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Proper Engine Winterization Ensures Reliability Come Spring
By Brad Murphy
Vice-President and COO, Subaru Industrial Power Products
Many of us have already started to
prepare for winter. We bundle up with heavier gear to ensure our bodies stay
protected and warm against winter’s chill. But we aren’t the only ones that
need protection against nature’s harsher elements.
For many contractors, whether residential
building or commercial construction, landscape or utility, equipment is often
used very little during the winter season – and in some areas of the country,
not at all. If a piece of equipment will sit idle 30 days or more, it’s necessary
to winterize the engine. Four primary areas must be addressed.
Clean and Inspect
The first step in preparing an
engine for winter storage is to give both the engine and machine it’s powering
a good cleaning. Shut down the engine and allow ample cooling time, then simply
wipe the entire unit clean with a towel, removing any leaves, grass or other
debris. An air compressor may be used to help dislodge any particles that can’t
be reached by hand.
filter should also be cleaned, or changed if necessary. A paper air filter
should always be changed prior to winterization. However, a foam filter can be
cleaned if it’s relatively new. Use hot soapy water and let the filter drip dry
before putting about one ounce of oil on it. Squeeze the filter to saturate,
then blot with a paper towel before reinstalling.
One of the primary reasons engines
must be winterized if idle for more than 30 days is because that’s the point
when fuel begins to go stale, making fuel the next item to address for proper
winterization. Stale fuel leads to residue build-up, which can plug the small
fuel jets in the carburetor and cause major headaches – and costly repairs.
There are two primary methods to address this problem.
The best approach is to drain all the
fuel out of the gas tank, then start the engine and run for a few minutes to ensure
the fuel lines and carburetor are free. This option eliminates any potential
issues with stale fuel down the road.
Another acceptable approach is to
fill the tank full, then add fuel stabilizer. Especially in extremely cold
climates, a half-full tank leaves room for condensation build-up. This can
quickly cause rust to form inside the tank, so it’s important to ensure the
tank is completely full. However, it’s only wise to go this route if the engine
has a fuel shut-off valve. Upon filling the tank, shut off the valve and run
the engine until it dies. This ensures the carburetor is dry and leaves no
chance for moisture accumulation.
In day-to-day operations, changing
the oil is considered a routine part of a maintenance program. When it comes to
winterization, the same rules apply. Oil becomes contaminated from normal
engine combustion during operation. Acid builds and if left to sit over the
winter, may cause corrosion. The same is true of water and other particles that
can contaminate oil during typical operation. Also, oil that sits for too long
can become thick and gummy, preventing a smooth start come spring. Be sure the
engine has fresh oil before storing the equipment.
Because colder temperatures may
still be present when it’s time to start up the equipment in the spring, it’s
also a good idea to adjust viscosity at this time. Multi-viscosity oil is a great
option, especially in areas with unpredictable or harsh temperatures. It
recognizes outdoor temperature and adjusts to proper viscosity.
Spark Plug Check
Finally, it’s important to replace
spark plugs prior to winterization, as dirty or damaged ones can cause a
decrease in power and lead to poor starting performance come spring. Remove the existing spark plugs,
then put a teaspoon of oil into the plug. Pull the recoil over a few times
until resistance reaches its maximum. It’s at this point, top dead center, that
both the intake and exhaust valves are closed, leaving no room for moisture,
debris – or even a pest – to get inside. It also provides the dual benefit of
distributing the oil across the head, rings and valves, and preventing moisture
and rust in the combustion chamber. Upon replacing with a new spark plug, set
the gap as instructed in the owner’s manual, and replace.
Spending just a few minutes to
winterize an engine may save a lot of time and frustration in the future by
better ensuring dependable operation come spring.