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Solve ethanol issues before they arise

Written by Charleen

Prevent Ethanol Issues Now

The fuel some love to hate isn’t the problem – letting gasoline sit too long is the real problem.

Len Groom | TECHNICAL PRODUCT MANAGER

How did an alternative fuel made mostly from corn grown in the Midwest become a political lightning rod?

Whatever the reason, ethanol is always a controversial topic. Some love it, citing its ability to reduce our dependence on foreign oil while supporting American jobs. Some hate it, saying it reduces fuel economy and wastes farmland that could be used to grow food.

I’ll leave that debate to someone else. Instead, I want to talk about the effect ethanol can have on fuel-system components, especially in powersports and lawn & garden equipment – and what you can do to avoid those problems.

What is ethanol?

But first, some background info. Ethanol is an alcohol fuel derived from plant materials, such as corn, barley or wheat. It’s mixed with gasoline at different ratios to produce the fuel you buy at the pump. Most of us are familiar with E10, which is gasoline that contains up to 10 percent ethanol. Today, E15 is becoming more common. And owners of flex-fuel vehicles designed to run on increased concentrations of ethanol can opt for E85.

The upside of ethanol

Years ago, lead was added to gasoline to, among other things, boost octane rating and help prevent engine knock. It turned out lead poisoned catalytic converters and harmed the environment, so it was replaced by methyl tert-butyl ether (MTBE). However, MTBE was shown to damage the environment if leaked or spilled. Today, ethanol has replaced MTBE as a more environmentally friendly means of boosting octane.

Fuel-system problems

That brings us to a major knock on ethanol – it’s propensity to degrade rubber and plastic fuel hoses and carburetor components. Ethanol can cause gaskets and fuel lines to harden, crack and then leak. It can also cause aluminum and brass fuel-system components to corrode and develop a white, flaky residue that clogs fuel passages. Some marina personnel I’ve talked to say up to 65 percent of their repair orders are attributed to fuel-system problems.

PHASE SEPARATION

Ethanol isn’t to blame

While ethanol has become a popular scapegoat for mechanics, especially in the marine industry, it isn’t the enemy – time is the enemy. Why do ethanolrelated problems affect powersports and lawn & garden equipment more than your car or truck? Because your boat or lawnmower can sit idle for weeks or even months. During that time, the fuel can absorb moisture since ethanol has an affinity for water. That’s why ethanolrelated problems are so common in marine applications. Water can break the molecular bond between gasoline and ethanol, causing the water/ethanol mixture to separate from the gasoline and fall to the bottom of the tank. This is known as phase separation, and you can see an example of it in the image above.

Phase separation causes a couple problems. The engine can draw the ethanol/ water mixture into the carburetor or injectors, leading to a lean-burn situation that can increase heat and damage the engine. In addition, the gasoline left behind no longer offers adequate resistance to engine knock since the ethanol that provides the increased octane the engine needs has separated from the gasoline. Burning low-octane gas can cause damage due to engine knock, especially in two-stroke engines. Finally, if your boat, lawnmower or other piece of equipment sits unused, the water/ethanol mixture can slowly corrode aluminum and brass fuel-system components, not to mention rubber and plastic fuel lines and gaskets. Eventually those components fail and require replacement.

Driving your car or truck almost every day doesn’t allow enough time for phase separation to occur, which is why we don’t see these issues nearly as often in the passenger car/light-truck market.

Prevention is the best solution

Although some fuel additives on the market claim to reverse the effects of phase separation, there’s no way to reintegrate gasoline and ethanol once they’ve separated. Instead, it’s best to prevent it.

One solution is to use non-oxygenated, ethanol-free gas in your powersports and lawn & garden equipment. It costs a little more, but it eliminates problems associated with ethanol. Another solution is to treat every tank of fuel and container of gas with AMSOIL Quickshot®. It helps keep water molecules dispersed in the fuel to prevent phase separation. It also cleans varnish, gums and insoluble debris while stabilizing fuel during short-term storage.

It’s a great way to avoid ethanol-related problems and keep your equipment protected. There’s nothing controversial about that.

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How do we define “severe service”?

Written by Charleen

How do we define “severe service”?

When pushing our lubricants to their limits, we sometimes find the limits of the test equipment first.

Matt Erickson | TECHNICAL MANAGER – PCLT PRODUCTS AND MECHANICAL R&D

One of my responsibilities here at AMSOIL is to help develop tests in our mechanical lab designed to push lubricants to their limits, both ours and those of our competitors. An effective performance test accelerates lubricant degradation and forces the oil to its breaking point sooner than if tested in the field. This provides more data, faster.

The definition of “severe”

Given the severity of our testing, what happens when the equipment we test fails before our lubricants? Honestly, it causes us to simultaneously rejoice and curse. On one hand, we know our products withstand the toughest conditions we throw at them. On the other, we have to contend with the extra cost and hassle of test equipment that just isn’t built to handle the punishing conditions.

The August 2016 Tech Talk revealed how some two- and four-stroke equipment we’ve tested couldn’t stand up to our test conditions. We’ve run into the same predicament in the passenger car/light-truck market, too.

One recent incident involved the popular General Motors* 3.8L motor. Historically, the GM 3.8L is a rocksolid engine that’s powered millions of cars over the years. It’s a fixture in industry performance testing. One standardized test uses this engine under severe conditions for 100 hours. But our oils soldier through that test like a walk in the park, so we have to triple its length to 300 hours to get useful data. Not an easy task for equipment not designed to handle such extremes.

Well, we recently blew up a GM 3.8L engine. The image shows some of the carnage we found after removing the oil pan. All those bits and pieces used to be a piston.

We ran this test under extreme conditions, as if you were towing continuously at highway speeds uphill for weeks.

Unleaded gasoline

What happened, you ask? First, I’ll ease any concerns you might have: it wasn’t the oil’s fault. We were in uncharted territory, never having an oil last so long in this test before, so we knew we were on borrowed time. In fact, after more than four weeks of testing, the oil hadn’t even reached its breaking point. One of the exhaust valves broke off and fell into the cylinder, where it and the piston were pulverized into the mess you see here. As the piston and valve debris made its way to the oil pan, the crankshaft caught it and blew a hole in the side of the engine block. The severity of our test conditions combined with valve seat recession are to blame.

Years ago, lead was added to gasoline to, among other functions, lubricate the valve seats. Once lead was officially banned from gasoline, in 1996, the fuel no longer provided the same level of valve-seat protection. This lack of protection, combined with the extreme conditions of our test, invited valve recession. When valve seats recede, the valve no longer seats evenly. The result is a loss of heat-transfer that overheats and erodes the valve, as well as an uneven side load that causes the valve to bend slightly on every cycle. This onetwo punch eventually caused the valve to fail. We ran this test under extreme conditions, as if you were towing continuously at highway speeds uphill for weeks. Oil temperatures exceeded 300ºF. The extreme, 1,500ºF exhaust gas temperatures, combined with the constant stress of unevenly eroded valve seats, eventually led to valve failure, snapping a valve in half and destroying the engine.

But our oils soldier through that test like a walk in the park, so we have to triple its length to 300 hours to get useful data. Not an easy task for equipment not designed to handle such extremes.

Suitable for continued use

The good news, however, is the motor oil was still good. Even after hundreds of hours of operation so severe it destroyed the engine, the oil analysis still looked great. It made me smile to see our oil last that long, but it also made me cringe because we were going to have to once again re-test to try to get the oil to break.

This conundrum might present challenges to us engineers, but it amounts to you and your customers receiving the best synthetic lubricants available. We’re happy to keep blowing up engines in our mechanical lab to ensure your engines are protected out in the field.

Given the severe nature of our performance tests, the test equipment sometimes fails before our lubricants.

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