How do you drain oil from an oil pump?

Draining oil from an oil pump is an essential maintenance task that should be performed regularly to keep the pump operating efficiently. Over time, contaminants can build up in the oil, reducing its lubricating properties. Draining the old oil and replacing it with fresh oil helps extend the life of the pump’s components and prevent premature wear. In this article, we will provide step-by-step instructions for properly draining oil from different types of oil pumps, as well as answer common questions about the oil change process.

Why Drain Oil from an Oil Pump?

Here are some key reasons why regular oil changes are recommended for oil pumps:

• Removes contaminants – Bits of metal, dirt, debris and other contaminants that build up in the oil can damage the pump over time. Draining the dirty oil removes these harmful particles.
• Replenishes additives – Oil contains additives that break down over time. Draining old oil and replacing it restores the proper level of lubricating additives.
• Prevents sludge build-up – Old oil can thicken and turn to sludge, which can restrict oil flow and cause blockages in the pump leading to failure.
• Extends pump life – Regular oil changes prevent excess wear and tear on pump components like bearings, gears and seals – extending overall service life.
• Maintains performance – Fresh, clean oil keeps the pump working at peak efficiency and prevents loss of performance.

Changing the oil regularly as part of routine pump maintenance is vital for optimal performance and longevity.

How Often Should You Drain Oil from an Oil Pump?

Most experts recommend changing the oil in an oil pump every 100-500 hours of operation. The optimal change interval can vary based on these factors:

• Pump type – Smaller pumps may need more frequent changes than larger industrial pumps.
• Usage – Oil breaks down faster with heavy continuous use vs occasional use.
• Oil type – Synthetic oils may allow longer change intervals than conventional oils.
• Environment – Oil needs changing more often in dirty or dusty environments.
• Manufacturer specifications – The pump manufacturer may recommend specific change intervals.

Consult your owner’s manual or pump manufacturer to determine the ideal oil change frequency. Track pump hours to stay on schedule with changes.

How to Drain Oil from Different Pump Types

The basic process for draining oil from a pump is similar for most types. But the specific steps can vary slightly depending on the pump configuration. Here are instructions for draining common oil pump types:

External Gear Pump

External gear pumps use external spur gears meshed together to pump fluid. Here are the steps to drain an external gear pump:

1. Run the pump briefly to warm the oil and suspend contaminants.
2. Locate the drain plug on the pump housing.
3. Place an oil drain pan under the drain plug.
4. Remove the drain plug and allow oil to fully drain out.
5. Replace the drain plug when finished and tighten it.
6. Refill the pump with new oil through the fill port to the proper level.
7. Dispose of old oil properly.

Internal Gear Pump

Internal gear pumps use an internal gear meshed with an external idler gear. Draining process:

1. Run pump briefly to warm oil.
2. Position drain pan under pump and remove drain plug.
3. Allow oil to fully drain, then replace drain plug.
4. Add new oil through fill plug to reach proper level on dipstick.
5. Discard old oil per hazardous waste guidelines.

Rotary Vane Pump

Rotary vane pumps use a rotor with sliding vanes rotating inside a cavity. To drain:

1. Locate drain port on bottom of pump housing.
2. Place drain pan underneath and remove plug.
3. After oil fully drains, replace and tighten drain plug.
4. Refill with new oil through fill opening to proper level.
5. Properly dispose of old oil.

Lobe Pump

Lobe pumps use rotors with lobes that mesh to move fluid. Drain steps:

1. Run pump briefly to circulate oil.
2. Position drain pan and remove plug from pump housing.
3. Allow all oil to drain, then replace and tighten plug.
4. Add new oil via fill port until oil level is correct.
5. Discard old oil observing environmental rules.

Follow individual manufacturer instructions for exact steps for your pump model.

Safety Tips

• Allow oil to fully cool before draining to prevent burns.
• Wear protective gloves/eyewear when handling used oil.
• Ensure pump is switched off before beginning drain process.
• Have absorbent materials ready in case of any spills.

Proper procedure is key for safe, mess-free oil changes.

Frequently Asked Questions

Here we answer some of the most common questions about draining oil from an oil pump:

What type of oil should be used in an oil pump?

The oil selected depends on the pump type and manufacturer recommendations, but common choices are hydraulic oils, gear oils, turbine oils and synthetic oils. Use the viscosity grade suggested by the manufacturer.

What is the best way to dispose of old pump oil?

Used oil is considered hazardous waste and should never be dumped down drains or into the ground. Many auto part stores will accept old oil for recycling. Local waste management centers often have special collection for oil disposal.

How do you know when pump oil needs changing?

Look for signs like increased noise/vibration, foam in the oil, sludge build-up, or significant darkening of the oil. Keep track of operating hours and adhere to the manufacturer’s change interval guidelines.

What tools are needed to drain oil from a pump?

Basic tools like wrenches, ratchet/sockets, funnel, drain pan and protective equipment like gloves, glasses and rags. Refer to your owner’s manual for any specialty tools needed.

Can oil changes be done with the pump in place?

Most smaller pumps can be drained oil without disconnecting piping or removing the pump. For larger units, you may need to remove the pump to access the drain plug. Check instructions.

Is it ok to run a pump with old oil?

It’s not advisable to exceed the recommended oil change interval. Old contaminated oil can lead to increased component wear, sludge build-up and ultimately pump failure.

Conclusion

Regularly draining used oil helps maintain any oil pump’s performance and service life. While specific steps vary by pump type, the process generally involves warming the oil, positioning a drain pan, removing the plug to drain, replacing the plug, refilling with fresh oil, and properly disposing of the old oil. Safety is paramount when handling used oil. Following the manufacturer’s specifications for oil type and change frequency is recommended. With a simple, routine oil change process, oil pumps can deliver reliable operation for years.

Pump Type	Oil Change Steps
External Gear Pump	Warm oil by running briefly Position drain pan & remove plug Allow oil to fully drain Replace drain plug Refill with new oil to proper level Dispose old oil properly
Internal Gear Pump	Run pump to warm oil Place pan, remove drain plug Let oil fully drain, replace plug Refill oil to correct level Discard old oil observing regulations
Rotary Vane Pump	Locate drain port on pump housing Put pan in place, remove plug Once fully drained, replace plug Refill with new oil to proper level Dispose of old oil properly
Lobe Pump	Circulate oil by running briefly Drain pan under, remove plug Allow complete drain, replace plug Add new oil to correct level Discard old oil per environmental rules

Key Oil Change Tips

• Consult manufacturer guidelines for proper procedures
• Allow oil to cool before draining to prevent burns
• Wear protective equipment when handling used oil
• Ensure pump is switched off before starting
• Have absorbent materials on hand in case of spills
• Dispose of used oil responsibly – not in drains or ground
• Adhere to recommended oil change intervals