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Inside the Mercury test center, where nitpicking is encouraged

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Carrying arms called “J Hooks” hold outboards as workers assemble, check and test them at Mercury Marine’s Fond du Lac, Wis., production plant.

Carrying arms called “J Hooks” hold outboards as workers assemble, check and test them at Mercury Marine’s Fond du Lac, Wis., production plant.

FOND DU LAC, Wis. — I was standing in the sound lab at Plant 12 of the Product Development and Engineering testing center at Mercury Marine’s manufacturing headquarters.

About a dozen microphones dotted the room, and a mannequin’s top half — with mics inside its ears — faced one of Mercury’s new 115-hp 4-stroke outboards. The engine sat in the center of the room, with its lower end passing through an opening in the floor into water. A tank that equaled the entire footprint of the room held the water — 30,000 gallons of it at a depth of 4 feet.

A mount (about the size of an extra-large pizza pan) holding 54 microphones and one central camera also pointed toward the engine. A knee-high tripod held this acoustic array, which allows Mercury to locate engine vibration and sound abnormalities. The mannequin records the “sound signature” that engineers use for playback to help them fine-tune the sound of the engine.

The 1,000-square-foot sound room was one of a half-dozen sections of the Mercury plant that I — along with a group of fellow journalists — was able to tour in June as part of a three-day press event. The engine maker’s $17 million expansion was completed this summer. The sound lab has been in use since 1999.

I was fascinated with it. Wedge-shaped protrusions covering the walls and ceiling absorb noise, and the floor reflects sound — just as the air on a bay or lake soaks in sound and the water reflects it, said Jeff Etapa, technical lead of the sound lab and the Noise, Vibration and Harshness dynamics test team.

“We take it to the next level,” he says. “We want the engine to be quiet, but we also want it to sound a particular way. This room allows us to nitpick and really dial in the noise, vibration and harshness characteristics of the engine.”

About 450 Mercury engineers and technicians work here in Fond du Lac. The Wisconsin employee count has risen by 87 percent since 2009 and the company says it had 3,000 employees in 2013.

A sophisticated “sound lab” allows Mercury engineers and technicians to measure, then fine-tune the noise, vibration and harshness characteristics of the engine.

A sophisticated “sound lab” allows Mercury engineers and technicians to measure, then fine-tune the noise, vibration and harshness characteristics of the engine.

Mercury has beefed up its facilities with 38,000 square feet of manufacturing space for die-cast and machining. The closing of the company’s 700,000-square-foot plant in Stillwater, Okla., prompted the expansion. Since 2009, the engine maker — founded in 1939 by Carl Kiekhaefer — has invested more than $500 million in PD&E and expansion and has been steadily hiring. It also has spent $300 million on research and development to support the design and manufacture of new products.

At a press event in nearby Oshkosh, Wis., Mercury introduced a 4.5-liter 250-hp sterndrive gas engine and three outboards — 75-, 90- and 115-hp second-generation 4-strokes.

The tour also included a look at Plant 15 — which includes product testing (performance and durability). We walked through engine assembly areas. The last stop was Plant 17, the high-pressure die-cast area.

I saw up close the test cells for gasoline and diesel sterndrive engines. I watched a Mercury test worker monitor five computer screens filled with tabulations of data from the test subject — the new MerCruiser 250-hp sterndrive — in one of three new testing cells (there are a total of 19 cells). “Some cells are testing outboards only and some sterndrives only and some a combination of both,” says Dave Kahlow, the PD&E lab manager.

“Mike is responsible for developing the base calibrations of our engines,” says Kahlow, referring to the tester at the controls. “He is looking at combustion analysis, ECU data, emissions, all the temperatures, pressures and flows of the engine. If he makes a change in spark or fuel, he has 200-plus items that he has to monitor to see what the effect is on fuel economy, power, torque, emissions, etc.”

Kahlow also pointed out that they can test using different temperatures of water from 4 to 38 degrees C.

The computers sat just outside the cell. The tester kept an eye on the engine by looking through an observation window.

A new product platform may undergo 18 months to two years of this kind of testing, Kahlow says.

For production validation, 15 to 60 engines can be used to test one model, adds Ron Hall, manager of MerCruiser Current Products.
In this area, short-term testing for data collection takes place. Next, we visited the durability testing area. Engines and drives are put through thousands of hours of testing in stainless steel and aluminum tanks.

“This last year we added two tanks, specifically for larger-horsepower engines,” says Doug Czaikowski, systems engineer in the test center. “These tanks have the capability of running 1,000 hp — that could be a combination of two engines, such as [diesel] engines for the Zeus pod drives, but it could be for a racing product, as well.”

Each of the water tanks holds about 30,000 gallons and they are tied to two exhaust-treatment systems, Czaikowski says.

“The engines can be set up to go through automatic cycles, and those cycles can be wide-open throttle for hundreds of hours or it might be what we call a ‘fisherman’s cycle,’ where we run the engine at idle for six or seven hours and then jump right to WOT for two to six hours and then jump back to idle for six or seven hours.”

Eight fuel tanks outside hold everything from diesel to premium gasoline to ethanol fuels to specialty fuels, such as those from third-world countries, Czaikowski says. Technicians control the temperature and humidity of the air feeding the engine in the combustion chamber, as well as the temperature of the water supplied to the engine. The tanks are sealed so the exhaust can be pulled out and fresh air piped in.

The test center’s computer equipment has “really taken our testing to a higher level,” Czaikowski says as he wraps his portion of the tour. “We can get to the root of a problem quickly. We find out which came first, the chicken or the egg.”

Next we visited the assembly building, where engines from 75 hp and higher are put together.

We had to don steel-toed shoes before we entered for a 30-minute tour. Lead quality engineer of outboards Jason King led the way. A fleet of outboard gearcases greeted us first. They are checked for precise dimension parameters before moving through assembly.

Yellow carrying arms, appropriately called “J Hooks,” held outboards as workers assembled, checked and tested them. One worker used a special flashlight to search for fluid leaks from a Verado V6 4-stroke. As the engine nears completion on the assembly line it is put through durability testing under a protective Plexiglas hood, which reduces sound and increases safety for the test operator.

As the tour proceeded, I watched automated dollies carry powerheads to their next stop on the line. A few minutes later, we stopped in front of a large fence cage. Inside, robotic equipment — dormant at that moment — soon would begin inserting and tightening to predetermined torque levels the assembly bolts of a Verado V6.

“The robotics take care of the pre-torque, the post-torque and angle of the bolts,” King says. “It takes about three to four hours to assemble the average engine here.”

We left assembly and headed to the new high-pressure 20,000-square-foot aluminum die-cast plant.

“We’ve been in production for about six months,” Mike Meyer, die-cast foundry general manager, says before we enter the building. “You won’t be able to tell it is even six months old because of the meticulous housekeeping. It’ll look like this for the next 35 years.”

Workers wore flame-retardant blue jackets. “Don’t touch anything — it could be 200 to 300 degrees,” Meyer says.

There were two new 2,500-ton high-pressure die-cast machines here and there was an empty spot for a third new machine. Casting for drive shafts and inline cylinder blocks is done here, Meyer says.

“All of the work takes place here — the casting, the trimming and the finishing,” he says.

The plant tours ended, but we had one more stop — Mercury’s new museum. I quickly learned that founder Carl Kiekhaefer built more than marine engines. He also was responsible for chainsaws, lawnmowers, snowmobiles and a Corvette engine.

The museum opened in the spring. Mercury’s forays into non-marine products also included motorized bikes (Kiekhaefer used one to get around during the workday). Mercury was founded in January 1939 when Kiekhaefer bought the bankrupt Cedarburg Manufacturing Co., the maker of Thor outboards.

The perimeter of the room houses a history of Mercury engines, beginning in the 1930s and 1940s. Displays for each decade encompass the room’s outer edge.

The first marine engines I saw were a few of the K series outboards (the fleet included K1, K2, K3, K4 and K5 engines) that were introduced at the 1940 New York Boat Show. The last engine: Mercury’s new 115-hp 4-stroke outboard — with the signatures of the employees who built it covering the cowling. I counted the outboards on display: 30.

Mercury engines played roles in some major historical eras. The 1943 5-hp Mercury KB7A was the motor that powered Mercury-Disston chainsaws, which the Army Corps of Engineers used. One of the chainsaw displays says: “By the end of World War II, Kiekhaefer was the largest manufacturer of chainsaws in the world.”

These machines helped keep Mercury working during the lean years of the war. The company also made an 80-hp 4-cycle engine that was used for drone target aircraft.

This article originally appeared in the August 2014 issue.



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