Fuel Pump Losing Prime: Causes & Solutions

Naomi O'Colman

Fuel Pump Losing Prime

Fuel Pump Losing Prime

Whether they are used for industrial, domestic, or irrigation purposes, all pumps operate in the same way. Therefore, maintaining your pumps’ efficiency can help you save a lot of time and money. You can try a number of different things to figure out what might be causing your fuel pump losing prime.

What Is Priming of A Fuel Pump?

Sensing the rise in fuel pressure during priming is a step in a fuel system priming procedure for an internal combustion engine with a returnless fuel system and electronic fuel injection. To release trapped air in the fuel system, the injectors are first managed for a brief period of time in response to the observed rate of pressure rise after the fuel pump has been initiated to pressurize the system. The completely primed fuel system is then pressurized for a speedy engine start by turning on the fuel pump once more.

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Having stated that, we must prime the fuel system once the motorcycle runs out of fuel before attempting to start the engine again. Here are some short actions you can take:

  1. Refuel the vehicle.
  2. In the ON position, turn the ignition key.
  3. Put the RUN position on the engine stop/run switch.
  4. The fuel pump should be left running until it stops (about 2 seconds).
  5. Place the STOP position on the engine run/stop switch.
  6. Steps 3-5 should be repeated 4-5 times.
  7. In the OFF position, turn the key.
  8. Start the car.

Why Is the Fuel Pump Losing Prime?

1. Fuel lines with leaks and cracks

Fuel line damage is a common cause of fuel pump issues (This could account for 90% of cases). Your pump may lose prime if there are leaks in the intake line, around the housing’s shaft seal, or elsewhere.

Sometimes the cracks are so minute that you can’t see them with a fast visual inspection, yet they’re big enough to prevent the fuel from continuously draining from the tank.

Solution: Change the hoses as a fix.

2. Valves

The intake line and casing of the majority of pumps are kept full with water, gasoline, or diesel by foot valves when the pump is not in use. Therefore, your pump may lose prime between starts if your foot valve leaks.

Solution: Replacement of the problematic valve may be the answer.

3. Blockage

An obstruction or blockage in a line could be one reason your pump is losing prime. The most frequent cause is debris obstructing the foot valve or suction strainer. In addition, the fuel inside the pump casing may practically boil out of the casing due to an obstruction in the intake line, which would cause the pump to lose prime.

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How to Make Fuel Pumps Last Longer

Here are some tips to keep your fuel pump last longer:

1. Never leave the gas tank empty

You can’t allow the fuel to get down to one-fourth of a tank. The pump generates heat while it operates because it is an electrical device. Thus, to keep the tank cool, the pump was placed inside. The aim won’t be accomplished if it is not constantly submerged in gas. Additionally, the pump may experience a thermal shock if gasoline is quickly put into the tank when it is empty.

2. Do not mix dirt and petrol

Nowadays, gasoline contaminated with the debris is less frequent because most stations strive to maintain high-quality fuel. Try not to fill up the tank at the gas station while you are getting gas, though. All the dirt and deposits are churned up in the gasoline that is being stored when the station is getting gas. The pump filters won’t be able to collect them all if you put that fuel in your car.

3. Replace the fuel filters

Fuel filters need to be changed annually. It is crucial to change them so that no debris can enter the pump, regardless of what is stated in the owner’s manual or how far you have traveled.

4. Use an anti-ethanol agent

Today, ethanol is added to fuel blends. Ethanol benefits the environment, the agricultural economy, and the reduction of reliance on foreign oil. Add an anti-ethanol compound to the fuel if it is not being used completely after a week or two. Otherwise, problems with the fuel system can arise.

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The delivery of fuel to the engine is a vital function performed by the fuel pump. Make sure you take care of it to prevent problems with the fuel pump, such as priming.