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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.

How Engine Sludge Forms. And How To Prevent It.

How Engine Sludge Forms. And How To Prevent It.

It’s ugly. It’s sludge.

Sludge.

It’s a disgusting phenomenon. Even the word sounds gross, like the thing it’s describing. The word for this is onomatopoeia, a strange word that many of us learned in high school English class. Splash. Grunt. Whoosh. Swish. Hiss. Frumpy. You know what I’m talking about.

What is sludge?

Sludge is a black gelatinous goo that renders equipment inoperable if not dealt with. And long before the engine’s demise, sludge can foul its sensors and interfere with performance. Some mechanics call it the “black death.”

How does motor oil, which is fluid, become a semi-solid paste or gel inside an engine?

How engine sludge forms

Essentially the formation of engine sludge is the result of a series of chemical reactions. The lubricant itself degrades as it is exposed to oxygen and elevated temperatures. The higher the temperature, the more rapid the rate of degradation. The by-products of this reaction form highly reactive compounds that further degrade the lubricant. Their by-products then react with other contaminants, forming organic acids and high-molecular-weight polymeric products. These products further react, forming the insoluble product known more commonly as sludge. What begins as a thin film of lacquer or varnish deposits on hot or cold metal surfaces eventually bakes into an expensive mess.

Synthetic base oils help prevent sludge

Fortunately, sludge and varnish deposits are something we oil manufacturers have a measure of control over. Using thermally stable base oils reduces the rate of initial degradation (oxidation). A good example of this is the use of common synthetic base oils such as API Group III, PAOs and Esters. Anti-oxidant additives help reduce the rate of degradation as well. One of the most widely used is zinc dithiophosphate. Not only is it an excellent oxidation inhibitor, it is an outstanding anti-wear additive as well.

So do high-quality additives

We can further address many of the issues occurring after the initial oxidation stage. Additive chemistry such as detergents and dispersants are commonly part of motor oil formulation. They help promote the suspension of contaminants within the oil and keep them from agglomerating. Detergents, which are also alkaline in nature, assist in neutralizing acids that are generated in the sludge-building process. Anti-oxidant, dispersant and detergent additives are consumed during use. To achieve maximum life expectancy, use an oil with high concentrations of these additives.

Severe service invites sludge

Good lubricants minimize sludge and varnish issues. How the equipment is used also has a bearing on the likelihood of sludge or varnish issues.

Stop-and-go driving, frequent/long-term idling and operation in excessively hot or cold weather can all increase the likelihood of sludge and varnish, especially if using more volatile conventional oils.

Interestingly, most auto manufactures note in their owner’s manual that operation under any of the above conditions is considered severe service and requires more frequent oil changes. From a mechanical standpoint, things like adding too much oil to the oil sump, antifreeze contamination, excessive soot loading, excessive oil foaming, poor engine combustion efficiency, excessive blow-by and emission-control-system issues can all lead to the formation of sludge and varnish.

By practicing good maintenance and using properly formulated, premium synthetic lubricants, like AMSOIL synthetic motor oil, your vehicle won’t succumb to the “black death.”

LOOK UP MY VEHICE

 

All ADVANCED AMSOIL products are available NOW in Sioux Falls at your full time AMSOIL store: The Synthetic Warehouse at 4610 W. 12th St. Sioux Falls, SD 57107

Just 1 block west of I29! 605-274-2580

Outboard Synthetic 2-Stroke Oil Keeps 1974 Evinrude Running Str

Outboard Synthetic 2-Stroke Oil Keeps 1974 Evinrude Running Str

So many variables determine the life expectancy of an outboard motor that it’s hard to predict with any accuracy how long an outboard motor will run.

But almost anyone would agree that a 1974 Evinrude that is still performing well in 2017 is unusual. If you’re the guy who got it for free, you’re thrilled.

Dealer Mark Neibuhr of Sequim, Wash. has a 1974 Evinrude Silver Starflite 135 hp outboard that he still uses. “I acquired this boat around ‘93 or ‘94, (totally stripped and gutted) and was given the outboard, which needed rebuilding,” Neibuhr said.

It was 2001 when he had the boat seaworthy and the Evinrude rebuilt, he said.

He used the boat in Louisiana before he installed AMSOIL products, Neibuhr said. He had installed the AMSOIL 100:1 oil when he was in Wisconsin, where the boat was used almost exclusively for water skiing in Lake Nebagamon, a small lake in the northern part of the state. Since 2012, he’s used the boat for salmon fishing and crabbing in the salt water of Washington’s Puget sound.

“After many years and hundreds of hours of use in Louisiana and Wisconsin, I moved west to Washington in 2012, where I continue using the boat in the salt water,” Neibuhr said. “It’s still going very strong, like-new compression readings and super smooth running and plenty of power still.”

Sometime in 2006 or 2007, Niebuhr started using AMSOIL Outboard Synthetic 2-Stroke Oil. “I immediately noticed a big reduction in smoke, especially at idle speeds …,” he said.

“The engine has never had any problems whatsoever while running AMSOIL 100:1 oil,” Neibuhr said. “I recently had to open up the powerhead due to a water problem. Upon disassembly, I was amazed at the internal condition of the bearings, cylinder liners, piston and rings, and the overall cleanliness of the internal parts. Most impressive was the complete absence of carbon deposits on the piston tops and ring grooves. I was amazed that after almost 10 years of using AMSOIL the engine looked as good as it did when I rebuilt it in 2001.”

Recently, he decided the boat and engine were overdue for painting and restoration.

“I did considerable research into the original colors and marking of the engine as it was in 1974, and the picture is as close as I could get,” Neibuhr said. “The only difference was a small decal that had ‘Silver Starflite’ affixed to the mid section of the outboard. So I improvised and thought the people at AMSOIL would appreciate my ‘creativity.’”

Why are We Tearing Apart this Indian Scout?

Why are We Tearing Apart this Indian Scout?

(Plus, Check Out this New Product now in Sioux Falls)

Motorcycles occupy a prominent place in our national lore. The V-twin engine, one can argue, belongs in our menagerie of quintessentially “American” items, right next to the bald eagle, the Liberty Bell and Abe Lincoln’s stovepipe hat.

It’s easy to see why. Motorcycles stand for freedom, rebellion, power. For many Americans (like Guinness World Record holder Danell Lynn), a motorcycle is their weapon of choice to fight the specter of an unlived, ordinary life.

One of the best…

Most opt for a Harley-Davidson, whose engines have provided the soundtrack of the American summer for decades. It’s impossible to drive through just about any paved corner of America and not hear the rumble of a Harley. The brand is so firmly entrenched in our psyche that, for many, “Harley” has become the generic term for “motorcycle,” the way “Coke” stands for any soft drink in the South.

Not bad for a company founded in a little shed in Milwaukee, Wis., in 1903.

…but not the first

But for all Harley’s fame, the company can’t lay claim to being the first American motorcycle company. That distinction goes to Indian, founded just two years earlier, in 1901. Throughout the 1910s, Indian was the largest motorcycle manufacturer in the world. The Indian Scout and Chief gained huge popularity throughout the early 20th Century.

But financial trouble eventually beset the company, and Indian ceased production in 1953. One of America’s definitive brands shuttered its doors.

Flash forward to 2011, when Polaris Industries, better known around here for making snowmobiles, bought the brand and injected into it new life…and money. The Chief is back. So is the Scout, which was unveiled in Sturgis in 2014. Motorcycle.com named the Scout its 2015 Motorcycle of the Year.

Today, with sales of V-twins stagnant industry-wide, the Scout has bucked the trend, thanks to its classic styling and lightweight chassis powered by a 100-hp V-twin.

Let the testing begin

This preamble isn’t meant as a commercial for Indian. It’s meant to add context to this Indian Scout that rolled into our mechanical lab earlier this year.


While one look entices most people to jump aboard and hit the streets, it beckons us to drive right into our dyno cell for a few rounds of testing. In fact, this 2017 Scout is replacing our 2012 Harley-Davidson Street Bob, which has accumulated 207,111 miles over the past few years in all kinds of engine testing.

Why the Indian? For starters, we simply like testing things around here. Our mechanical lab is a who’s who in the world of engine and equipment manufacturers. Adding Indian components to our collection of Harley, GM, Stihl, Honda and other parts seemed to fit the bill.

More importantly, we just introduced new AMSOIL 15W-60 Synthetic V-Twin Motorcycle Oil, and it’s recommended for the Indian Scout (along with Victory motorcycles). We already know the formulation works great in the Scout, but we’re never satisfied with “good enough” around here. This bike gives us our own “proving grounds” in which to test, tweak and re-test our formulations. So, in the months ahead, the Scout’s 1133-cc V-twin will be rumbling away in our mechanical lab under the watchful eyes of our technicians.

Once the tests end, the real fun begins –tearing down the engine and examining the pistons, rings, cylinders and other parts. One of my tasks here at AMSOIL is to assist in documenting some of our testing, so I plan to get awfully familiar with the guts of this Scout in the days ahead.

Hopefully we’ll have some interesting results to share soon, so stay tuned.

Until then, get out and ride.

Upgraded Protection for Indian Scout, Victory Motorcycles

 

New AMSOIL 15W-60 Synthetic V-Twin Motorcycle Oil expands the AMSOIL V-twin motorcycle oil product line. It is recommended for the popular Indian* Scout* and all Victory* motorcycles.

Fights heat and wear

Like the rest of the AMSOIL V-twin line, 15W-60 Synthetic V-Twin Motorcycle Oil is designed to resist extreme heat and deliver excellent wear protection. Summer riding can cause engine temperatures to skyrocket, especially in slow-moving rally or parade traffic. AMSOIL 15W-60 Synthetic V-Twin Motorcycle Oil’s outstanding heat resistance helps bikers ride with confidence in the most extreme conditions.

Why is extreme heat so bad for motorcycles?

High heat causes the pistons to expand, potentially leading to catastrophic scuffing and cylinder wear. It also hastens oil breakdown – the rate of oxidation doubles for every 18°F increase in temperature. Oil that has oxidized leads to performance-robbing deposits.

In V-twins, especially air-cooled models, the oil plays a vital role in carrying away heat and dissipating it into the atmosphere via the oil pan or oil cooler. AMSOIL Synthetic V-Twin Motorcycle Oil withstands intense heat, helping your bike last longer and run better.

Helps ease shifting

Riders also like to use an oil that helps deliver smooth shifts. Here again, AMSOIL 15W-60 Synthetic V-Twin Motorcycle Oil delivers. Its wet-clutch-compatible formulation contains no friction modifiers and promotes smooth shifts, helping riders avoid killing the engine.

Find AMSOIL Products for my Motorcycle

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.

Why are There Different Two-Stroke Oil Mix Ratios for Chainsaw Oil

Why are There Different Two-Stroke Oil Mix Ratios for Chainsaw Oil

Swamp mix.

That’s what you call a concoction of two-stroke oil and gas that’s been slopped together with no measuring tools and no regard for engine protection. Your chainsaw or string trimmer could be running on a 50:1 mix. Could be 72:1. Could be 147:1. There’s no telling.

I often made swamp mix back in the day. Like other adherents to the dark art of mixing foul-smelling liquids in a dimly lit shed, I did it for a couple reasons: 1) I didn’t have clearly marked measuring containers at the ready, and 2) even if I had, I wouldn’t have felt like playing chemist with my chainsaw when I’d rather be cutting brush.

I never blew up a saw doing this. But, then again, I’m not a professional logger, so I didn’t cut often.

Some people don’t like mixing two-stroke fuel/oil because it’s a mess. Some hate it because math makes their brain hurt.

What is a two-stroke mix ratio?

The math isn’t that tough to understand. Say your chainsaw manufacturer recommends a 50:1 fuel/oil mix. This simply means you need 50 parts of gas to one part two-stroke oil. Two-stroke engines derive lubrication from the oil mixed directly into the gasoline, unlike your car engine, which lubricates itself with oil housed in an oil sump and circulated by an oil pump.

Complicating things, some equipment manufacturers recommend different mix ratios. While most modern trimmers, chainsaws, leaf blowers and the like call for 50:1, some older equipment recommends 32:1. If you have multiple pieces of equipment with different mix ratios, you have to mix and store multiple cans of fuel. That’s not only a hassle, it’s a situation begging for problems when you accidentally dump 50:1 in your saw that takes 32:1.

This scenario likely isn’t a problem for landscapers, loggers and other professionals who replace their equipment often due to heavy use. But plenty of homeowners still use older equipment that calls for a richer fuel mixture.

Life would be much easier if every manufacturer recommended the same mix ratio, right?

They don’t. But we do.

AMSOIL SABER Professional Synthetic 2-Stroke Oil is tested and proven at any mix ratio up to 100:1. That means you can mix one can of fuel and use it in all your two-stroke equipment. Done. Problem solved. If you want to use 50:1, use that. Or 80:1. For best value, use 100:1. You could mix at 71:1 if you want. It’s up to you.

And, to eliminate the hassles of mixing fuel, we offer bottle sizes matched to certain sizes of gas cans. For example, to mix AMSOIL SABER Professional at 50:1 in a 2.5-gallon gas can, just use an entire 6.4-oz. bottle. Use half the bottle for a 100:1 mix ratio.

That’s the ratio I now use in my chainsaw. As the piston images show, SABER Professional mixed at 100:1 outperforms other two-stroke oils at 50:1, fighting power-robbing deposits and maintaining operability.

AMSOIL SABER Professional mixed at 100:1 delivers better protection against power-robbing deposits than other oils mixed at 50:1.

With SABER Professional you spend less on oil, get better protection and eliminate hassle when mixing fuel. And you never have to make swamp mix again.