Fuel System

Why Fuel Care is Important

Even more than the gas in your car, the gas in your boat needs special care to keep your engine running at peak performance. Gasoline begins to go bad within a few weeks. When left untreated, some of the fuel components begin to oxidize and form a gum-like substance, which settles in fuel lines and tanks, carburetors, and injectors. When you try to burn this fuel, deposits can form in the combustion chamber. Over time, these deposits build up and reduce your engine's performance.

Fuel additives keep your fuel optimized, protect your fuel system, and remove any leftover deposits. With the Quicksilver Fuel Care System, you can trust that you're using products that are specially formulated - by the same people who design Mercury engines.

Although fuel additives can help prevent some fuel system problems, there are other ways to help prevent fuel related problems such as:

Purchase quality fuel from trusted sources:
Sometimes fuel is contaminated before it's pumped into your tank. Buy fuel from stores that take care of underground tanks and perform the proper maintenance.

Periodically check fuel filters and fuel tanks for sediment and water:
Over time, non-ethanol-blended fuel can leave behind sediment that collects inside the walls of your fuel tank. When ethanol-blended gasoline is first used, it can strip away the build-up in your tank. Fuel filters help prevent the sediment--that can cause engine damage--from entering your engine.

Water can enter the fuel tank in a number of ways. Your local marine dealer has tools to help check for water in the fuel tank. If water is found, most engine manufacturers recommend removing all of the bad fuel and refilling with new, fresh gas.

Keep up-to-date with your engine manufacturer's maintenance schedules:
To get the most from your engine, follow the maintenance schedules recommended by your engine manufacturer.

The Quicksilver Fuel Care System

With Quicksilver, there's no need to guess about which products are best to keep your engine's fuel in top form. The Quicksilver Fuel Care System is one complete system - specially formulated by the people who made your engine, with decades of experience on all kinds of engines - to help it run its best. It's as easy as 1, 2, 3 - regardless of whether you use ethanol- or non-ethanol-blended fuels.

QUICKSILVER PRODUCTS

1. Quickare Fuel Treatment

Quickare is a complete fuel treatment that can be used in all grades of gasoline, including ethanol blends.

  • When used at every fill-up, it helps prevent common fuel system problems such as:
  • Fuel oxidation and breakdown
  • Moisture and corrosion
  • Gum and varnish build-up
  • Phase separation
2. Quickleen Engine & Fuel Care System Cleaner

Quickleen is a deep cleaning treatment that should be used periodically.

Aggressive cleaners work to quickly and thoroughly remove carbon deposits from carburetors and injectors, intake valves, spark plugs, piston crowns and cylinder heads.

3. Quickstor Fuel Stabilizer

Add Quickstor to fuel before storing your engine to ensure your fuel is ready to go at the start of the next season.

Use Quickare at every fill-up to:

  • Maximize engine performance with all grades of gasoline
  • Help control corrosion, gum and varnish build-up, and phase separation associated with ethanol-blended fuel
  • Help control moisture and corrosion problems associated with non-ethanol fuel
  • Clean up existing varnish and gum deposits from fuel lines, tanks, carburetors and injectors, intake valves, and spark plugs
  • Keep fuel fresh between fill-ups - up to 12 months

1 ounce treats 10 gallons - 12 ounce bottle treats 120 gallons

Use Quckleen to:

  • Prevent engine knocking and piston seize-up
  • Extend spark plug life

This product does not contain fuel stabilizers. Use with Quickare to prevent fuel breakdown and oxidation.

1 ounce treats 5 gallons - 12 ounce bottle treats 60 gallons

Use Quicksilver to:

  • Prevent regular and ethanol-blended fuel from breaking down and oxidizing
  • Prevent fuel system corrosion
  • Prevent gum and varnish from forming in the fuel and settling in fuel lines and tanks, carburetors and injectors
  • Keep injectors and carburetor lubricated
  • Stabilize fuel for up to a year

1 ounce treats 5 gallons - 12 ounce bottle treats 60 gallons

Portable Fuel System

The Environmental Protection Agency (EPA) will require portable fuel systems that are produced after January 1, 2011 for use with outboard engines to remain fully sealed (pressurized) up to 34.4 kPa (5.0 psi). These tanks may contain the following:

  • An air inlet that opens to allow air to enter as the fuel is drawn out of the tank.
  • An air outlet that opens (vents) to the atmosphere if pressure exceeds 34.4 kPa (5.0 psi).

Fuel Demand Valve (FDV) Requirement

Whenever a pressurized fuel tank is used, a fuel demand valve is required to be installed in the fuel hose between the fuel tank and primer bulb. The fuel demand valve prevents pressurized fuel from entering the engine and causing a fuel system overflow or possible fuel spillage.


fuel demand valve

The fuel demand valve has a manual release. The manual release can be used (pushed in) to open (bypass) the valve in case of a fuel blockage in the valve.

  1. Fuel hose between the fuel tank and primer bulb
  2. Manual Release
  3. Vent/water drain holes

Mercury Marine's Pressurized Portable Fuel Tank

Mercury Marine has created a new portable pressurized fuel tank that meets the preceding EPA requirements. These fuel tanks are available as an accessory or are provided with certain portable outboard models.

Special Features Of The Portable Fuel Tank

  • The fuel tank has a two-way valve which allows air to enter the tank as the fuel is drawn to the engine, and also opens to vent to the atmosphere if internal pressure in the tank exceeds 34.4 kPa (5.0 psi). A hissing noise may be heard as the tank vents to the atmosphere. This is normal.
  • The fuel tank includes a fuel demand valve that prevents pressurized fuel from entering the engine and causing a fuel system overflow or possible fuel spillage.
  • When installing the fuel tank cap, turn the cap to the right until you hear a click. This signals that the fuel cap is fully seated. A built-in device prevents overtightening.
  • The fuel tank has a manual vent screw which should be closed for transportation and open for operation and cap removal.

Since sealed fuel tanks are not openly vented, they will expand and contract as the fuel expands and contracts during heating and cooling cycles of the outside air. This is normal.


Fuel Cap

Removing The Fuel Cap

  1. Fuel Cap
  2. Manual vent screw
  3. Tab lock

IMPORTANT: contents may be under pressure. Rotate the fuel cap 1/4 turn to relieve pressure before opening.

  1. Open the manual vent screw on top of the fuel cap
  2. Turn the cap until it contacts the tab lock.
  3. Press down on the tab lock. Rotate the fuel cap 1/4 turn to relieve the pressure.
  4. Press down on the tab lock again and remove the cap.

Directions For Using The Pressurized Portable Fuel Tank

  1. When installing the fuel tank cap, turn the cap to the right until you hear a click. This signals that the fuel cap is fully seated. A built-in device prevents over-tightening.
  2. Open the manual vent screw on top of the cap for operation and cap removal. Close the manual vent screw for transportation.
  3. For fuel hoses that have quick disconnects, disconnect the fuel line from the engine or fuel tank when not in use.
  4. Follow Filling the Fuel Tank instructions in your Operation, Maintenance and Warranty manual for refueling.

FAQs

Do I need to use a fuel demand valve?
Yes, when the tank is pressurized.

How will I know if I have a pressurized fuel system?
It will be indicated by the tank cap (will ratchet similar to automotive).

Does the fuel demand valve need to be in that position in the fuel line assembly?
No, it can be anywhere as long as it's between the fuel tank and the primer bulb in the fuel line assembly.

If I want to fill the tank, what should I do if I notice the tank is under pressure?
Rotate the fuel cap 1/4 turn to release pressure (see the four-step process above or refer to your Operation, Maintenance and Warranty manual).

Does the fuel demand valve have to be in a certain position (i.e. always facing up) to work?
It will function in any position.

What is the purpose of the holes in the top of the fuel demand valve?
The purpose is for venting the back side of the valve and water drainage away from the fuel demand valve diaphragm; the valve can be opened by depressing valve mechanism through slot on cover (manual over ride).

Is it ok to use 10% ethanol fuel with the fuel demand valve?
Yes.

Fuel Lines and Fittings

Materials make the difference. Quicksilver fuel lines and fittings are made of materials that are UV resistant and prevent hardening. All materials must meet Mercury’s strict engineering specifications for UV hardening resistance, alcohol absorption, fuel flow restriction and leakage. The result is a product that lasts longer and is more reliable.

Quicksilver primer bulb

Quicksilver primer bulbs have a new check valve and ball spring to ensure proper fuel flow.

Competitor primer bulb

Competitor primer bulbs have an inferior check valve that can stick when it’s closed. The engine will stall because fuel cannot flow properly.

Water separating fuel filters

Water in the fuel system can cause poor engine performance and can even cause engine damage. In addition to fuel additives, water separating fuel filters also offer a great line of defense in keeping your fuel system free of water and other impurities.

Quickare, Quickleen, and Quickstor

Quicksilver fuel filters are constructed of the highest quality materials. Their unique filtration system screens out particles smaller that 1/1000th of an inch. The metal shell is over 50% thicker than conventional filters. The inside of the filter is epoxy-coated so it doesn’t rust.