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How-To Spring Commission
A Marine Engine

a tool boxPhoto courtesy Jensen Tools/

Spring Commissioning Continued - (Part 2)

Before you install the propeller, inspect its blades for nicks and dings. Otherwise the wheel will vibrate and cause premature wear to shafts and bearings. Straighten dings with a rawhide mallet. Minor nicks (smaller than your thumbnail) can be filed smooth. Remove as little metal as possible to prevent unbalancing the wheel. Examine the propeller's shock-absorber bushing for cracks or otherwise obvious damage.

Coat the propeller shaft with corrosion fighting, marine grade grease, and then re-install the propeller using a new cotter pin. Check water intake and discharge ports for obstructions.

Examine the sacrificial zincs noting they should be replaced before they've corroded away to less than half their original size. Regardless of whether or not an individual zinc needs replacing, remove it and make sure there's good metal to metal contact between the zinc and its mating surface. Otherwise it won't work its magic. Before replacing, coat the bolt's threads with anti-corrosion grease.

Inspect the power head for loose, missing or damaged parts. Lay a wrench on every bolt, including engine mounts and manifold bolts, making sure none have vibrated loose. Don't forget the steering linkage! Tighten as necessary, but do not over-tighten. On outboards, be sure to check the hold down bolts that secure the motor to the transom. Tip: An outboard motor's loose and dangling hood rubber can be glued back in place with weatherstrip compound.

Last fall during lay-up, you wisely loosened the alternator and water pump drive belts. Before snugging them up again, first inspect for cracks, checkering or frayed edges. Replace as necessary. Correct tension allows for about 1/4 to 3/8 inch play measured midway between the pulleys.

Similarly, visually inspect cooling system hoses. Checkered or cracked surfaces indicate replacement is necessary. Firmly grab each hose. Any that have lost resiliency and become hard and brittle, or are have bulged require replacement. Also check the hose clamps replacing any that have corroded or been otherwise damaged. Lay a screw driver on each one making sure vibration hasn't loosened them.

Last fall you mothballed the motor by fogging its cylinders with a sticky, preservative oil that resists sliding off the cylinder wall's polished surfaces. Come spring, this oil must be blown out of the combustion chambers. To do so, remove all of the spark plugs. Throw the throttle lever wide open. Crank the engine for about a minute, staying clear of the oil vapor that blows out through the spark plug holes.

Hint: Before cranking the engine, open the fuel line valve so that cranking the engine not only clears the fogging oil, but also pre-lubricates bearings and fills the carburetor float bowl. - Continued - (Part 3)