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How to Get More Life from a Cummins Diesel Engine

4BT, 6BT Build Cycle Completion 5-2-19

6BT (5.9 L) 210 HP Engine

Diesel technology has come on leaps and bounds in recent years, from ultra-low sulfur diesel to biodiesel, gaining DPF filters to cut down on emissions, and high efficient common rail injection systems to gain maximum miles per gallon. All of these changes are good news if you are taking the required steps to keep your diesel engine running at a high level of performance and efficiency. But of course these components will need care and attention to carry on operating at maximum capacity. This guide will be a good starting point to learn how to care for your engine, if your new to diesel engines, and a good reminder for those of you who are more experienced enthusiasts.

So, the general consensus seems that a Cummins engine’s life expectancy is from 300k-400k miles, but if you follow the correct steps, you could, and should have some sort of control over the life span of your engine, and we don’t think crossing your fingers will really suffice. For those of you approaching these figures, or in fact, anyone wanting to increase the life expectancy of their Cummins, this article will focus on how you can increase the longevity of your engine. First and foremost, if you look after your engine, it will look after you. So, without further ado, here is a brief guide on general maintenance to keep your engine healthy.

The tasks are the usual:
• Regular oil changes
• Fluid changes
• Air filter changes
• Fuel filter changes

With regard to the filters, its probably a good idea to change them when the manufacture recommends. You can find this sort of info on the packaging or the website of the manufacturer.

What to do, and what not to do...

A well-known fact is that an ounce of prevention is preferable over cure, therefore do your preventative maintenance to anticipate wear and tear. Pay special attention to you fuel injector also, replacing a diesel injector that’s at the end of its tether will save you money rather than waiting until it eventually croaks. Another useful tip is to add a bottle of diesel treatment every time you fill your tank, this will prevent the diesel becoming saturated by the impurities floating around your tank which will prove beneficial for your parts.

Do not, empty your engine fluids until they are at a cool temperature. Diesels tend to run a lot hotter than gas engines and doing this while its hot can cause serious injury and more importantly, it can damage your engine. Also, do not ignore your engine if its running hot. Your diesel is running at thrice the compression pressure than a gas engine, which of course takes it toll on the cooling system. So, make sure to keep your water pump in prime condition.

Key Diesel Engine Components to Lookout For...
Your maintenance could be second to none, but even Cummins' engines can succumb to themselves now and then so here a brief checklist of symptoms to look out for:

Throbbing RPM’s: if your RPM’s are pulsating all over your dial, you may have a blockage in your diesel injector.

Blown Head Gasket

Blown Head Gaskets are Common Issues

Gasket leakage:

The extreme pressure your gaskets endure can be pretty wearing. Therefore, if one kicks the bucket, replace them as a set. High-pitch tones coming from your engine: If this applies to you, then there’s a possibility it could be your diesel fuel pump. Different pumps will make different sounds, but this is a good place to start your investigation.

Thick Smoke:

If you end up seeing a trail of thick smoke following you from your rear-view mirror, the color of the smoke can offer some deduction to the problem.

• Black: Faulty diesel injector, pump, or air filter
• Blue: The burning of engine oil
• White: Possible water in your engine, or low compression.

If you spot or recognize any of the above symptoms, it’s probably wise to consult a diesel mechanic. So, that’s general maintenance and warning signs out the way, but what else can you do day to day? This section will focus on small changes you make, that will go a long way.

Holset HX30 TurboTurbochargers:

Turbochargers play a key role in making your diesel run efficiently. So, to get the maximum life and performance from your induction system, there’s a few things to bear in mind.

• You may have heard this before, but ill say it again. ALWAYS, ALWAYS ALLOW YOUR VEHICLE TO IDLE FOR A MINUTE OR TWO UPON START UP. If not for you, do it for your engine, if that’s not enough of a reason, then do it for us, please. If you jump in and start hitting the gas from the get-go, then you are potentially causing some serious damage to your engine. You need to allow for your oil to reach all the necessary areas, and your turbo is only one of these.

• Oil additives are a good idea too, they are brilliant for tubrochargers and oil systems in diesels due to the amount of heat these things produce. The oil additives will help lubricate the system even when running at peak levels it will help even the most less significant components.

Biodiesel, ULSD and Diesel fuel additives:

Diesel Fuel ImageFuel tends to fluctuate between ULSD and biodiesel. These are the two prominent fuels you’ll come across in most truck stops or fuel stations. So, regardless of what is readily available, a diesel fuel additive is always a wise choice. If you want your injectors to maintain a nice even spray pattern and operating a maximum capacity, then take this advice on board.

It is preferable to find a fuel additive that demulsifies water. A large amount of these additives will try and burn the water out via the injection system. The logic behind this is something we struggle with daily. Why would you want to make it harder for your vehicle that comes equipped with a fuel water separator? The fuel water separator obviously takes the water from the diesel, so find an additive that removes water instead, to make that systems life a little easier.

Diesel fuel additives can also be good for fuel gelling. Most winter blends have an assortment of additives already but supplemental quantities are always advisable. During the winter months, nobody really wants to go out to their vehicle and be greeted by a nonstarter. So, for your own peace of mind, use a fuel additive.

Diesel coolant and... more additives:

We mentioned this a few times, but diesel engines run at high temperatures, so...COOLANTS! If you have ever walked into a parts store for coolant and had absolutely no idea what you actually need, we will advise you in the next article on that topic. There are different colors and specs, but which is right for you? For a start, go with the OEM recommended coolant.

Mixing coolants is a terrible idea, this is very bad for your engine. The chemical reactions that could occur can leave your system looking like a smoothie gone wrong. Potentially, this could catalyst a number of new issues and leave you possibly needing a new engine. Water is also a bad idea, if its your last hope then yeah, do it but switch it out as soon as you can. The problem with this is that water will not disperse the heat like an actual coolant. So, if you make a habit of this your engine block could eventually crack and freeze over the colder seasons.

Break-In Procedure and Idling Concerns:

Avoid long journeys during your engines break in period, it takes a little while to break in your engine, you have to drive between 2000 and 3000 miles before its considered fully broken in. You a standard vs. synthetic oil for that break-in period as you want to rings to seat properly. If you don't you'll have cylinder glazing and the engine will always leak oil. A lot of manufacturers recommend driving in stop and start environments and to avoid sustained speeds. It's best to put it under a moderate load and use that engine! Overall, you don't want to idle the engine for hours at a time... that is a good way to ruin a new engine. Also, try to avoid towing during the break-in period. Taking proper care of your vehicle over this period will ensure your truck improves it power and efficiency over time.

We know two sorts of people, the ones that try to keep their tank full at all times, and those who keep their truck going on the lower third of their tank...constantly. We advise that it is wiser to keep your tank full, especially if uses are few and far between. Although, you don’t have to do this all the time, some come equipped with filters and breather vents to prevent the build-up of moisture.

We know I said earlier to idle your engine upon start up, but don’t idle your vehicle for to long. Prolonged idling is obviously bad for our environment, but it will bring your engine to an early demise. The prolonged idling causes insufficient lubrication on the piston wall which could lead to piston and cylinder block scoring. In ye oldie times, diesels were required to run constantly to prevent the fuel from gelling. However, now this is not the case so, if your taking advice from a stubborn old timer who’s telling you to idle your engine, politely ignore his advice.

Save your injectors and use quality fuel. Poor fuel will have a negative impact on your injectors. The injectors are prone to damage and as you may well know, expensive to replace. Keep in mind that you may have to replace all injectors if this happens. The damage to the injectors will be illustrated by the smoke produced by the engine, or how the vehicle behaves. The exhaust fumes could be pumping out black or white smoke, and the vehicle could start chocking.

Again, on the turbochargers, these require special attention. The key here is to let it cool down after your finished driving. Specialists advise that it is best to leave it running in ‘N’ for about 20 seconds – 2 mins after you have stopped your vehicle before you switch the engine off. Also, for your first couple miles, try and drive smoothly and avoid sudden changes in speed.

Laying Rubber can also damage your turbocharger but can also force you into replacing the dual mass flywheel. If you break this, then remember you’ll have to replace your clutch as well.

DPF Filter

Make sure to clean your DPF regularly

CLEAN YOUR PARTICULATE FILTER, the DPF is there to remove the soot from you exhausts. These filters were born to reduce emissions and if you don’t clean them properly, the filter can be damaged by a build-up of ash. The chances of this increase if you are mainly city driving and don’t really get a chance to get to higher speeds to burn off the particulate matter. This is because when your driving at speed, the filter can clean itself out.

Final Advice on Cummins Engine Maintenance

Some final words of advice would be to not ignore small problems. No matter how much money your trying to save for various truck parts, don’t ignore the lingering problems, as they could cost you a fortune if they evolve. This brings us to our next point, don’t skip your inspections. You should ideally be scheduling regular maintenance check-ups with a mechanic or dealership that is knowledgeable with your specific model. For example, if your equipped with the 2004 5.9 L (6BT) Dodge Ram using OEM Cummins Bosch injectors, make sure the person inspecting your vehicle has prior experience with these parts. It’s also a good idea to schedule replacement parts or repairs with the same guy, or girl who carried out your inspection.

Due to the fact we have encouraged a lot of additives for your engine, we feel obliged to offer you a brief explanation. If you compare the properties list for gas and diesel, you will see diesel has more wear properties in need of protection from additives. You may have noticed that there are more diesel focused additives on the market, both with multi-functional additives and the single purpose treatments that fuel suppliers have to use to make sure the diesel they distribute, stays within its legal parameters.

This may be due to the fact that gas is pretty highly refined when compared to diesel which is a heavier substance, therefore more prone to going “off-spec”. Lubricity, cetane rating, cold weather performance and stability are all the key properties that must be protected and assisted by these additives we seem to be forcing down your throats. So, there you have it. The above guide is at least a good starting point when learning how to keep your Cummins Engine healthy, and prepared for a long-lasting life.

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