Upgrade Your Yamaha Outboard with the Sierra 18-79957 VST Kit

Keep your Yamaha outboard running smoothly on the water with the Sierra 18-79957 VST kit, designed specifically for F50 through F90 and T50 through T60 models. This high-quality vapor separator tank assembly replaces worn-out components in your fuel system, ensuring reliable performance during long days of boating, fishing, or cruising. Unlike basic replacements, this kit delivers OEM-level fit and function while standing up to the harsh marine environment, from saltwater spray to high-RPM demands.

Boat owners trust Sierra engine parts for their precision engineering and durability. The 18-79957 isn't just a drop-in part—it's a complete kit that addresses common fuel vapor issues, preventing hesitation, stalling, or poor idling that plague older outboards. Whether you're prepping for the season or troubleshooting fuel delivery problems, this VST kit restores factory specs for optimal throttle response and efficiency.

Key Features and Benefits

• Complete VST Assembly: Includes the vapor separator tank, fuel filter, pump components, and necessary hardware for a full rebuild—no hunting for individual pieces.
• Corrosion-Resistant Materials: Built with marine-grade composites and seals that resist ethanol-blended fuels and UV exposure, extending service life in tough conditions.
• Precise Fitment: Engineered to match Yamaha's original dimensions, ensuring seamless integration without modifications.
• Improved Fuel Flow: Eliminates vapor lock and air intrusion, leading to smoother starts, consistent power, and better fuel economy.
• Easy Maintenance Access: Transparent filter housing lets you monitor fuel clarity at a glance, simplifying routine checks.

Many users report noticeable improvements in mid-range acceleration after installation, making it ideal for towing skiers or powering through choppy waters.

Perfect Compatibility for Yamaha Models

The Sierra 18-79957 VST kit fits a range of popular Yamaha 4-stroke outboards:

• F50, F60, F70, F80, F90 (various horsepower variants)
• T50, T60 (T-series tillers)

Before installing, confirm your engine's model and serial number match the kit's specifications. This ensures plug-and-play compatibility, saving you time and frustration at the dock.

Step-by-Step Installation Guide

Replacing your VST is a straightforward DIY job that takes about 1-2 hours with basic tools. Here's a quick overview:

1. Disconnect the battery and relieve fuel system pressure.
2. Remove the cowling and locate the VST assembly on the starboard side.
3. Disconnect fuel lines, electrical connectors, and mounting bolts—label hoses for easy reassembly.
4. Install the new Sierra kit, torque fittings to spec, and prime the system.
5. Test run the engine on muffs before heading out.

Pro tip: Flush the fuel lines beforehand to avoid contaminating the new filter. Always work in a well-ventilated area away from sparks.

Why Sierra Over Other Brands?

Sierra has built a reputation for affordable, reliable aftermarket marine parts that meet or exceed ABYC standards. The 18-79957 VST kit undergoes rigorous testing for pressure, flow, and leak resistance, giving you peace of mind on every outing. It's a smart choice for budget-conscious boaters who demand performance without compromise.

Maintenance Tips for Longevity

To maximize the life of your new VST:

• Inspect and replace the fuel filter every 100 hours or annually.
• Use fuel stabilizers for winter storage to prevent varnish buildup.
• Monitor for ethanol-related issues by running non-ethanol fuel when possible.
• Check connections seasonally for cracks or looseness.

Regular upkeep like this keeps your Yamaha outboard firing on all cylinders season after season.