Once the sealcoating season winds down and winter temperatures settle in, contractors face a critical window for equipment care. The machines that performed reliably all summer need attention before they sit idle for months. Neglecting sealer applicator maintenance during winter downtime leads to costly repairs, clogged systems, and delayed start-ups when spring arrives. Proper off-season care — including thorough cleaning, pump disassembly, and system flushing — protects your investment and ensures your rig is ready to work when the weather turns. For a broader look at cold-weather equipment practices, see Cold Weather Tools Care Operation Winter.
Why Winter Maintenance Matters for Sealer Applicators
Sealer applicators endure harsh conditions during the working season. They handle abrasive materials, operate under pressure, and accumulate layers of dried sealer on every surface. When a machine is parked for winter without proper care, several problems develop:
- Sealer residue hardens inside the tank, agitator shaft, and blades, forming a clay-like buildup that can jam the agitator or clog the filter basket when the machine is restarted.
- Moisture trapped in the pump and plumbing lines freezes. Sealer that freezes inside pipes crystallizes into a consistency thicker than peanut butter, requiring every plumbing piece to be taken apart and cleaned by hand.
- Sand left in the pump system scratches internal components, accelerating wear on leathers and valves.
- Hidden problems such as worn bushings, cracked brackets, leaking hydraulics, and chafed hoses remain undetected under layers of sealer and debris.
Gordon Rayner, president of Rayner Equipment Systems, puts it simply: cleaning and inspection is the single most important thing a contractor can do. Dirty equipment hides problems that need attention. He recommends approaching equipment care the way a pilot inspects an aircraft — a contractor is betting their business on its performance.
The goal is to eliminate downtime. Every hour spent repairing preventable damage in spring is an hour of lost production during the prime sealcoating window. A well-maintained machine starts the season ready to work.
Step-by-Step Sealer Applicator Winterization Process
Winterizing a sealer applicator follows a logical sequence. Each step builds on the previous one, and skipping any step can leave the equipment vulnerable. The complete process can be broken down into four stages: exterior cleaning and inspection, tank cleaning, pump and plumbing protection, and final antifreeze treatment.
Exterior Cleaning and Full Inspection
Start by thoroughly cleaning the outside of the equipment. Scrape off dried sealer from every surface, including the frame, tank exterior, wand assembly, and spray bar. This step is not about appearances alone — removing the buildup allows you to see what you are working with.
Once the machine is clean, perform a detailed inspection and document your findings in writing. Look for:
- Worn bushings and bearings
- Loose or broken chains
- Cracked mounting brackets
- Hydraulic fluid leaks around fittings and hoses
- Chafed or abraded hoses that could fail under pressure
- Corrosion on electrical connections and control panels
- Worn spray tips and nozzle patterns
Make all necessary repairs before storage. If you notice a problem that seems to recur every season, Rayner suggests finding a way to improve the system so it does not happen again. SealMaster’s Mike Bechtel adds that winter is also a good opportunity to sandblast and repaint the machine, protecting it from rust and corrosion over the off-season.
Tank Cleaning: Inside and Out
The tank interior accumulates sealer throughout the season. Residue builds up on the tank walls, agitator shaft, and blades. When exposed to extreme temperature swings, this material hardens to a brittle or clay-like consistency. If the buildup becomes too large, the agitator may not function properly at the start of the next season, and chunks of dried sealer can clog the filter basket.
Eric Humphries, sales manager at Neal Manufacturing Co., recommends this tank cleaning procedure:
- Drain all sealer from the tank. Cut off the main valve at the bottom of most tanks.
- Introduce raw sealer (sealer without sand) through the ball valve at the bottom of the unit. Allow the system to suck in between 5 and 10 gallons of raw sealer to purge sand from the pump.
- Place the wand into the sealer tank and recirculate the material back into the tank.
- After running raw sealer through the system, flush with water using the same procedure. Two to four gallons of water is usually sufficient.
- Fill the tank with approximately 50 gallons of water, agitate it well, then pump the water out through the spray wand and spray bar.
- For heavy buildup, have someone enter the tank to scrape the interior walls and agitator. Dried sealer often comes off in large chunks that can be removed by hand.
Working inside a sealer tank requires proper safety precautions. Ensure adequate ventilation, and wear rubber boots, coveralls, gloves, and safety goggles. A mask is also recommended to prevent inhalation of dust and debris.
Some contractors try to avoid thorough tank cleaning by suffering through the first few loads of the next season, letting the hardened buildup fall into the strainer basket gradually. This approach causes repeated clogs, production delays, and unnecessary frustration. The best practice is to clean the tank properly during winter downtime so the machine is ready to go from the first load of the season.
Protecting the Pump, Plumbing, and Valve System
The pump and plumbing are the most vulnerable parts of a sealer applicator during winter. If sealer freezes inside the lines, it crystallizes into a thick paste that requires disassembling every fitting and physically removing the material by hand. In severe cases, the entire plumbing structure may need replacement. Proper winterization of these components is essential.
Pump Disassembly and Component Care
The most thorough approach is complete disassembly. Find the lowest point on the plumbing system and remove the plug or open the drain valve to let all water drain out. Bechtel recommends leaving the pump disassembled throughout the off-season, which also makes it easy to examine components for wear.
Key pump components to inspect and replace as needed:
| Component | Inspection Criteria | Replacement Interval |
|---|---|---|
| Pump leathers | Check for cracking, stiffness, and sand scoring | Every 150,000-200,000 gallons or annually |
| Ball valves | Look for erosion channels caused by material blasting at 80-100 psi | Replace if any erosion is visible |
| Hoses and fittings | Inspect for chafing, cracking, and loose connections | Replace any hose showing wear |
| Spray tips and nozzles | Check for uneven spray patterns and orifice wear | Replace if pattern is irregular |
| Filter basket and strainer | Clean thoroughly, check for holes or damage | Replace if damaged |
Critical Order of Operations for Flushing
Humphries emphasizes a critical detail about the flushing sequence. The single biggest killer of leather seals is flushing sealer and sand out with water. The sealer leaves the system, but the sand stays behind. When the pump is started the next season, raw sand scratches the inside of the pump and causes premature wear on the leathers.
The correct procedure reverses the order:
- First, introduce raw sealer (without sand) through the pump to push out the sand-laden material.
- Only after the sand has been removed should you flush the system with water.
Pump leathers generally last between 150,000 and 200,000 gallons of sealer under normal conditions. However, Humphries recommends replacing them during the off-season rather than waiting until they fail in the middle of a production run. The same logic applies to ball valves. Material circulating through a ball valve at 80 to 100 psi can blast a hole in the side of the valve over time. Annual inspection and replacement of worn valves prevents unexpected failures.
The Recirculating Valve
After cleaning, open the recirculating valve to release pressure in the system and allow any remaining material to recirculate. Leave this valve open throughout the entire winter storage period. Keeping it open prevents pressure buildup and allows any residual moisture to evaporate rather than pool inside the lines.
Antifreeze Treatment and Indoor Storage Options
For contractors who prefer not to disassemble the entire pump and plumbing system, an antifreeze treatment provides an alternative layer of protection. While not a replacement for thorough cleaning, this method significantly reduces the risk of freeze damage with relatively little extra effort.
Antifreeze Flush Procedure
To treat the system with antifreeze:
- Pour approximately 2 gallons of antifreeze into the basket strainer.
- Turn on the pump to distribute the antifreeze throughout the entire plumbing system.
- Keep the recirculating valve turned off going into the tank to avoid introducing antifreeze into the sealer tank.
- In the spring, completely flush the system with water to remove all traces of antifreeze before introducing sealer.
Not all manufacturers recommend antifreeze treatment, so check your equipment manual before proceeding. However, most manufacturers acknowledge that it provides an extra level of protection for relatively little additional work.
Indoor Storage: The Best Option
Humphries states plainly: the best way to protect sealer application equipment is to keep it indoors throughout the winter. Indoor storage eliminates the need for most winterization steps because the machine never experiences freezing temperatures. If indoor storage is available, the primary tasks are cleaning the tank, flushing the system, and performing inspections and repairs.
For contractors without heated indoor storage, temporary heating solutions can make a significant difference. A heated storage area or insulated enclosure with a space heater can keep temperatures above freezing and prevent the crystallization of residual sealer. When evaluating your winter storage setup, consider Choose the Right Temporary Heating to Boost Winter options to protect your equipment investment.
If the machine must be stored outdoors, pay special attention to the plumbing system. It is inside the plumbing more than the tank that freeze damage occurs. Pipes, valves, and fittings have smaller diameters and thinner walls than the tank, making them far more susceptible to damage from expanding ice. The pump itself is also vulnerable — water trapped inside the pump housing can crack the casing when it freezes.
Spring Start-Up Checklist
When the sealcoating season approaches, a proper spring start-up routine ensures the machine is ready to work. Regardless of which winterization method was used, follow these steps before the first production run:
- If the pump was disassembled, reassemble it with new leathers and fresh lubricant.
- If antifreeze was used, flush the entire system thoroughly with clean water.
- Inspect all hoses, fittings, and connections for cracks or damage that may have developed during storage.
- Test the pump at low pressure before introducing sealer. Listen for unusual noises and check for leaks.
- Fill the tank with water and run the system to verify spray patterns and nozzle function.
- Check the agitator operation before adding sealer to the tank.
- Verify that all safety systems and emergency stops are functioning properly.
Taking the time to perform these checks before the first job of the season prevents on-site breakdowns and keeps crews productive from day one. For more information on selecting the right sealer for your applications, see Refined Tar Sealer Vs Asphalt Based Sealer a and Refined Tar Sealer Vs Asphalt Based Sealer What.
Winter downtime does not have to mean lost productivity. With a systematic approach to cleaning, disassembly, and protection, contractors can extend the life of their sealer applicators, reduce repair costs, and ensure their equipment is ready to perform when the busy season returns.