Prepare Your Outboard for Boating Season in 6 Steps

Yes, you’ve been itching to get your boat out of storage and ready for a new boating season, and we’re as excited as you are! But wait, not so fast. Is your outboard motor ready to get back in the water?  

Outboard boating season preparation steps

Hopefully you winterized your outboard before putting it into storage, in which case your pre-season preparations will be easy. However, if you didn't winterize it, you'll have a little extra work to do.

We’ve already published a plethora of extensively detailed articles here at the blog about winterizing and de-winterizing an outboard, so here’s a quick breakdown for preparing your outboard for a new boating season in 6 easy steps.

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Step #1 - Powerhead

Remove the top cowling and inspect the powerhead for critter nests, and remove any you find. If you sprayed the powerhead with corrosion guard when you winterized it, chances are dust and dirt have built up on it, which you should now clean off. Inspect the intakes and exhausts for critters and debris, and clean them out as needed. If you sealed off the intakes and exhausts with shop towels or rags during winterization, remove them now.

Step #2 - Hoses and Wiring

Check all hoses for splits or cracks, and for areas where a hose has become hard and brittle. Inspect the wiring for damaged or worn insulation, and check for rodent damage. Replace any worn or damaged hoses and wires as needed. Make sure all the hose clamps are tight and leak-free, and check that all the electrical connectors are secure.

Outboard spring boating preparation

Step #3 - Spark Plugs

If you sprayed the cylinders with fogging oil as part of the winterization process, remove the spark plugs and clean off any oily residue from them. After your first day back on the water, remove the spark plugs again and clean any last traces of burned fogging oil, or better still, replace the spark plugs with new ones. Even if you didn’t protect your outboard with fogging oil, you should still remove the spark plugs and clean or replace them.

Outboard boating season preparation spark plugs

NOTE: If you used fogging oil to winterize your outboard, it will burn away and generate smoke from the exhaust the first time you run the motor. This is normal and nothing to worry about.

Step #4 - Oil and Fuel

You should have changed the engine oil and gearcase lube as part of the winterization process. If you did, you’re good to go as far as lubricants are concerned. However, if you didn’t change the oils, drain and replace them now. Oil breaks down over time and any old oil sitting stagnant in your outboard for months won’t provide adequate lubrication when you start running it again.

Outboard spring boating preparation oil change

If you filled the gas tank to the brim to prevent condensation forming inside it, and treated the fuel with stabilizer before storing the outboard, you don’t need to take any further action with the fuel system. However, if the gas tank was left half empty and the fuel left untreated, drain the tank and dispose of the stale fuel, then allow any moisture within the tank to evaporate before filling it up with fresh, stabilized fuel.

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Step #5 - Battery

If you removed the battery during winterization and kept it connected to a battery tender during storage, all you need to do now is clean the terminals and reinstall the battery. However, if you didn’t maintain the battery during storage, it’ll likely be dead. You can try recharging it, but a battery left idle for so long usually won’t be able to hold a charge and must be replaced. 

Step #6 - Engine Flush

Assuming you flushed the engine before winter storage, you don’t need to flush it again, but it doesn’t hurt. Of course if you didn’t flush your outboard before storage, do it now to make sure there’s nothing inside the cooling system preventing the flow of water. When flushing an outboard, make sure it’s in the vertical position, then attach engine flushers and flush it for at least five minutes.

That was just a quick breakdown of the basics of preparing an outboard for the next boating season. Watch the video above for a universal walkthrough on how to de-winterize outboard engines




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