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World’s Most Powerful Outboard Motors Rely on AMSOIL

World’s Most Powerful Outboard Motors Rely on AMSOIL

Seven Marine, maker of the world’s most powerful outboard motors, has a saying: We move the people who move the world. The Germantown, Wis. company designs, builds and sells outboard motors that produce up to an astonishing 627 hp and power some of the fastest and most impressive watercraft in the world.

All that power places tremendous stress on their sophisticated motors, which is why they turned to AMSOIL synthetic lubricants as their factory- and service-fill lubricants after having previously used Mobil* products. We sat down with Eric Davis, Seven Marine Vice President, to get the story.

AMSOIL Magazine: What makes Seven Marine unlike any other manufacturer of marine motors?

Eric Davis: We build the most powerful outboards available on the market today. We use a completely different technological approach than any other outboard manufacturer by using the small-block supercharged V-8 out of the Cadillac* CTS V and applying that in its normal horizontal configuration under the cowl. And that really makes Seven Marine unique because all other outboard motors are vertically oriented. That means we can use the performance, quality and emissions advancements that are central to automotive engines and apply that to outboard motors for the first time. In addition, we pair the engine to a ZF* marine wet-disc-clutch transmission. We’re the only outboard that uses a transmission. Because of that, our motors don’t shift in the lower unit.

AMSOIL Magazine: What performance advantages does that design provide?

Davis: It allows us to optimize the lower unit with a twin-pinion, race-inspired design that’s smaller in diameter. That benefits us in high-speed-cruise fuel economy and top-speed capability. A twin-pinion also gives you a tremendous amount of durability.

So, when you use a horizontal crankshaft engine, go with a wet-disc-clutch transmission and finish with a twin-pinion lower unit, you really get an outboard that’s built completely different, which is how we’re able to deliver the amount of power and torque to the propeller that sets us apart from everyone else.

AMSOIL Magazine: Your most powerful motor produces 627 hp. On what type of watercraft are people using your outboards?

Davis: The vast majority of our applications are multi-engine, and the trend lately has been more quads than anything [using four engines simultaneously]. We address the market that’s called the ‘super consoles,’ so we’re talking about 40-plus-foot, centerconsole, off-shore boats. Four engines can be done using a boat as short as 43 feet and as long as 61 feet.

AMSOIL Magazine: Who’s buying your outboards?

Davis: By the time you find out what they’ve done or what they do, they’ve touched your life in some way, shape or form. We use as a corporate tag line, ‘The Power to Move Those Who Move the World,’ and that really came from the fact that our customers are exactly those people, whether it’s the northern hemisphere’s largest onion farmer or the family that owns the third-largest grain distributor in the world – all kinds of people like that. They have truly amazing stories.

AMSOIL Magazine: How do they use your outboard motors?

Davis: It varies a lot. In general, they use them for transportation. They’re moving great distances, and what makes the applications unique for Seven Marine is that they’re trying to traverse those distances at high-speed cruise. They use the applications for everything from island-hopping to poker runs to deep-sea fishing. We have customers in the Gulf of Mexico who are running 150 miles to fish the rigs, so they’re cruising three hours at 50 mph to get out there and fish. We have people in Alaska 150 miles from civilization. Generally speaking, they’re covering great distances at pretty good clips.

AMSOIL Magazine: Why did you choose AMSOIL synthetic lubricants for your engines and transmissions?

Davis: When you’re trying to deliver the most luxurious experience for the customer and deliver the most performance at this level of power, you really have to have the best of everything to make sure it works properly. And you have to be confident that you have the best lubricants to ensure you’ve got the ultimate in durability. AMSOIL, on the engine and transmission side, has been the best products we can find. That allows us to be confident that when we do a factory-fill and recommended servicefill with AMSOIL, that you’re going to get that same factory performance day-in and day-out.

AMSOIL Magazine: What did your own test results tell you about AMSOIL products?

Davis: When we started doing oil sampling from dyno testing and looking at the performance of the oil and its degradation, the AMSOIL results were superior than what we were using before [Mobil products]. We’re endeavoring to build the absolute best world-class products we can and innovate in the marine industry, so we prefer to have an oil that we feel is as innovative and technologically advanced as the engines that it’s going into, and that leaves us with AMSOIL

In Sioux Falls review our marine 10W-30 and 10W-40 4-stroke oil for the big blocks, the new Mercury 25W-20 and several 2-stroke oils for injection units both OEM and our famous HP Injector formula and the 45 year old 100:1 outboard pre-mix.

And our best seller – the highly stable and water resistant Marine Gear Lube 75W-90.

How do we define “severe service”?

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.