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Winter Sabbatical

Originally Published in MotorHome Magazine

The fall season can be exhilarating, with leaves that have turned red or golden, air that
is so crisp you can taste it and weather that can change from Indian summer days to snow
flurries within a few hours. After one last trip through the colors, it may be time for
motorhome hibernation. If your plan is to store your coach rather than travel periodically
through the winter months, thorough winter prep is essential because certain items, if
ignored, can result in expensive repairs. At the top of the list is prevention of frozen
water lines. If you’ve ever had a serious freeze you know how expensive ruptured pipes can
be – especially difficult if lines or joints burst in inaccessible areas. Heating a coach
to prevent freezing can be risky without daily monitoring, even for relatively short
periods and even if you’re certain of how much heat is necessary, and where. Electrical
circuits may shut down unexpectedly, and a motorhome furnace may quit due to a blown fuse
or another cause – such as one case (true) in which a mouse got into the furnace blower,
unbalanced it and the fuse blew, resulting in no heat. Anyone who has had a freeze vows to
make sure it doesn’t happen again. Of course, there’s more to winterization than water
systems, so let’s get started.


Bug splatters, road tar, carpet
soils, refrigerator grime … all are more difficult to clean after sitting through a winter,
so a thorough cleaning is in order, inside and out. Check awnings for mildew. Consider
waxing the exterior, especially if it is not painted, to retard deterioration of plastic
decals and fiberglass gelcoat.

Chassis Preparations

  • Oil change, chassis lubrication
  • Coolant change
  • Hydraulic jacks
  • Tires, batteries, fuel

Before you tackle the water system, chassis service is in order if more than 3,000 miles
have elapsed since the last service. Engine oil accumulates contaminants that produce
acids. When left to sit for several months in storage, acids in dirty oil can attack
bearings and other parts. Check transmission and rear-axle lube levels, lubricate chassis
components with grease fittings and perform any other regular maintenance such as an engine
coolant change that is called for in the owners manual. Fuel tanks containing gasoline
should be topped off after adding a fuel preservative such as Sta-bil in amounts
recommended on the additive container. Diesel tanks should be topped off after adding a
microbiocide. Low-sulfur diesel fuel is particularly vulnerable to water contamination,
which can sponsor an invasion of microorganisms. In severe cases they can cause fuel filter
plugging and clogged injectors. Windshield washer fluid should be replenished for the
anticipated low temperatures. Clean the rams of hydraulic jacks and lube them with silicone
spray or the compound recommended by the system manufacturer – especially important if the
coach is to be stored with jacks extended. Also check the level of hydraulic fluid in the
reservoir. Tires should be inflated to recommended pressures for travel, and it is best to
park on plastic rather than pavement or dirt – to help prevent deterioration. They should
be covered unless the coach is stored indoors. Batteries should be fully charged before
storage, and they should be disconnected from the chassis to avoid gradual depletion by the
power drain from radios and other equipment that draws tiny amounts of power even when
turned off. Battery electrolyte should be checked (except sealed batteries), and batteries
should be recharged at least every two months – or more often in extremely cold weather.
You can also use a battery maintenance charger – such as a Battery Tender – to safely keep
the coach batteries up to charge. If recharge is not practical while batteries are in the
motorhome, they should be removed to a location where it is possible – preferably one that
is kept above freezing.

Freshwater and Waste Systems

  • Drain water lines and tank
  • Drain water heater and bypass water pipe
  • Drain and flush holding tanks
  • Protect P-traps, tank valves

In most coaches, the water system is fitted with a water heater bypass system that allows
pumping of RV antifreeze into the lines without having to fill the water heater, which
should be drained. A blow-out plug can be inserted into the city water inlet to use air
pressure for clearing the lines, but it’s not a guarantee of clearing all water. After the
water tank, lines (using low-point drains) and water heater are drained, turn the water
heater bypass valve to the bypass position and close all low-point drains. Use your
antifreeze intake hose (usually connected to a T fitting in the line between water pump and
tank) to pump non-toxic RV antifreeze through all lines, turn on one faucet at a time until
the pink stuff flows from each, and don’t forget the shower heads inside and outside,
refrigerator icemaker and washer, if so equipped. A pump diverter kit (merely a T valve and
a length of hose) is available from RV suppliers. The holding tanks should be filled,
dumped, refilled and flushed. For the waste tank, use either a tank flush hose fitting
(which is provided on many coaches), or, if not so equipped, a spray wand inserted into the
tank via the toilet. Pour a few ounces of RV antifreeze into all drains, and into the waste
tank through the toilet to ensure freeze protection for P-traps and for tank valves.

Other Systems, Precautions

  • Refrigerator
  • Furnace
  • Slideouts
  • LP-gas
  • Roof, awnings
  • Mice, insects

With all power sources turned off, the refrigerator should be clean and dry before storage;
prop the door open slightly. The exterior furnace openings should be covered to keep out
insects, and a commercial rodent repellent may be placed near the refrigerator gas jet to
help prevent insect nests (other areas, too). Mice love to nest in motorhomes, and you’ll
need to make sure all crevices and access points are well sealed. Recheck the coach once a
month to look for infestations. Seals on compartment doors and slideouts may be coated with
whatever the motorhome manufacturer recommends, such as petroleum distillate-free
protectant, and the slideout mechanism should be lubed if recommended by the manufacturer
(commercial products, like the one from Protect All, are available for this task). The
LP-gas system requires nothing more than turning off the valve at the tank. Awnings must be
dry before storing. Check the roof closely for cracks in sealant around vents and seams. If
the coach is to be stored outside, consider a full cover, which will help prevent
deterioration of decals and fiberglass gelcoat. It’s less important with full-body paint,
but helpful in preserving the surface. The cover should be of breathable fabric, not
plastic that will trap moisture in the coach. Do not use blue tarps commonly sold at
hardware and discount stores.


When it’s time to think of
getting back on the road, the coach will be clean and ready after reversing a few
winterizing procedures. To remove the antifreeze from water lines, fill the water tank and
use the onboard pump to clear each water line of antifreeze by opening each faucet, hot and
cold, one at a time until the water runs clear. Check tire pressures, make sure batteries
are up, turn on LP-gas and test-run all appliances. Check for any signs of water leakage
through the roof. If everything checks out, you’re set for the next round of great
motorhome adventures.

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