How to Check Oil Levels Manually and Fix an Oil Tank Gauge



Basic oil tank maintenance, such as checking oil levels and straightforward fixes, can help to reduce the risks of breakdowns or of being left without oil. So to help you keep your oil tank in good health, we’ve created this straightforward guide. 


What is the purpose of an oil tank gauge?


Typically found inside the tank, the gauge displays the amount of oil currently within the tank in either quarter-inch or eighth-inch measurements. 


Measurements from an oil gauge are generally accurate, though there are a number of different factors that may affect the reading, including:


  • If the oil gauge is damaged

  • If there is water or air in the tank 

  • The overall shape of the tank


Developing an understanding of your gauge can help when diagnosing problems and establishing whether an issue requires a quick fix or the attention of a contractor. 


How to manually check your heating oil level


While a gauge is designed to give a reading of the oil within the tank, it is not always accurate. Instead, a manual check is often more likely to provide you with a precise result.


To manually check your heating oil level, you should use a gauge stick. A gauge stick should give the most accurate reading due to its varnish finish reducing the oil spread, but a wooden or metal rod can also work.


To manually check your heating oil level:


  • First, remove the valve cap of the oil tank by turning it counter-clockwise.

  • Slowly lower the gauge stick into the oil tank until you touch the bottom.

  • Remove the gauge stick and check the reading for the level of oil.

  • Write down the measurement in the manual tank gauging record.

  • Clean the gauge stick with a dry cloth and lower it again into the oil tank for a second reading.

  • Record the second set of results.

  • Replace the valve cap on the oil tank.

  • Repeat this process every week, remembering to record your measurements in the manual tank gauging record.


Having collected the oil tank measurements, you will next need to understand what they mean. A fuel oil tank chart will allow you to convert the inches you recorded into gallons. 


When should you refill your oil tank?


The amount of oil you use will depend on a variety of factors, such as the time of year and the size of your property. 


Throughout the winter months, an average household will burn through around 100 gallons a month. It is crucial you avoid allowing your oil gauge to fall below a quarter-inch, so for an average tank, you will need to refill it at least once during the winter months. 


The risk of overfilling your oil tank


Overfilling your oil tank can lead to spillages, which is why it is vital you know how much oil is in the tank. 


Oil can be hazardous to humans, so an overflowing tank could result in health problems for both you and your family. The vapor from the oil can cause headaches and nausea, while the oil itself can cause skin to become highly irritable.


Oil is also highly flammable so, if your tank overflows, you will need to extinguish any nearby naked flames and clean the area immediately. 


An overflowing oil tank can also be incredibly damaging for the local environment, especially if it manages to find its way into water supplies. You need to be aware that you will likely be held liable for any damage caused by spillages originating on your property.


How to fix an oil tank gauge


If your oil tank gauge does break, thankfully, it isn’t too difficult to replace it. To start, you are going to need:


  • a replacement oil tank gauge

  • oil lubricant 

  • anti-seize lubricant

  • a wrench 

  • a hooked wire

  • a flashlight


To begin fixing the oil tank gauge, you should do the following:


  • First, apply the oil lubricant to the cap of the tank to help remove it.

  • Gently use the wrench to remove the cap. Remember to be careful to prevent damage to the threads.

  • Look for the old float gauge arm in the tank, and with the hooked wire, pull it out. The flashlight will help massively during your search for the gauge arm.

  • Next, replace the old gauge in the gauge pipe with the new one.

  • Return the gauge pipe to the tank.

  • Replace the cap using the anti-seize lubricant on the threads to firmly secure it.

  • Finally, make sure to regularly check the new gauge to ensure it remains in working order.


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