Engine Review: Evinrude E-TEC 50 outboard motor review

Engine Review

Originally published in TrailerBoat #264, December 2010 / January 2011.

When my local Evinrude E-TEC dealer contacted me about reviewing an E-TEC 50 outboard motor, the test was made all the more interesting in that it was a re-power engine for a 1998 Quintrex 435 Top Ender. The boat’s owner had originally bought the Quintrex along with a 50hp four-stroke outboard, but as the engine clocked up the hours it became increasingly expensive to service.

Instead of opting for another four-stroke boat engine, the owner chose an E-TEC 50. This decision based on the three-year or 300-hours no-service period, and that essentially being a two-stroke engine there was a lot less to go wrong. The E-TEC 50 outboard has no belts to stretch or fail and uses the same pistons and con rods as E-TEC outboards from 40 to 200hp. One of my colleagues, who has owned an E-TEC 50 engine on his Webster Twinfisher for some time now, says it’s been very reliable during countless fishing trips.

The E-TEC 50 outboard is the middle of a trio of twin-cylinder models from 40 to 60hp, with only the E-TEC 60 differing in that it has a two-stage exhaust system to give increased top-end power. Like its counterparts, the Evinrude E-TEC 50 outboard has a mix of stratified and homogenous combustion with the changeover point at 1500rpm.

When operating on stratified mode the fuel is sprayed into the combustion chamber in a narrow conical shape with the overall combustion air/fuel ratio being as lean as 70:1. On homogenous mode the A/F ratio is around 14.7:1, which is necessary to provide the torque to plane a hull. Depending on the load requirements and engine rev rate, the fuel-injection pressure varies from 500 to 700psi (34 to 48bar) achieved through electrically-controlled unit injectors.

Oil is injected by an electric pump to only where it’s needed and when the engine is set up to run on fully synthetic Evinrude XD100 oil the fuel/oil ratios are very lean.

The variable voltage under flywheel alternator produces up to 25amp of dedicated battery charging current, while the Speed Adjusting Failsafe Electronics (SAFE system) automatically reduces engine rpm to a “limp home” mode in the event of no oil or engine overheat situations. The engine can also be started manually in the event of a flat battery as the EFI system doesn’t require a battery to function.

PERFORMANCE

Spinning a 15in pitch stainless steel Viper prop, the review Evinrude E-TEC 50 was a perfect match for the Top Ender and had blistering acceleration across its entire rev range. This was despite the fact that it was pushing 700kg including two adults, the owner’s bowmount Minn Kota trolling motor and deep cycle battery, and a full underfloor fuel tank. It started instantly hot or cold and despite running on a rich “break-in” mix (first two hours) there was no oil smoke, and only a slight oil smell when backing upwind. Providing the antiventilation plate was kept at least three quarters immersed, power astern was good and the multifunction tiller arm was very user-friendly. Vibration levels were surprisingly low for a big twin, even when trolling.

Minimum planing speed with the Evinrude E-TEC 50 was 12.4kts (23.0kmh) doing 3500rpm. 16.6kts (30.8kmh) was attained at 4000rpm, drinking 8.9lt/h. WOT gave 27.5kts (51.0kmh) at 5720rpm at 19.3lt/h.

Through full-lock figure-of-eight turns at 4000rpm no prop ventilation occurred. However, due to the prop steer torque from the massive gearcase reduction ratio the steering was very heavy until the outboard leg was trimmed out slightly. At WOT we could hold a normal conversation at the helm. How about that?

SERVICING AND WARRANTY

Powerhead access is tight but the lower cowl splits in half for full servicing. Unlike the direct DFI two-stroke competition, the upper cowl must be removed to access the integral oil tank. It’s a sensible design that prevents salt spray from reaching the tank cap. Although servicing is not essential for the first 300 hours or three years, I recommend changing the gear oil annually. The recreational-usage warranty is five years.

COMPETING OUTBOARDS

EVINRUDE E-TEC 50 TILLER STEER BEST FEATURES

•             Gutsy and fuel efficient.

•             Quiet and user-friendly.

•             Very low servicing requirements.

•             Great spares availability.

Originally published in TrailerBoat #264, December 2010 / January 2011. Why not subscribe to Trade-a-Boat today?