Quicksilver Blog

Preseason Outboard Prep

Spring has arrived and we’re all eager to get on the water, but before you splash your boat, it’s smart to take some time to tend to a short preseason outboard engine maintenance checklist

By giving your engine a little attention now you’ll ensure a trouble-free season and add to the lifespan of your outboard. These are general recommendations for most outboards. Always reference your owner’s manual for the maintenance schedule and specific instructions for your model.

Things You Should Have Done Already

If you put your boat up correctly for offseason storage, you’ve already taken care of these items. If you just parked your boat last fall, start here:

Change the oil and filter: Four-stroke outboards should get an oil-and-filter change before long-term storage or at 100 hours. If you didn’t change your oil and filter last fall, do it now. The line of premium Quicksilver Marine Lubricants includes four-stroke engine oil for any outboard brand, specifically formulated for the unique needs of the marine environment. In this video, pro angler Scott Glorvigen of Wired2Fish gives a great tutorial on the oil change process.

If you did change the oil last fall, good job! But check the level before you start the engine for the first time this spring.

If you have a two-stroke outboard, fill the reservoir (if so equipped) with fresh injector oil before the start of the season. Quicksilver two-stroke oil products exceed industry standards and meet or exceed all outboard manufacturers’ warranty requirements.

Change the gearcase lube: It’s a good idea to change the gear lube in all outboards annually, and the best time to do it is before off-season storage. If there’s any water in the gear lube it could freeze and crack the case in very cold climates. That moisture can also cause corrosion on gears and bearings and shorten gearcase life. If you neglected your gearcase lube last fall, change it now before the new season starts. In this how-to video, Glorvigen demonstrates how to change the gearcase lube using premium Quicksilver gear lube, an easy task for most boat owners.

If you did change your gear lube before storing the boat, check for a puddle of lube on the floor beneath the outboard. If there’s a leak, you could have a bad prop-shaft seal, or the drain screw was not tightened correctly.

Prep the Fuel System

Most outboards have a small fuel filter, and it’s good preventative maintenance to change the filter annually. In this video, Glorvigen shows how it’s done on a Mercury 150hp FourStroke outboard. If your boat has an onboard water-separating fuel filter, also change out that filter element for a fresh one, and while you’re at your service center, consider buying an extra filter to keep on the boat as a spare for the day the filter is contaminated with water. Quicksilver fuel filters are available for many outboard models.

If you treated the gas in your boat’s built-in fuel tank with a quality fuel stabilizer before off-season storage, you should be able to start the season with that fuel. If the tank is less than full, top it off with fresh gas, and if possible avoid E10 (10 percent ethanol) gas, which can attract water and cause maintenance headaches in the marine environment. If you didn’t treat your gas before storage, consider draining as much as possible from the tank and starting with fresh fuel. If this is a large quantity of gas, some marine service centers can drain and dispose of old fuel for a fee. Gas that’s gone “stale" can leave deposits in filters and the engine, and can cause the motor to run poorly.

With this first tank of fresh fuel, the use of quality fuel additives like the Quicksilver Fuel Care System can help avoid fuel-related engine problems during the entire season. Quicksilver fuel additives are specially formulated to keep modern fuel optimized, protect the fuel system, remove harmful deposits and help any marine engine run its best.

Here’s how the system works:

  1. Quicksilver Quickare additive should be used at every fuel fill-up to help control fuel tank moisture, gumming and corrosion.
  2. Use Quicksliver Quickleen every few fill-ups to reduce carbon buildup and extend spark plug life.
  3. At the end of each season, Quicksilver Quickstor will stabilize fuel and keep internal parts lubricated.

Battery Care

Your outboard needs a reliable battery to deliver easy starts all season. When properly maintained, a marine battery may last from five to seven seasons. If your battery is five or more years old, a qualified service center or even many auto parts stores can perform a load test to gauge its health and determine whether it should be replaced before it’s too weak to start the outboard. If the battery has seen more than five seasons, simply replacing it is good insurance, and beats having a dead battery ruin a day on the water.

Boat batteries should be secured with a battery box, a battery strap or a battery bracket so that they don’t get tossed around in rough water, which can shorten battery life. During the season check to make sure the battery is secure and the terminals are tight. Replacing the wing nuts often found on boat battery terminals with self-locking (Nyloc) nuts is a good way to make sure those connections stay tight.

A Few Other Details

Follow the service schedule in your outboard owner’s manual for guidance on other maintenance points. Here are a few that apply to many outboards.

Belts: Some outboards have a timing belt, or they might have a belt to drive the alternator or an air-injection pump. These belts generally have a long life, but it’s good to inspect them for wear preseason. Replacing the belt might require a special tool, but it’s a quick job for an authorized service center. Quicksilver offers a complete line of belts for most marine engines.