Contree Sprayer & Equipment Company, LLC    
(800) 433-3579
Because you value your profit as well as the environment, here are some frequently asked questions and answers to help you maintain both.

We are committed to providing the best possible service, which includes your knowledge for maintenance of your sprayer parts as well as safe application tips for protection of our environment.

  1. How do I calibrate my sprayer?

  2. How do I know which tip to choose for my application?
  3. How do I calibrate my spray tips?
  4. How do I calibrate my handgun sprayer?
  5. How do I know when to replace the diaphragms in my diaphragm pump?
  6. What oil do I use in my diaphragm pump?
  7. How do I maintain my sprayer parts?
  8. What do I do to my tank if I want to spray a different application?
  9. What do you recommend for winterizing my sprayer?

  10. I have pressure on my handgun hose, but as soon as I pull the trigger, the pressure drops to nothing.
  11. There is no oil in my sightglass on my diaphragm pump.

  12. How can I keep my hose reel rewinding smoothly?

 

 

 

  1. How do I calibrate my sprayer?

    This is a complicated answer that we will answer in steps.

    A. Check your sprayer speed.
    Measure off a 200 foot strip in a field. Start far enough behind your 1st marker to reach the desired speed before you pass it. Note the time it takes to travel this distance and use the table below to calculate your actual speed in mph.

    Time (Seconds)
    required to travel 200 ft.     		45 34 27 23 19 17 15 14 12 11 10.5 10
    Speed
    (MPH)     		3 4 5 6 7 8 9 10 11 12 13 14

    B. Select the most suitable type of spray tip using the recommendations on the chemical label and the tip selection guide. This is very important!

    C. Select the correct spray tip capacity.
    Use the following formula to calculate the flow required per spray tip in gallons per minute (gpm): Then, using the gpm figure from your calculations consult the "flow" column for the correct size of spray tip.

    GPM = GPA x MPH x nozzle spacing (inches)
    5940

    D. Check the system.
    Before spraying, check the system for blockages, leaks, kinked pipework, etc., and the spray tips for damage or wear.

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  2. How do I know which tip to choose for my application?

    Select the most suitable type of spray tip using the recommendations on the chemical label and the tip selection guide.

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  3. How do I calibrate my spray tips?

    Before calibrating spray tips, ensure that the spray liquid has a clear passage to the tips by checking and cleaning all strainers and removing any restrictions (hose kinks, etc.) in the pump feed and delivery lines.

    Also, check for air leaks and that your pump is performing adequately. From the calibration charts find the correct flow per minute for your tips to produce the application rate you need at the required speed and pressure.

    Carefully, set the required operating pressure of the sprayer. Using a watch and measuring jug, check a single tip flow on the sprayer at that pressure. If the output differs slightly from that required, small adjustments may be made by adjusting pressure using the pressure regulator (but only within the recommended pressure range) until the correct rate is achieved at the spray tip. Should the output of the tip differ by a large amount from that required, do not attempt to rectify this by pressure regulation.

    Remember, pressure must be changed by a relatively large amount to achieve a modest adjustment in the tip output so you run the risk of dramatically altering the spray quality. In this case, it is better to change to the next appropriate tip size. If the flow from any tip is 10% greater than that shown in the appropriate calibration chart at the same pressure, then replace the tip. If more than one tip appears faulty, then replace all tips on the boom in order to maintain an even spray coverage.

    Remember also to check for spray tips showing broken or uneven spray patterns. Re-calibrate your spray tips after every 250 acres using clean water. Remember....ALWAYS use the correct type of spray tip for the job. Carefully follow the chemical manufacturing recommendations. Do not try to use the same spray tips for all applications.

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  4. How do I calibrate my handgun sprayer?
    A) Measure out a 30' by 30'4" rectangle on flat dry pavement.

    B) Fill sprayer with clean water and set unit at desired spraying pressure and bleed out any air that may be in the handgun hose.

    C) With a stop watch, measure the time it takes you to spray the 1000 square foot rectangle at a comfortable walking speed.

    D) Repeat three times and take an average of the times.

    E) Next, spray the handgun into an empty calibrated container for the averaged time above. Repeat three times and average the water levels in the calibrated container. This averaged amount is what you will spray on every 1000 square feet.


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  5. How do I know when to replace the diaphragms in my diaphragm pump?

    Change pump diaphragms and oil for every 500 hours or 3 months of use. Be sure you flush your pump after every use!

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  6. What oil do I use in my diaphragm pump?

    Use non-detergent SAE 30 weight oil or new specially formulated Hypro pump oil. Check oil in the pump and gear reduction every day. Replace oil in gear reduction every 500 hours and use SAE 80W-90 gear lube.

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  7. How do I maintain my sprayer parts?

    Clean line strainers daily. Be sure not to lose the strainer bowl gasket. It is always a good idea to keep an extra gasket, screen and strainer bowl on hand. Lube your strainer gasket with petroleum jelly to aid in seating. Repair leaks as soon as they are noticed to avoid excessive loss.

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  8. What do I do to my tank if I want to spray a different application?

    The important thing here is that you adhere to the following advice on a weekly basis, regardless of whether you change applications or not. Clean your tanks weekly, inside and out. Household ammonia works well; use 1/2 gallon ammonia to 25 gallons water. There are other products on the market , among them is Tank Clean. Ask your chemical dealer for other available tank cleaning products.

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  9. What do you recommend for winterizing my sprayer?

    Before storage, triple rinse your sprayer, filling the tank 1/4 to 1/2 full for each rinse. Clean tank as directed above. Mix 10 gallons of 50/50 mixture of water and antifreeze. Be sure to run it through the hose reel and handgun by holding the handgun valve in the on position until 50/50 mixture comes out. (100% RV antifreeze may also be used.) It is important to remember that if tanks are not properly rinsed, the chemical residue can damage costly parts of your sprayer and decrease its operational life.

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  10. I have pressure on my handgun hose, but as soon as I pull the trigger, the pressure drops to nothing.
    Check for air leaks on the suction side of the pump. Be sure that nothing is blocking the inlet line on the inside of the tank.

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  11. There is no oil in my sightglass on my diaphragm pump.
    Check to make sure the diaphragms are not damaged or worn. Do not run your pump if there is no oil in the sight glass.

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  12. How can I keep my hose reel rewinding smoothly?
    Check alignment of drive motor sprocket and reel sprocket. If either or both are out of alignment, realign or take in to qualified reel repair center. Oil chain weekly with a light coat of chain lube, available in aerosol spray cans at almost all auto parts stores. Check reel bearings for wear and keep oiled. This allows hose to reel out evenly and cause less strain on the reel motor when rewinding hose.