Fishermen's News - The Advocate for the Commercial Fisherman

About Your New Engine…

 


The last ten years or so, the world of diesel engines has dramatically changed, some for the good, some for the bad. Vessel owners in the past were able to purchase engines capable of support by local mechanics on the West Coast and Alaska. I recall, as a young fellow visiting Cordova’s Harbor, asking a fisherman why so many boats were powered by Detroit Diesels, a noisy, 2-cycle engine, fuel thirsty, and notorious for oil leaks. The old fellow answered, “Sonny, you can find a drunk in any bar in any port in Alaska that knows how to overhaul them.” Enter the EPA (Environmental Protection Agency) and the new generation of electronically controlled engines. Servicing the electronic engines requires a specially trained mechanic, and computer equipment capable of monitoring the engines functions. The software needed for the computer equipment can cost several thousand dollars, and can require frequent costly updates. This somewhat eliminates the local shade tree mechanics from providing viable service.

Almost all new engines are now electronically controlled. The engine has a computer (ECU) that monitors all sorts of engine functions, such as air intake temperature, load demand, fuel pressure feed, exhaust temperature, oil pressure, engine RPM’s, and more. The older mechanically fueled engines were controlled by a throttle and engine governor. The new generation engines have electronically controlled injectors, capable of firing multiple bursts of fuel in milliseconds, avoiding over fueling. The engines are designed to minimally smoke in order to meet new stringent emissions regulations of the EPA. Unburned fuel makes smoke, as witnessed on older vessels starting up, or leaving harbor. A benefit to this technology is generally better fuel efficiency.

Engine warranties should be thoroughly considered when selecting an engine. If a local engine shop has factory trained and authorized service technicians, it makes more sense to select their supported engine brand. Flying a mechanic from Seattle or other major hub for legitimate warranty repair at an Alaskan port could mean high expense, and added loss of fishing time.

The multitude of electronic sensors, wiring, and related connections are vulnerable in a marine environment. A little moisture in the wrong place can cause a sensor reading to put the engine into a fault condition, causing partial or total shutdown. Engine manufacturers have improved these components and fewer horror stories are being heard. Using dielectric grease, if approved by the engine manufacturer, might be a way to minimize this problem.

Repowering a vessel still offers some choices regarding engine types. Several engine manufacturers offer SRO (service replacement only) engines, meaning you could replace an older mechanically injected engine with an equal or newer engine. A requirement for this option is using the old engine as a core. Depending on the location of the repower, such as a remote Alaskan port, the engine seller may require the return of the engine, or simply photographic evidence the core has been destroyed. Photos may be required of a hole bored into the block adjacent to the serial number, and the crankshaft and journals scored beyond repair. Cummins and Isuzu are among several manufacturers offering such a program.

Boats fishing in California may not be eligible for this option. The California Air Resources Board, it seems, is requiring repowers to be of the latest tier. For several years, the State of California had an aggressive program assisting fishermen in upgrading their propulsion and generator engines. CARB officials at various locations were occasionally differing in opinions on which engines were allowable.

New generations of engines tend to be more compact, offering a higher weight to horsepower ratio from the more efficient fuel delivery. Less weight means more payload capacity in a vessel. Repowering could mean a little more space in the engine room. Another feature common in the newer engines is much quieter operation, with much less vibration.

Control panels are generally digital, and usually take less space than the older analog panels, with a screen the size of a small computer tablet or large cell phone. Some panels may only monitor a couple of functions, but allow scrolling through a menu of monitors with a push of a button. Real time fuel consumption is one great feature usually offered. This allows the skipper to find the “Sweet” spot, where the best economy can be found at cruise.

Throttle controls on some electronic engines might be as simple as a dial or knob on the dash panel. Engine speed is controlled by a potentiometer, usually located on the side of the engine. Traditional throttle cable control can be an option if a lever type potentiometer is used.

Electronic fuel injectors require extremely clean fuel. Though the engines may be fitted with a water separator fuel system, installing a pre-filter system such as a Racor filter is recommended. Electronic injectors quickly deteriorate due to the presence of water, an abrasive element. Replacement injectors typically cost more than a thousand dollars each. Replacement of the injectors usually requires reprogramming of the ECU by a technician with computer equipment, due to the precise tolerances required for a well controlled ignition, adding to the costs, so good filtration is cheap insurance. Adding a water alarm to the filter system will add protection, as the filters are designed to take out incidental water. Should the filters encounter more water than they’re capable of capturing, the water will pass through to the engine.

Power takeoff from an engine (PTO) should be investigated, and gear boxes are another point of concern when repowering. Engine flywheel housings might be different on a new engine. If the gearbox is in good condition, adapter rings might be a solution to adaptation. Many of the older Detroit Diesel Engines, for example, were SAE 1, where a new engine, comparable in horsepower might be SAE 2 or even SAE 3. It’s generally a good idea to replace the damper plate. Horsepower rating of the gearbox should also be carefully checked. Higher horsepower output of a new engine might exceed the capacity of the old box, resulting in early failure. It’s usually a good idea, if using an old gearbox, to have it serviced or overhauled by a certified mechanic. Clutch packs or bearings might be worn and in need of replacement.

A new engine might affect propeller performance. It’s a good idea to consult one of the propeller houses to determine proper propeller size, as well as gear ratio. The propeller people have computer software that considers hull type, weight of the boat, engine horsepower, and gear ratio contemplated, eliminating some of the guesswork regarding wheel size. If water jet propulsion is being used, the jet manufacturer should be consulted to determine if the impeller pitch requires adjustment.

As always, buying a used engine for a repower can be disastrous. Countless times, the good bargain found on Craigslist or other Internet web sites has turned out to be misrepresented. Some fishermen have received equipment barely worth scrap metal prices. Trying to recover such an investment can be costly or fruitless, unless the seller is local. It should be noted many of the larger engine sellers offer remanufactured engines, with legitimate warranties and an implied high level of quality.

Consulting a reputable engine seller can minimize problems with engine selection, whether new vessel construction, or performing a repower. The seller should be aware of applicable EPA regulations and competently assist in proper selection of an engine.

David Rowland has been involved in the marine trades for thirty-five years, with gas and diesel propulsion engines, high and low pressure water jets, marine diesel generators, and related equipment. Living in Alaska for fifteen years, he had the opportunity to visit nearly every port in Alaska. Currently, he is involved in marine equipment, located near Anacortes, Washington.

 
 

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