4 Common Cummins ISM Problems (Troubleshooting)

cummins ism problems
cummins ism problems

An RV is your home away from home. However, even if your RV has all the facilities, if it doesn’t have the right engine, it won’t be a reliable companion for the road. After all, what good is an RV if it breaks down again and again when you are traveling.

The engine is what powers your vehicle, which is why it is the most important part in an RV . The performance of your motorhome, as well as its mileage, depends on the engine.

Additionally, having a good engine will ensure that you do not have to worry about how much weight is being put on your vehicle. However, in order to keep your engine working in perfect condition, it must be taken care of properly. Regular maintenance of your engine is essential to keep it in top condition.

Cummins ISM Problems

When it comes to some of the most popular engines that you can purchase, the Cummins ISM is one of the best choices. Cummins ISM was manufactured specifically for heavy duty vehicles, which is why it is ideal for RVs that have to haul a lot of weight. A Cummins ISM engine comes with a Variable Geometry Turbocharger which means less lag when moving a lot of weight.

However, even the perfect piece of machinery can break down sometime. So, although the Cummins ISM is a great engine for RVs, there are some problems with this model as well. However, if you know what the common problems are and how you can fix them yourself, you won’t have anything to worry about.

Cummins ISM Problems

Before you begin your journey on your RV, you should familiarize yourself with the common Cummins ISM problems. When you know these problems, you can quickly recognize them and fix them instead of feeling helpless in the middle of nowhere.

1. Engine Making Noise

Engine Making Noise

One of the most common issues that people report is that their engine starts to make weird noises. Usually, these sound like someone is knocking on the bonnet and can be heard when you drive above a certain speed limit.

If you are hearing these sounds coming from your engine then there is most likely an issue with the oil you are using. If you are someone who keeps your vehicle maintained then you should already know how this can be fixed.

However, for people who are unaware, the engine oil in your vehicle has to be replaced after a certain mileage. If you have a regular vehicle that you drive occasionally, you won’t need to change the oil frequently.

But considering you are using the ISM engine, you will most likely have a heavy-duty vehicle. Having a motorhome usually means that you will be driving around a lot for your trips.

Considering this, the engine oil in your vehicle can start to thicken up and get dirty after a certain mileage limit has been reached. Sometimes, the oil may start to thicken up even before the limit has reached due to the condition of the road. This is why you should make a habit of checking the condition of your oil while you are on your trip. Fixing this problem is quite simple as all you have to do is replace the oil.

However, you should keep in mind that this has to be done as soon as possible. Driving around your vehicle in this condition will most likely damage it and can even destroy the engine. Additionally, the quality of engine oil that you select is also essential as this directly affects the life of your engine.

Although you can choose any high-quality engine oil, it is better to go for the one manufactured for the engines of RVs. You can also check the website of the manufacturer of Cummins ISM to see if there is an engine oil they recommend for their machines.

If you know how to change the oil, you can do it yourself at home or while you are on the road. But if you have never changed engine oil before, it is better to go to a workshop instead of trying to wing it.

2. Dropped Valve

Dropped Valve

Another issue that can be found on the Cummins ISM lineup is dropped valves. A lot of drivers are not familiar with the term dropped valve and therefore don’t know how to fix this problem.

The dropped valves refer to the valves in your engine getting damaged. While there are numerous reasons why the valves in your vehicle can get damaged, here are some things that you can note down as the most likely causes.

More often than not, the valves get damaged because of human error. It could be something that the driver did or the mechanic. But if you know what the causes are, you can easily avoid them. For instance, if you drive too fast, it can damage the valves of your engine. So, in order to keep the valves from getting damaged, you should drive within the speed limit for RVs.

Backfiring and adjusting the valves in the wrong position are some of the other causes that can damage the valves. The valves can also get damaged if the rotators in your vehicle have gotten weak.

Whatever the case might be, if the valves in your engine have gotten damaged then the only way to fix your issue is by replacing them. It is recommended that you take your vehicle to a workshop to get your engine checked.

This is because checking how many valves have been damaged is only possible by inspecting the engine thoroughly . A mechanic can safely check the engine to find out how many valves have gotten damaged and then replace them for you.

3. Engine Not Working

Engine Not Working

Sometimes, the engine can stop working altogether. Figuring out the cause behind that can take some time as there are a number of things to check. However,  some of the common reasons why your engine can stop working are issues with the camshaft, crankshaft, or pistons.

Trying to identify which of these is causing the issue can be quite difficult if you have no experience of working with engines. If you are someone who understands how these parts work then you should be able to pin down the exact cause easily.

However, most users are not familiar with this which is why they can contact Cummins directly. The company has a warranty service that you can claim if your engine’s problem falls under it. However, even if it is not, the company should still be able to help you with your issue.

4. Low Oil Pressure

Engine Not Working

A good engine oil isn’t enough to keep your vehicle running smoothly, adequate oil pressure is also quite important. If the oil pressure is low, the oil will not flow freely inside the engine, causing friction. Seals can also break inside the engine due to low oil pressure.

Most people think that low oil pressure is caused by low oil levels, but that’s not always the case. If the viscosity of the oil is too high or too low, it could also affect the oil pressure inside the engine. If the oil pump fails, that can also reduce the oil pressure.

If you don’t clean your oil filter regularly, it would get clogged, which in turn will reduce the oil pressure. So, the low oil pressure can be caused by a number of issues, which is why it is better to take your vehicle to the workshop and let professionals inspect it. Once they figure out the issue, they will recommend the best fix to you.

A Cummins ISM engine can keep your motorhome running smoothly on long journeys. But it is important to take care of this important piece of machinery. Regular maintenance can prolong the life of your Cummins ISM engine and help you avoid running into common problems. But if you do run into a problem, the above mentioned solutions can help you get out of them.

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