Fuel Injector Insights

When testing fuel injector coils, there are two primary methods: a resistance check and an insulation check. However, insulation testing applies only to piezoelectric injectors; it cannot be performed on GDI or Port injectors. More on that below.  This distinction is important, as an injector may pass a resistance check yet still be faulty. Here […]

Should You Add Oil To The Fuel For Evinrude E-TEC Engines To Lubricate The Injectors? Good question — I know why you’re asking. Some owners of direct-injected two-strokes (including Evinrude E-TECs) wonder if adding oil to the fuel might help lubricate the injectors or reduce wear. The short answer from BRP/Evinrude: The “Official response is […]

A leaking fuel injector can cause a range of drivability issues and even long-term engine damage if not addressed. Symptoms depend on whether the leak is internal (injector dribbling into the cylinder when it should be closed) or external (fuel leaking outside the injector body, seal, or rail). Key Symptoms of a Leaking Fuel Injector […]

Regarding E-TEC Injector Injector Flow Post Cleaning immediately after ultrasonic cleaning, then increasing hours to days later, typically occurs due to the movement and resettlement of internal debris or atmospheric factors. Reasons for E-TEC Flow Decrease Post Cleaning then Increase Later in time: Gradual Flushing: As the engine is driven, the constant high-pressure fuel flow […]

What Injector Cleaning & Testing Can Fix (Preventative) Varnish & gum deposits from aged fuel. Ultrasonic + solvent flushing can dissolve and clear it. Minor clogging from dirt/silt. Backflushing and multiple cycles can restore proper spray pattern and flow. Spray quality issues caused by residue. A clean pintle/needle = finer atomization, smoother running. Filter baskets […]

Here’s a breakdown of what wears out an E-TEC Injector or causes them to to fail and drift out of spec over time. E-TEC injectors are very different from port injectors or even automotive GDI injectors. They are precision metering devices with multiple internal wear points, and the biggest issues are not about lubrication. 1. […]

How to Troubleshoot Evinrude E-TEC Engine Common question: “What are some reasons for an Evinrude E-TEC motor having a mid RPM bog?” *See our ‘E-TEC checklist.PDF’ at the bottom.* A mid-RPM bog on an Evinrude E-TEC is something we get asked a lot about and usually a sign that something is disrupting combustion efficiency or […]

See what a worst case clogged E-TEC injector looks like as ta result of prior improper installation of the injector into the manifold. Waiting too long between cleaning cycles can lead to permanently blocked E-TEC Injectors.  

Are Grey Optimax Air Injector the Same As The Black Ones : No, the grey and black Optimax air injectors are not the same. While they perform a similar function, they are distinct parts and are not interchangeable. Here’s what you need to know: Color is critical: For Mercury Optimax air injectors, the color of the […]

E-TEC (Electronic Fuel Injection Technology) fuel injectors are part of a direct fuel injection system used in certain outboard engines, like those from Evinrude.

E-TEC Injector Cleaning: Evinrude E-TEC fuel injectors should generally be professionally cleaned every 300–500 engine hours, or every 1–2 years, depending on usage conditions. However, here’s a more specific breakdown: Recommended Cleaning Intervals: Heavy Use / Saltwater / Poor Fuel Quality: Every 250–300 hours Normal Use / Freshwater: Every 400–500 hours Storage or Long-Term Idle: […]

How Optimax Air Injectors Work: Optimax air injectors do not “pulse” in the traditional sense like fuel injectors do. In the Mercury Optimax direct injection system, air injectors deliver compressed air into the combustion chamber at high pressure, working in tandem with the fuel injectors. The fuel injectors spray fuel into the combustion chamber after […]