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Is an Engine Flush Good or Bad?

Should you be concerned using Engine Flush?

To flush or not to flush. (One of our best sellers here in Sioux Falls)

It’s a question whose answer is obvious in the bathroom, but vigorously debated in the garage.

Let’s get right to the point. Is an engine flush good or bad?

Spend a few minutes perusing online forums and you’ll find a range of answers to this question, often involving a 1980s Trans-Am, Camaro or other car that someone thrashed on for years, parked in a pasture for a decade and now wants to revive with an engine flush.

Here’s what we’ll cover:

  • What is an engine flush?
  • How deposits and sludge form
  • Can engine sludge be removed?
  • Is an engine flush necessary?
  • Engine flush as part of maintenance
  • 5 benefits of an engine flush
  • Engine flush products
  • Watch: How to do an engine flush (video)

What is an engine flush?

An engine flush is an aftermarket chemical additive designed to clean accumulated deposits, sludge and other gunk from your engine. You pour it into your engine’s oil-filler port and idle the engine for about 10-15 minutes. It mixes with the oil and circulates through the engine, helping dissolve sludge and clean deposits. Then, you drain the oil (along with much of the gunk, in theory), change the oil filter, add fresh oil and return to the business of driving.

How deposits and sludge form inside an engine

If it did its job, your engine’s performance will return to the heady days of its youth, when it delivered maximum power and efficiency. Over time, however, harmful deposits and sludge may have accumulated, causing power and performance loss.

The tiny openings in the oil pickup tube screen can easily plug with sludge, starving the engine of oil.

Deposits and sludge can form for several reasons, including…

  • Frequent short trips that don’t allow the oil to fully warm up and evaporate moisture
  • Ingestion of air-borne dirt
  • Fuel dilution
  • High heat breaking down the oil

As it settles, sludge can clog narrow oil passages or the screen on the oil pickup tube, restricting oil flow to vital parts, especially the upper valve train. Deposits can cause the rings to stick, reducing engine compression and horsepower.

Can engine sludge be removed?

Yes. The proper detergents in the correct concentration can dissolve engine sludge, deposits and varnish. Ideally, sludge won’t form at all; however, sometimes mechanical issues arise, such as a leaking head gasket, and the formation of sludge occurs. If sludge does form, the oil’s detergents help dissolve and disperse sludge to clean the engine.

This is more challenging than it sounds. For starters, the oil must perform several functions, not just help prevent engine sludge. For that reason, oils contain a limited concentration of detergents (compared to an engine flush product) to ensure room in the formulation for other additives that protect against wear, fight oxidation, combat rust and more.

An engine flush product, on the other hand, is designed solely to clean. AMSOIL Engine and Transmission Flush, for example, contains nothing but potent detergents, making it a more effective cleaner than motor oil. Plus, it cleans at the molecular level, ensuring deposits are dissolved and properly exit the engine with the oil when it’s drained. This is important since some motorists fear that an engine flush will free large chunks and cause an avalanche of debris to clog passages inside the engine. AMSOIL Engine and Transmission Flush guards against this scenario.

Is an engine flush necessary?

A good engine flush can help loosen deposits and dissolve sludge, returning your engine to like-new condition. However, in old engines with high miles, sludge may be the only barrier keeping oil from seeping through worn or cracked seals. Removing the sludge exposes the seals for what they really are – junk. Soon, your engine begins leaking oil, and you’re mind instantly associates the engine flush product with an oil leak.

In reality, the seals were already bad; the flush simply revealed their true condition.

If you suspect your vehicle falls into this camp, leave well enough alone and skip the engine flush. It’s probably not worth trying to revive an engine in such poor condition without first fixing the bad seals or other defects.

In effect, you’re choosing your problem: either sludge and deposits robbing performance or, if you clean the engine, the seals showing their true condition.

An engine flush is part of a good maintenance regimen

But that’s not to say an engine flush is never a good idea. In fact, it’s often the first step in helping restore a neglected vehicle to top-notch performance. And, often when you buy a used vehicle, that’s what you’re getting – a vehicle whose owner found antiquing on Saturday afternoon more enjoyable than changing oil or dropping the transmission pan. Consequently, your “pre-owned” ride, while not complete junk, may boast a sketchy maintenance record.

In these cases, a potent, detergent-based flush can help prepare the engine for new oil, loosening sticky valves or rings and helping remove harmful sludge. While not a required step when switching to AMSOIL synthetic motor oil, we do recommend flushing your engine if you want to give your vehicle a fresh start.

5 benefits of an engine flush

1. Prepares your engine for new oil

An engine flush helps loosen sticky valves or rings and remove harmful sludge and other contaminants. By cleaning the engine prior to installing fresh oil, you ensure the new oil functions as intended and delivers maximum protection. The oil won’t last as long or protect as well if it must contend with sludge and deposits from the previous oil.

By the way, we don’t require use of AMSOIL Engine and Transmission Flush before switching to AMSOIL synthetic motor oil, but we recommend flushing your engine if you want to give it a fresh start.

2. Helps increase fuel efficiency

Contaminants circulating throughout the engine can lead to oil breakdown and increased viscosity – and higher-viscosity oil requires more energy to circulate throughout the engine. Sludge and deposits on engine parts can also increase resistance, which wastes fuel to overcome. Cleaning the engine helps ensure parts move efficiently, maximizing fuel economy.

3. Helps reduce emissions

If deposits in the piston-ring lands cause the rings to stick, oil can migrate into the combustion chamber, where it burns. This not only leads to harmful deposits, it also increases exhaust emissions as the burned oil exits the tailpipe. A good engine flush helps free stuck rings and reduce oil consumption, in turn reducing emissions.

4. Helps reduce heat

Excessive heat is bad for your engine and the oil. Extreme heat reduces engine efficiency while increasing the rate at which the oil oxidizes (chemically breaks down). Sludge and deposits act as insulators that prevent the engine from dissipating heat as designed. Flushing your engine helps ensure it manages heat properly for optimum efficiency and oil life.

5. Convenience

This might not apply to every engine flush, but it applies to AMSOIL Engine and Transmission Flush. It delivers results after just one application. And it only takes 10-15 minutes to use. Plus, you can safely use it in gas or diesel engines and automatic transmissions. While some solvent-based flush products require a cumbersome disposal process, AMSOIL Engine and Transmission Flush uses a detergent-based formulation. As such, you can dispose of it easily with waste oil.

Cylinder head pre-cleanup. Note the sludge around the valve springs and push rod openings.

Post-cleanup with AMSOIL Engine and Transmission Flush, the cylinder head is noticeably cleaner.

Engine Flush Products: I use AMSOIL Engine and Transmission Flush

For the record, I’ve used AMSOIL Engine and Transmission Flush on three different pre-owned vehicles in my time, and it’s worked great. One of them, a 1999 Honda CR-V, accumulated more than 220,000 miles before rust forced me to replace it. Another, an Oldsmobile Intrigue, ran great until a computer problem forced me to trade it off…for the CR-V. The third ran great, but I sold it off after it, too, rusted out.

In sum, flush your engine if you want to give your vehicle a new lease on life. AMSOIL Engine and Transmission Flush, as the name indicates, also works great for cleaning automatic transmissions. Check out this post to determine if a transmission flush or pan drop is better for you. But if you have any reservations about disturbing sludge or deposits that may be holding your old, high-mileage engine together, consider skipping it. It’s up to you.

How to do an engine flush

If you are looking for the best way to flush your engine this weekend, here’s a quick video that will walk you through the process, courtesy of MyJeepStory.

video
play-sharp-fill

How Do I Switch from Conventional to Synthetic Oil?

How Do I Switch from Conventional to Synthetic Oil?

To borrow a famous slogan, just do it.

There is still some confusion about changing to a different type of oil in vehicles, particularly older models that have accumulated many miles. A small group of ill-informed individuals in garages and on blogs still cling to old beliefs that synthetic motor oils cause roller followers to “slip or skid,” or that switching to synthetic motor oil causes issues in older engines, particularly oil leaks.

Facts have since replaced these outdated ideas about synthetics causing engine problems.

The use of synthetic lubricants is growing rapidly because properly formulated synthetics offer benefits well beyond what conventional and synthetic-blend products provide. Many new passenger car and light truck vehicles come factory filled with synthetic lubricants – not just high-performance sports cars.

There are a couple ways to switch to synthetic motor oil for the first time.

• Jump right in and simply change the oil. Take your vehicle to your mechanic or the nearest quick lube and ask for synthetic motor oil. Or, dust off your drain pan and do it yourself. You don’t have to do anything special to your engine first, and the synthetic oil isn’t going to cause problems in your vehicle that weren’t already there.

• Flush the engine first. Though not required, an engine flush more immediately removes sludge and debris accumulated over time. AND neutralizes acids so the new oil’s detergents can be more aggressive to keeping your engine deposit free.

The main difference between flushing your engine and a normal oil change to synthetics is the rate at which the built-up debris is removed from older engines. If you change to AMSOIL synthetic motor oil without flushing, for example, the detergents in the motor oil will clean accumulated deposits from the engine over subsequent oil changes. When you useAMSOIL Engine and Transmission Flush, the cleanup is more immediate and helps ensure the engine is clean and free of any accumulated contaminants.

Wondering if an engine flush is right for your vehicle? Find out here.

However, we recommend using AMSOIL Engine and Transmission Flush if you want to give your engine a fresh start before switching to synthetic motor oil.

Ready to make the switch to synthetic motor oil? Check out our Product Guide for the right oil for your vehicle.

FIND AMSOIL PRODUCTS FOR MY VEHICLE

The 3000 Mile Oil Drain Fails To Address The Real Issue

The 3000 Miles Oil Change Interval Doesn’t Address Oil Quality

When people say to me they change their oil at 3000 so not to take any chances that dirt could be causing damage or the oil could be getting “bad”, I say to them, why not change every 50 miles then?? I’m sure the oil is still good but as you said, why take a chance?

Let’s look at the top reasons for engine failure which relate to the oil.

#1 is lack of lubrication. Nothing to do with dirt but a poor quality non-synthetic even low quality synthetic made from Group III base stocks (There are over 80 different quality levels for a Group III oil thus lower prices – this does not fit the scientific definition of synthetic) can and will leave deposits OR lose viscosity early on both causing lack of lubrication.
#2 – Overheating – Often the damage done after a engine overheats is caused by the heat being too intense for the oil to hold its properties. An AMSOIL product would have prevented this especially in air cooled (V-Twin bikes or marine) and in the new trend of turbocharged engines. The coming LSPI issue will demand the oil be at least a 100% synthetic quality. It’s designed for temperatures beyond these issues.
So changing oil every day will not prevent the above. Any overheating event or the list of reasons which cause a lack of lubrication cannot be addressed by the 3000 mile oil change. Only by the quality of the oil. AMSOIL also adds performance and for the difference in price per quart is less than the cost of a cup of today’s coffee so the solution for protecting your investment is here!! And has been for 45 years.

Quality Oil Filtration is a Must but still only part of the issue

I couldn’t find the study as I was writing this but Federal Mogul published research that “dirt” in oil was actually a minor part of failure while things relating to lubricant quality were. Acids or loss of TBN was a much more severe issue. Corrosion and storage was a far greater contributor to reduction in engine efficiency and ultimately failure.

Mild quality oil filters solve the dirt issue for up to 10,000 miles but you still need an oil which can fight contaminants caused by fuel or advanced wear over the years (such as starting with a used vehicle which you don’t know the history of). AMSOIL addresses the contaminants with their advanced additive packages and are willing to cover that with a guarantee.

How do you know?

Note while that AMSOIL does back their oil for longer intervals, this is clearly stated for engines which are in normal operating condition and have not been modified. For modified engines, neglected ones or those with a good number of miles over 100,000 they do list severe service categories or one can always get our KIT-02 oil analysis kit and go from there.

Just use better oil and find out what you are missing!

AMSOIL use will tilt the scales of a nations fleet replacement statistics. Imagine that. Just from changing brands of oil.

The 3000 mile oil change interval excuse is much like arguing one brand of cigarettes is more healthy than another.
Use AMSOIL and unlock the full potential of your drive train!! Find out what others already know – AMSOIL is all about performance!
Ches Cain – AMSOIL Direct Jobber

Engine Deposits can be Prevented using Superior AMSOIL Lubricants

Help Preserve Your Engine’s Horsepower

performance_oil

Although you may equate engine wear and deposits with sudden, catastrophic engine failure, they are more likely to erode engine power and efficiency over time. Here’s how it works and what you can do about it.

Several factors cause an engine to slowly lose power, but one of the primary reasons includes compression loss due to wear and deposits.

Engine compression = power

For your engine to produce maximum power, the combustion chamber must seal completely during the compression and combustion strokes. Wear and deposits can prevent the valves or piston rings from sealing, allowing pressurized gases to escape the combustion chamber and take potential engine power with them.

To illustrate, imagine using a hydraulic floor jack. Pumping the handle will raise the vehicle as long as the release valve is tightly seated and doesn’t leak. A poorly sealed release valve, however, allows pressure to escape, causing the vehicle to sink to the ground no matter how much you pump the jack handle.

The same principle applies inside your engine. If some of the pressure created during the compression and combustion strokes is lost due to valves and piston rings that don’t seal completely, the engine will create less power.

Wear & deposits reduce compression

Over time, deposits or valve wear can prevent the valves from closing completely, interfering with a good seal. Wear can also interfere with proper valve operation, disrupting optimum fuel/air flow.

Worn or stuck piston rings produce the same effect. The rings are designed to move freely in their grooves and press tightly against the cylinder wall, forming a seal that prevents fuel/air from escaping. Ring wear can interfere with formation of a tight seal, while deposit buildup can cause the rings to stick in their grooves, also preventing a good seal. As a result, some fuel/air escapes the combustion chamber during compression, reducing power. On the combustion stroke, pressurized gases can blow by the rings and travel down the cylinder wall and into the oil sump, taking potential power with them. This is what’s meant when someone says an engine has lost compression.

AMSOIL Signature Series helps prevent the problem

A lot is working against you including the quality of the gasoline available here in Sioux Falls. Everything you can do to prevent deposits goes a long way saving you money in the long term no t to mention engine life. AMSOIL Signature Series Synthetic Motor Oil provides 75 percent more engine protection against horsepower loss and wear than required by a leading industry standard*, extending the life of vital components like pistons and cams. In addition, it prevents piston deposits 93 percent better than required to meet the latest API standard.* Its outstanding performance helps prevent deposits and wear that rob engines of horsepower, helping preserve that like-new feeling you crave when driving. The secrete is in the low volatility of the oil. That can only happen when quality is the main driver of the firm.

deposits_in_engine

*Based on independent testing of AMSOIL Signature Series 5W-30, in ASTM D7320 as required by API SN specification

Ches Cain – AMSOIL Direct Jobber

Your Sioux Falls Power Gain by Oil company. Most AMSOIL customers discovered AMSOIL via word of mouth due to performance only!! Not because our products save fuel or last 3X longer. It’s the real benefit of performance you can feel!! So compare that to other brands and more research will unveil the BIG lie they “don’t” offer to the consumer as advertised. AMSOIL is a family owned and operated business. No greedy stockholders to effect the choosing of additive packages.