Walker Engineering has been making diesels breathe better for more than two decades.
I used to crew on a 43-foot sportfisherman that was powered with twin 625-hp Detroit Diesel 6V-92s, and those engines were tank-like. In fact, the current owner of that boat has 3,000-plus hours on those original motors and they’re still going strong. But after every day-long trip, our crew’s ritual at the dock was to break out the brushes and start scrubbing, trying to find out if the boat’s name was still somewhere under her soot-stained transom. And when we finished with that, we had to change the oil-absorbent pads under both motors.
Engine technology has advanced quite a bit since then. Modern common-rail diesels are both cleaner and more efficient right out of the box, which is why I’ve noticed a lot fewer dirty transoms. While new engine technologies get much of the credit, there is an unsung hero in this increased-efficiency equation: filters. Specifically, Walker engineering has been applying its air- and fuel-filter technology to improve overall engine performance for more than 20 years.
Take, for instance, the ubiquitous Walker Airsep air filter, which was the company’s first marine-diesel product. It’s that reddish filter that’s probably sitting atop your motors. Unlike conventional paper filters, the Airsep is comprised of what Walker calls “multilayer proprietary media,” which allows for increased air flow, is washable, and is coated with a proprietary oil (that’s what makes the filter red) to prevent the passage of dirt and dust. The filter also captures oil mist that would otherwise coat everything in the engine room. An Airsep offering typically lasts for two to three seasons while tolerating a humid environment without getting restricted. This makes it a much better purchase than a paper filter.
The owner of that 43 I crewed on had not only retrofitted his Detroits with Airseps but also Walker Fuelseps, which install in the fuel lines between the fuel-water separators and the engines’ primary filters. He noticed improvements right away: The engines ran significantly cleaner (less smoke, less smell), and he could actually read the name on the back of the transom after a long day of trolling for marlin. In addition, after burning through a few tanks of fuel, the owner told me that he was seeing an average fuel savings of five percent. When you’re going through thousands of gallons of diesel a season, that kind of improvement adds up.
But while Airseps and Fuelseps (and Algaeseps, which separate water and contaminants from fuel), can be found on many vessels, Walker is looking to further expand its ability to increase engine performance by recently introducing updated retrofit Airsep filter kits for older motors, as well as some completely new offerings.
One of the upgrades is the Airsep CCE, an improved filter for older Detroit/MTU Series 2000 DDEC and MDEC engines. Traditional Airseps are sealed without a way to service the internal media, but the CCE was designed to capture very fine oil particles to keep the intakes cleaner and provide easy access when you need to replace the filter media after approximately 500 to 750 hours. If this wasn’t possible, crankcase pressure would likely increase until the filter pack was changed.
Walker says that the CCE unit removes crankcase fumes via vacuum, lowering crankcase pressure and capturing oil that would otherwise go into the intake or into your engine room. It then traps the large oil particles (vapor) and turns them back into a liquid that drains via a line that leads back into the oil pan. The remaining smaller oil particles are captured in the main filter, which keeps turbochargers and air intakes clean and in turn, reduces smoke and provides a fuel savings. Pricing for these Airseps starts at about $495 for gensets and around $895 per turbo for propulsion diesels.
Walker has also developed high-performance air filters for MAN and Volvo Penta diesels. Like its other offerings, these new filters replace the stock paper units, which are actually derived from non-marine applications, and allow for higher air flow with less restriction, reduce the risk of clogging due to moisture and water, and are washable and reusable. The new models will fit MANs from 730 hp to 1,800 hp and Volvo Pentas from 130 hp to 1,000 hp.
In addition to improving operating efficiency, Walker has been working on reducing engine-related sound by developing a filter called Everquiet that has a built-in air-intake silencer. Walker claims this setup reduces engine-intake noise by five or more decibels.
Improving engine performance is obviously a focus of Walker Engineering, but the company has also developed products for Volvo Penta engine owners who want to upgrade the visual appeal of their engine room. Taking a page from sleek-looking high-performance motorcycles and classic cars, the company has created “dress-up kits” consisting of highly polished stainless steel air-filter covers and cowlings. They’re designed for Volvo D4s and D6s and will soon be available for that company’s IPSII and IPSIII configurations. They come in three versions.
The entry-level kit is the Performance Package, which is priced at $199.95 and includes a high-gloss black air-filter cover and a high-performance Walker air filter. Next is the Captain’s Package, priced at $799.95. In addition to a polished stainless steel air-filter cover, it includes two polished oil-filter covers, a fuel-filter accent cover, and an accent kit for the top of the motor.
Walker’s top-of-the-line kit, the Admiral’s Package, will cost you $995.00 and contains all of the elements of the Captain’s kit with one exception: Instead of the three-piece top-accent pieces, you get an entire high-polished stainless steel engine cowling. An optional stainless steel sea strainer adds $249.95 to the price.
So whether you’re looking for an easy-to-read transom or some engine-room bling, Walker has a product to do the job. And now that spring is finally here, what better time to give your engine room a fresh look and some fresh air?
CONTACT: Walker Engineering (818) 252-7788. www.walkerairsep.com.
This article originally appeared in the April 2010 issue of Power & Motoryacht magazine.