Contact Us
My Account
Search Over 1 Million OEM Parts
Most parts in stock- Same day fulfillment

Mercury/Mariner 4-Stroke Winterization

Repair Time: 30 to 60 mins
Repair Difficulty: Easy
Mercury/Mariner 4-Stroke Winterization
Mercury Marine Outboard




The major consideration in preparing your outboard for storage is to protect it from rust, corrosion, and damage caused by freezing of trapped water.

The following storage procedures should be followed to prepare your outboard for out-of-season storage or prolonged storage (two months or longer).

Never start or run your outboard (even momentarily) without water circulating through the cooling water intake in the gearcase to prevent damage to the water pump (running dry) or overheating the engine.

Fuel System

Gasoline containing alcohol (ethanol or methanol) can cause a formation of acid during storage and can damage the fuel system. If the gasoline being used contains alcohol, it is advisable to drain as much of the remaining gasoline as possible from the fuel tank, remote fuel line, and engine fuel system.

Fill the fuel system (tank, hoses, fuel pump, and carburetor) with treated (stabilized) fuel to help prevent formation of varnish and gum. Proceed with following instructions.

  1. Portable Fuel Tank - Pour the required amount of Quicksilver Gasoline Stabilizer (follow instructions on container) into fuel tank. Tip fuel tank back and forth to mix stabilizer with the fuel.

  2. Permanently Installed Fuel Tank - Pour the required amount of Quicksilver Gasoline Stabilizer (follow instructions on container) into a separate container and mix with approx. one quartof gasoline. Pour this mixture into fuel tank.

  3. Place the outboard in water or connect flushing attachment for circulating cooling water. Run the engine for ten minutes to allow treated fuel to reach the carburetor.

Protecting External Outboard Components

  1. Lubricate all outboard components, lubrication points, and drive shaft splines.

  2. Touch up any paint nicks.

  3. Spray Quicksilver Corrosion Guard on external metal surfaces (except corrosion control anodes).

Gear Case

  1. Drain and refill the gear case lubricant.

Positioning Outboard For Storage

Store outboard in an upright (vertical) position to allow water to drain out of outboard.

If outboard is stored tilted up in freezing temperatures, trapped cooling water or rain water that may have entered the propeller exhaust outlet in the gear case could freeze and cause damage to the outboard.

Battery Storage

  1. Follow the battery manufacturer's instructions for storage and recharging.

  2. Remove the battery from the boat and check water level. Recharge if necessary.

  3. Store the battery in a cool, dry place.

  4. Periodically check the water level and recharge the battery during storage.

MYP4F10R - Mercury 4-Cylinder 4-Stroke 40-115HP 1999-2014
ME-G4-15-N - Mercury/Mariner 4-Cylinder 4-Stroke 150HP 2011-2015
MYP6F20R - Mercury/Mariner V6 4-Stroke 225HP 2004-Current
802878Q55 - Mercury Marine CORROS GUARD
8M0058681 - Mercury Marine QUICKLEN32OZ

Share on social: