Evinrude eTec Fuel System

BRP Evinrude eTec 250 HO high output red stainless propeller

Evinrude eTec History

Originally launched 2003, 40 - 90hp eTec motors were the first re-designed outboard motors released by Bombardier Recreational Products, after their bankruptcy acquisition of the Outboard Marine Corporation, in 2001. The eTec motors were released under the Evinrude brand, as a replacement to the previous Ficht motors, which were plagued with problems from the start, and often considered to be a large factor in the bankruptcy of OMC. During this time period BRP's other outboard brand, Johnson continued to sell 4-stroke outboards. These Johnson outboards were sourced from Suzuki Marine, and painted Johnson colors. All along BRP made it clear that their focus was on the eTec 2-stroke technology, and that vision remains true today. 

Evinrude Ficht and eTec Differences

What is the difference between Evinrude Ficht and eTec motors? Before we get into how the Evinrude e-Tec fuel system works, we will first take a look at it's predecessor the OMC Ficht Direct-Injection system. The systems carry many similarities, with the main difference being in the injector itself. Both the Ficht and eTec injectors are considerably different from conventional auto injectors. Rather than being an open-close valve, using fuel pump pressure for injection, the Ficht and e-Tec injectors are both an internal pump of sorts. These internal pumps take the 25-35psi pressure fuel supplied by the fuel pump and re-pressurize it to extreme pressures, as much as 600psi on the e-Tec. On the Ficht RAM Direct injection motors the fuel delivery is executed by a mechanical solenoid, the same style that would be seen in a typical marine fuel injector, only larger. This coil is only able to operate on a fully open, or fully closed basis. Once the solenoid is shut off, it is returned to it's resting position by a mechanical spring. Because of these 2 flaws the Ficht injectors are not able deliver fuel with the accuracy of the eTec. These faults in the injectors are one of the reasons that the Ficht motor failures are so common. The eTec Direct Injectors take this same concept, only they have re-designed the injector with a voice coil instead of a solenoid. This voice coil operates the same way that a stereo speaker works, and thus is able to more accurately regulate the amount of fuel it is injecting. In addition they have also replaced the ball and spring plunger, with a one piece plunger that is formed to distribute the fuel in a more even manner to the pintle.

How the Evinrude eTec Fuel System Works

The eTec's fuel system starts out quite similar to other motors on the market, including Optimax and 4-stroke product. The fuel is pulled from the tank by the pulse operated lift pump. It is then delivered to the VST or Vapor Separation Tank. From there it is pumped by an electric fuel pump to the direct injectors. This is where the similarities end however. The Evinrude eTec outboards have 2 electrical circuits, a conventional 12 volt circuit, as well as a 55 volt output for the fuel injectors. This 55 volt circuit also powers the high pressure electric fuel pump on some models. The power for both of those circuits is supplied from the stator to the Engine Management Module. The EMM has an internal voltage regulator/rectifier that converts the AC power from the stator into 12v power for battery charging and other 12V functions, as well as the 55v circuit is used for fuel injection, and ignition circuits. The Engine Management Module is cooled by seawater provided by the water pump impeller.

The EMM controls all of the following processes and functions:

• Alternator output; 55 V and 12 V

• Fuel and ignition timing and duration

• Fuel injector activation

• Oil injector pump activation

• Electric fuel pump control

• Idle speed control

• RPM limiter

• Electrical circuit monitoring

• Service code creation and storage

• Warning system activation

• ROM verification, self-test

• Choke-less cold starting

• Output of diagnostic data

• Tachometer signal

• RPM profile and engine hours

• Oiling ratios

• Exhaust water valve activation (60 - 65 HP)

The EMM controls the firing of the injectors by switching the ground circuit internally. The fuel is then injected into the cylinders at as much as 600psi. Each eTec injector has its own flow coefficient file. These coefficient files are assigned at the factory based off of that particular injector's flow rate. These fuel injector calibrations are then loaded onto the EMM so that it knows exactly how much fuel each injector can flow, and adjusts the open time based on this. Because of this extreme pressure and the design of the pintle the injectors have a great atomization, and extremely consistent flow which is why the eTec has great fuel economy as well as great acceleration thought the power curve.

Evinrude eTec Injector Cleaning

For these exact reasons the Evinrude needs to have extremely clean fuel. Any any water or debris in fuel can clog the fuel injectors tiny filters, and in some cases crush the secondary filter. It is very important to have your injectors cleaned if you have ran bad fuel through your boat motor. It is also equally important that when removing your injectors you number the exact location each was removed from. If this is not done, the injectors will not be able to be placed in their correct spots, and the dealer will need to re-program your EMM with the fuel injector calibration file.