As winter begins to make way for the grass growing season, where the days begin to get warmer and brighter, it’s time to think about lawn care! Soon enough, it’ll be time to rev up your John Deere mower and get to work! However, after sitting dormant for these past few winter months, you may want to consider performing some maintenance on your lawn tractor or zero-turn mower to keep it running in tip top shape over the warm months to come. (Not a do-it-yourselfer? Click here to schedule a service appointment at any of our local Valley Truck & Tractor locations and we can get the job done for you!)


Battery inspection and health check

Before the winter months arrive, it is wise to disconnect the battery from the mower, and to store your mower’s battery in a cool, dry place to protect the battery/battery acid from the elements and possible electrical draining. While the battery is not in use for an extended period of time, check the battery charge from time to time throughout the winter. If it is below 50% charge (or below 12 volts DC), use a battery tender to bring the charge up to 100%. Make sure to fully charge the battery each time. If you use a car-style battery charger, it is best to use the lowest amp output available (usually 2 amps).


If you did not properly store your battery, there are several steps you can take in order to check if you need to replace it. First, put on a pair of safety glasses and gloves as the battery may require removal for proper inspection, then inspect for any cracks or bulging sides of the plastic battery body, or corroded terminals (usually green or white colored buildup) on and around the battery. If any corrosion is visible, remove the battery cables by removing the negative cable first, then the positive cable, and clean all visible corrosion off with baking soda dissolved in water, and a small wire brush. If cracks or bulging are present, battery replacement is required. If there are no cracks, bulging, or corrosion, you can then test the battery condition as noted above, or attempt to charge the battery (also noted above). In most cases, the battery is of the type that does not require inspection of the electrolyte level as they are sealed from the factory. If you do have removable caps for electrolyte level inspection, and the levels are low, fill the battery cells with DISTILLED WATER ONLY. When possible, avoid removing battery caps. You can also bring it to one of your local Valley Truck & Tractor locations for proper battery inspection and care. In addition, if you did not occasionally charge the battery over the winter months, there is a chance it won’t hold a charge, and you’ll be required to purchase a new battery. Please contact us at Valley Truck & Tractor and let us know which model mower you have to get a battery quote.

Once you have a fully charged, undamaged battery, go ahead and reinstall it into your mower. 


Remove and inspect the Spark Plug(s)

The next step to performing maintenance on your lawn mower is to remove the spark plug. This is to check the general condition of your spark plug(s). You’ll need a torque wrench with a spark plug socket, as well as a spark plug gap tool. Park the mower in a safe location on a flat surface, with the engine off, parking brake set, and the keys out of the ignition. You will then need to remove the spark plug cap from each plug, and insert the spark plug socket and turn counter-clockwise to loosen, then remove the spark plug. When inspecting the spark plug, you are looking to see if the porcelain in the center of the plug is white, brown/yellow, or black, and to see if there is rust on the metal electrodes. Black and rusty plugs will require replacement. If the plugs look to be in good shape, inspect the gap between the center electrode of the plug and the bent wire protruding from the edge of the threaded portion. Use the tool to bend the outer electrode to the correct size. The size will vary depending on your mower, so use your mower’s operator manual to determine the correct gap. You can use carburetor cleaner fluid in order to clean the plug(s) if they appear to be in good condition, just to assure there is no build-up on the tip before reinstallation. Set aside to let dry before reinstallation. Torque the plug to the specification in the manual during installation.


Replace the Spark Plug(s)

Replace the spark plug and torque to the proper specifications outlined in your mower’s operating manual. Then, reattach the spark plug cap(s) and you can start your mower. Please refer to your operating manual for spark plug type as there are several different engines offered throughout the S and E series line of mowers. This information can also be provided by a visit, or phone call to any of your local Valley Truck & Tractor locations. If possible, be prepared with the mower’s Product Identification Number to aid in getting the correct parts.


Gasoline Maintenance

During wet winter months, moisture may accumulate in your mower’s gas tank, especially if it is stored outside and/or uncovered. Generally, gasoline also goes bad after about a month, and if left longer than that, the gasoline will break down and leave deposits that start to solidify in the carburetor, plugging any orifice inside, as well as corroding the carburetor itself. These deposits along with the break-down of the fuel will also damage any rubber components in the fuel system (think fuel pump, carb float valve tip, hoses, gaskets). To prevent this, drain the old gasoline from the fuel tank and the carburetor before the start of the winter season. Another option that may work better for some owners, would be to start and run the mower for a minimum of 2 minutes on a weekly basis. The added benefit to running the mower is it allows the battery to get a bit of a charge, and it keeps all the engine internals lubricated. If you can operate the mower and all of it’s functions on a weekly basis, this would be even better! 


If the gasoline was not drained from the fuel tank and carburetor, the first recommendation is to drain the fuel out of both the fuel tank, and the carburetor before starting the engine. This will allow you to visibly see the condition of the fuel, and give the fuel system the best chance to operate as close to “properly” as possible. Bad fuel is typically a dark yellow/brownish color and has a pungent smell. If the fuel has already broken down, you may see green goo built up where the gasoline had pooled, and it will smell very similar to paint varnish. If your mower’s fuel system has reached this point, call one of your local Valley Truck & Tractor service departments to get a rough estimate on cost for repairs. This task can be quite labor intensive and possibly require special tools. It is NOT recommended to run any fuel system cleaning chemicals in any John Deere lawn mower. These chemicals have been found to attack rubber parts, potentially creating a fuel system issue beyond that of what damage bad gasoline may have already done. It IS recommended however, to use a fuel stabilizer that is formulated specifically for California gasoline. Fuel stabilizer can allow the fuel to be useable, and prevent break-down of the gasoline, for up to 3 months, depending on the grade of fuel and how it is stored. Your local Valley Truck & Tractor has John Deere fuel stabilizer in stock, and if needed, most auto parts stores have a California gasoline formulated fuel stabilizer. Just add the fuel stabilizer to fuel inside a can, shake the fuel to get a good mixture, then add to the fuel in the mower’s fuel tank. A general rule of thumb is, if you know you will not be running your mower for any longer than 2 weeks, add fuel stabilizer to the system, or drain the fuel. If you added fuel stabilizer, you can then run your mower until the mixture reaches the carburetor, therefore helping to prevent fuel system issues before they get expensive.


Perform general service to engine

All John Deere S series and E series mowers have pre-packaged Maintenance Kits available at an affordable price. These Maintenance Kits have all required components needed to service the engine of your John Deere mower. Armed together with the mowers operator manual, these Maintenance Kits provide a simple, yet effective means for giving your mower’s engine the attention it needs. All kits are from John Deere, for your John Deere mower, and supply the correct number of spark plugs, an air filter, a new Quick Change oil filter (for those models that are equipped as such), the proper engine oil and oil filter with the correct number of oil bottles required for a regular style oil change, a fuel filter, and in some cases, a reminder sticker for you to input the date and hours at time of engine service to log your accomplishment. For this convenience, all you need to do is call or stop by your local Valley Truck & Tractor dealer armed with your specific model, or Product Identification Number to obtain the correct kit for your mower. 

If this kit does not appeal to you, no problem. Your local Valley Truck & Tractor will be able to supply you with any part you would like to specify to have.


John Deere Easy Change 30 Second Oil Change System

The next recommended step is to perform an oil change on your mower. This step couldn’t be easier, thanks to the John Deere Easy Change 30 second oil change system. Many S100 series lawn tractors include this feature (S120, S130, S160, S170, S180), as well as some older E100 series mowers (E120, E130, E150, E160, E170, E180). You can check out the system and how it works by visiting

If your mower does not have the Easy Change System, refer to the next segment.


Regular Oil Change

If your mower does not have the Easy Change feature, perform a routine oil change. If you are performing a routine oil change, make sure to check your mowers manual for oil specifications and capacities. An engine oil change is recommended to be performed before the winter storage season. When used oil sits in an engine, it can become acidic. This acidic oil can and will corrode some engine bearings and gaskets. Begin by parking your mower on a flat, level surface. For easier drainage, let the mower run for about 2-3 minutes. Then shut it off, and let it sit for another 2-3 minutes. The oil change process is outlined in your mower’s operator manual. Be sure to torque the drain bolt to proper specification as outlined in the mower’s operator manual when reinstalling. Though it is not required, it is also recommended to use a new drain bolt gasket with every oil change. All John Deere S series and E series mowers also have oil filters. It is recommended to replace the oil filter a minimum of every other oil change, if not at every oil change. If you choose to replace the oil filter, remove it with an oil filter wrench. The oil filter wrench will be available at your local Valley Truck & Tractor location, and at most auto part stores. Some oil may spill upon removal of the oil filter, so be prepared with some rags or paper towels. With a clean rag and maybe a little contact cleaner, clean the oil filter sealing surface on the engine (the aluminum surface), and the area around where the oil filter mounts. We have seen the old oil filter gasket stick to the sealing surface of the engine. This will cause a serious oil leak if left stuck to the engine with the new oil filter installed on top of it. If the old oil filter gasket is found to be stuck to the engine, remove the gasket and clean the sealing area as noted above. The new oil filter’s gasket should also be coated with a thin application of oil, and then screwed back onto the engine and torqued to spec as outlined in the mower’s operator manual. Avoid tightening the oil filter by hand as more often than not, it is not enough torque to keep it on the engine. Take care not to over tighten either. Once more, be sure to use the correct amount and type of oil that is specified in your mower’s operator manual. Insert the dipstick, and make sure the oil is reaching the full mark on the dipstick. Once the oil level has been verified at proper level, and there are no leaks, fire up the engine and let it run at slow idle (turtle, or full bottom position) for 1-2 minutes. Then shut off the engine and allow it to sit for 3-5 minutes to allow the oil level to stabilize. Remove the dipstick and clean it off. Install the dipstick into the engine but do not tighten down. When you remove the dipstick, once again verify that the oil level is set to the upper level marker. Add oil if needed. Reinstall the dipstick once more, and tighten. Check for any oil leaks around the drain and oil filter. Last, wash areas where oil was spilled with soap and a water hose. It is not recommended to use a pressure washer for this task, as damage can occur. For regular oil level checks, the engine must be cold, before starting the engine, and on level ground.


Air Filter maintenance/inspection

The next step to address is the air filter. First, remove the air box lid/air filter cover, then inspect for critter intrusion, over all air filter visual condition, and for proper installation. If the paper air filter is worn, torn, or covered in oil, replacing it with a brand new filter is the best option. In most cases though, paper air filters can be cleaned, to an extent, by blowing air from the inside out at very low pressure. High pressure can damage the paper air filter. If your mower’s air filter is a paper filter, and has been in the mower for more than 6 months without use, it is recommended to replace it with a new filter. The reason for replacement is that paper filters are susceptible to water, oil, and even the air itself! If they sit for too long, they can dry out to the point of deterioration, or the moisture in the air can degrade the paper element. If your mower’s filter is reusable foam (older model mowers), you may clean it with water and an air filter cleaning detergent. Once clean, use a specific foam air filter oil, or at the very least, a heavy weight gear oil. After oiling the filter by repeatedly squeezing the oil into the filter with your gloved hands, the filter should not drip, and will not feel oily, but instead it will feel tacky to the touch. If there is a foam filter covering your paper air filter, DO NOT oil the foam filter cover. Install this foam cover dry. If you are having troubles locating, removing or replacing your air filter, check your mower’s operator manual for guidance.


Undercarriage Maintenance

While the mower is not going to be in use for a while, it is a perfect time to clean the undercarriage of your mower. The first thing required will be to either lift the front of the mower to access the blade area, or to remove the deck from the mower. Deck removal is outlined in the mower’s operating manual. If you choose to remove the deck, it is a good idea to take pictures of all the details of the mower and deck with your phone, such as belt routing, bolt placement, and hanger locations/adjustments. This will greatly aid in getting things back to the way they were, and save a lot of time! The most common place requiring regular cleaning is the top of the mower deck. Grass clippings regularly blow up and onto the top of the deck and build up around the deck spindles, where the belts route. Regular maintenance typically calls for nothing more than using a leaf blower to remove the build-up from the top of the deck. You can also use a hose in order to loosen any clippings, dirt, or debris from the undercarriage. Though a pressure washer can be used, make sure to closely pay attention to where the spray from the nozzle is going. Pressure washers can, and will, force water into gaskets, grease zerks, bearings, and can easily remove decals. Use caution when using a pressure washer. As for the underside of the deck, where the blades are, wet grass likes to build up and dry in multiple places. This will decrease the efficiency of the cutting ability of the deck. Usually an old screw driver, along with a hose will be required to get the concrete-like build-up removed. A pressure washer is also very effective for cleaning around the blades. The best option is to use soap and hot water. Wearing safety gloves, take a sponge or brush and carefully clean the undercarriage. Rinse and repeat as needed. After the final rinse, dry your mower off. Again, your trusty leaf blower comes in handy for this task. Lastly, using waterproof grease in a grease gun, grease all zerk fittings on the mower and mower deck. All zerk fittings are called out in the mower’s operating manual. Wipe off any excess grease with a clean rag or paper towel.


Mower Blades

The last step to getting your mower running at maximum performance is sharpening the mower blades. This is best done by a professional, and our service team at Valley Truck & Tractor would be happy to assist you! It may also be time to replace them altogether, or upgrade from the standard blade setup to a mulching blade kit!


Mower tire condition and pressures

One thing that is largely overlooked on ALL mowers, are the tires. Tires are a very reliable item that in most cases require little maintenance. Unfortunately, due to this reasoning, tires are one of the most neglected service items on mowers. When the tires are filled to proper pressure, they then begin to lose a very small percentage of the air volume in the tire through the rubber and sealing surfaces over time. The larger the tire, the longer it takes to lose air volume (and pressure, as they are tied together in this case). Smaller tires in the same timeframe will appear to have lost more air due to less volume inside the tire at the same percentage loss rate. Aside from regular tire pressure checks throughout the mower’s use, the tire pressures need to be checked and adjusted after sitting for the winter storage period. Another thing to consider with the tires is the condition of the rubber. Over time the tires will slowly develop cracks in the surface of the rubber. Just by being in the atmosphere, tire rubber will degrade over time. It is a good idea to inspect for these cracks as they can grow larger and become more than a nuisance quite quickly. Lastly, it is a good idea to inspect the tires for anything that has punctured them. Some of you may be aware of “goat heads”, as they are the number one cause of punctures. Coming in at a close second, are “star thistles”. Addressing these punctures before using your mower can prevent many future headaches. If these types of punctures are a regular occurrence, you might want to think about using a tire sealant. There are some good, and some bad tire sealants out there, so there is no rule of thumb when picking a reliable tire sealant. Your local Valley Truck & Tractor can direct you to some good tire sealant suggestions.


Park brake operation

Last on the list of inspections for the new season of mowing is the park brake. The park brake, aka emergency brake, is important to both operation of the mower, and safety. If the park brake will not operate properly by foot, the mower may not start as there is a safety switch that it operates for starting purposes. If the orange park brake lock lever does not hold the park brake pedal in place, the mower could possibly roll on the operator. This is a safety issue. One thing to remember with the park/emergency brake, is that it is NOT a regular brake! It was not intended, nor designed to be used as a regular brake to stop the mower on all occasions. When the park brake pedal is pushed in, this action not only operates a brake to hold the mower in place, it also releases tension on the v-belt that connects the engine pulley to the drive pulley that operates the transmission. It is very common to find the “traction drive belt” derailed off the pulleys due to operating the park brake as a regular brake for regular stopping. The mower direction pedals, when released, offer all the braking required for most situations. Therefore, it is a good idea to always check for proper operation of the park brake system.


Now that you’ve performed maintenance on your John Deere mower, it is ready to take on any of your grass cutting needs. After all, nothing runs like a Deere!


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