AC compressor low oil symptoms

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Here is how to tell if your ac compressor needs oil

To keep your air conditioning systems functioning properly, your AC compressor shouldn’t have too much oil or run low on the lubricant.

With excessive oil, your AC system won’t not cool as it should because the flooded oil hinders the flow of refrigerant through the condenser.

On the other hand, your AC compressor may die prematurely when it’s short of the precious fluid since the moving parts are not lubricated properly.
We reveal the most common AC compressor low oil symptoms in this article.

Keep reading if you think your AC system is malfunctioning because of having inadequate oil.

Table of Contents

There are various signs that tell that your ac compressor is low on fuel.

Here are the most unmistakable signs in an AC compressor that is running low on the lubricant (Note that you may notice one or more signs at the same time).

Symptom 1: Wearing and scoring on the load-bearing surfaces.

One of the first signs is wearing and scoring on rods and bearings.

The cause of this is obvious: the crankshaft is not having enough oil in crankcase to lubricate the running parts so there’ll be more friction.

Here is a summary of the indicators of insufficient lubrication in the AC compressor.

Scored bearings (this we’ve already mentioned).
Score or broken rods.
A scored crankshaft.
Low oil in the crankcase.

Now, in most cases, you’ll likely need to add some oil to your AC compressor before it’s too late.

If not, you might be looking at a huge repair bill or replacement cost for the damaged components.

Symptom 2: Refrigerant leakage

Over time, your car’s air conditioner system may develop a weak point where the refrigerant can escape.

And as it spills out, oil may also be getting out via the opening.

Here is the thing: what may have started as a small seepage may cause a signicant decrease in the amount of the lubricant.

As such, we recommend that you inspect the system and see if you can trace any leakage spots if you have not done that recently.

Something else: the compressor shaft seal is a notorious source of lost oil (or refrigerant) and you need to pay special attention to it if your system is leak-free.

This is especially common in trucks and vehicles that are not on the road on a daily basis.

Plus, leaks in the shaft seal tend to develop after months (or even weeks ) of inactivity.

This is because the part can only be lubricated appropriately when the AC compressor is running.

In short, don’t forget to check the shaft seal even as you examine the rest of the system- for the most part, the compressor shaft seal is usually found in the back of the clutch hub, just below the dust cover.

Needless to say, you’ll need to fix the leak point and top up the oil.

Symptom 3: It’s smoking!

Perhaps, the clearest sign that your AC compressor is running seriously low on the fluid is when it suddenly releases so much black smoke everywhere.

In fact, this could be dangerous as it simply means that oil is almost fully used up (or exhausted).

In this particular case, you should stop the AC system and try to refill it with oil before running it again.

Otherwise, you risk killing it and paying hundreds of dollars (depending on your model) to replace the spoiled compressor.

Note a smoking compressor may mean other things including a bad heater core or a malfunctioning compressor clutch so its important to test these before making any conclusions.

Symptom 4: System heat

Back to the issue of lubrication and there’s a related sign to watch out for: abnormal system heat.

You see, lack of sufficient lubrication (due to shortage of oil) in the internal parts could become manifest in the form of heat in the system.

Here is what brings this:

Since the components are grinding hard against one another and facing more strain during operation, the system heats up since it’s forced to run harder to maintain ideal cooling levels.

Keep in mind that heat doesn’t necessarily imply oil deficiency- it might also point to a deterioration in the oil quality.

You’ll, therefore, require to not only check the current oil amount (and replenish) but also its quality (change it if it has hardened).

Symptom 5: AC compressor emits noises/smells

Another sympton that AC compressor has too little oil is noises or smells.

Still, noises (mostly faint creaking sounds) are mainly caused by poor lubrication in the parts which, as we’ve already seen, points to an oil shortfall.

Alternately, your compressor may start smelling like burnt oil

There are no guarantees and the best way is to have the problem inspected immediately to prevent further trouble.

How to check oil level in AC compressor

Don’t fret if you haven’t seen any of these AC compressor low oil symptoms- you can easily check the amount of oil inside your AC compressor and find out if a refill is necessary.

Yea, there’s no distick to use but it’s not difficult to do.

How to check oil in AC compressor [Procedure]

Simply pull the AC compressor out of the vehicle and drain (use the drain valve) it in a measuring container.

Next, check if the amount that came out is equal to the quantity recommended by the manufacturer for your specific AC compressor.

Your AC compressor is having an insufficient amount if this output falls below the set limit.

Proceed to add or pour out the excess oil (it’s also a possibility) according to the results.