference in fuel mileage.

Diesel fuel injector failure

A failed diesel fuel injector can be a cause of dirty emissions. The spool valve in your engine can become clogged with debris and deposits. If your spool valve sticks, then the fuel will not burn evenly or efficiently. Dirty emissions and poor mileage are other symptoms of faulty injectors. The repair process usually involves replacing the spool valve and cylinders.

A cracked diesel fuel injector can be visually inspected by removing the valve cover and examining the body of the pump. If you observe cracks on the injector body, you’ll notice a whisp of smoke. This is caused by atomization of fuel coming from the crack. Don’t confuse this with blowby. External cracks in the injector can produce a hint of diesel fuel.

Another problem that can result from a failing diesel fuel injector is low fuel pressure. Ensure that the fuel tank is adequately full, that the fuel pump is delivering fuel, and that the breather is clear of debris. Fuel quality is crucial for Cummins diesel engines because of the internal components. A poor-quality fuel will damage the injectors and cause the engine to run rough. This is another cause of a failed diesel fuel injector in a 24 valve Cummins.

If you notice these symptoms in your truck, you should schedule a visit to a diesel mechanic to have it checked. Often times, a faulty injector can be the culprit for an engine problem. Diesel fuel injectors have a life expectancy of approximately 100,000 miles. You should visit a shop that specializes in fuel injectors. Whether or not you need a repair, make sure you record and repair active DTCs in the diagnostic process.