Product Categories


The Unknown danger of engine sludge

CARvity's’ attention has been beamed lately on the silent but potent issue ravaging many car engines across Nigeria, mostly in Lagos. Amazingly, the insidious death of these engines is caused mostly by the same thing


CARvity’s’ attention has been beamed lately on the silent but potent issue ravaging many car engines across Nigeria, mostly in Lagos. Amazingly, the insidious death of these engines is caused mostly by the same thing that should naturally preserve them: engine oils. The lethal harm here is caused by what in automotive parlance is called “Oil sludge”.

Oil Sludge is a solid or gel in motor oil caused by the oil gelling or solidifying, usually at temperatures higher than 100 degrees Celsius. After prolonged exposure to high heat, engine oil can oxidize and break down, forming deposits known as sludge. This gelatinous slop can block vital oil passages, resulting in extensive damage or even requiring an engine replacement.

Causes of Oil Sludge:

While high temperatures are implicated in the gelling of these oxidized oil, they are not the main culprits here. After all, engines are meant to generate some level of heat for optimal performance. The lead causes of sludge thus include:

  • Oil changes that have been neglected.
  • Driving a car extensively with an extremely low oil level.
  • Frequent stop-and-go driving or short commutes
  • The presence of water in the engine oil
  • Poorly designed or defective crankcase ventilation system
  • Low engine operating temperatures

Clearly, from the causes outlined above, it is obvious that the easily preventable causes are those listed in the top two. On the first, this post will dwell more.

Detection of engine sludges:

Is my car’s engine secretly nursing this unpleasant surprise? Is there oil sludge creaming its way up somewhere in my car’s engine? If you are wondering how to know if there is a sludge build up in your vehicle, these are a few checks you can do, of course, depending on your car.

  1. Crank your engine and look to your dashboard for the ‘check engine light’. Although this is not the only thing that elicits a check engine light, yet I know that here in Nigeria, this warning light is very belittled and even misunderstood. Some car owners would assure you that their cars have had a check engine light since purchase and it has served them for 4years without hiccups. Well, it’s only a matter of time, that hiccup is coming for sure! So, try not to take that light for granted especially if you also notice the oil change notification light. Do a quick servicing to ensure an elongated lifespan of your car’s engine.
  2. Turn off your engine and pop the bonnet. Look around the engine for thick oil clumps (sludge). Where none is seen, take a step further and open the oil cap and peer inside. Please ensure the engine is turned off. Look for thick, viscous oil around the cap and on the metallic surface of the inner components of the engine. While you should see oil on these parts, it shouldn’t be viscous, dark or in clumps. That is sludge right there and should be gotten rid of, immediately.
  3. Ask a well-trained mechanic to assist you with a more professional check. The key word here is ‘well-trained’.

Prevention of sludge:

  1. Service your car in strict compliance with your manufacturers guideline for frequency (mileage) of services and oil type. Change oil and oil filter in accordance to these guidelines. Don’t know where to find your manufactures recommendations? Check the car manual and if yours is missing, go online and you might either be able to order an e-version or find car forums where these specifications are discussed with reviews.
  2. Reduce short commutes and stop-and-go driving. While that seems practically unavoidable in Lagos, Nigeria, it means also, that if your daily route demands a lot of stop-and-go driving, then you will need to service more often than those who have the highway to play with every day.
  3. Check for sludges in your engine periodically using the suggested measures earlier mentioned.

How to remove sludges:

  • Use an Engine Slush: While there are sources that will either debate or discourage you on this, they are the easiest ways to get rid of engine sludge. They are typically added to the old oil, then you idle the engine for 5-10 minutes without driving it.  This gives the chemical solution time to solvate the sludge and draw as much of it as possible back into the oil.  Then you change the oil and the engine sludge is removed along with the old oil.  Be sure to follow the specific application directions for whatever you are using.
  • Depending on the extent of sludge garnered in your engine, it might need serious mechanical attention and your mechanic (hopefully experienced) is the best man for this job! This is the surest way to rid your engine of the killer sludge but easily the most invasive and expensive options. But then, it’s a case of remedy or replacement, you choose.

Going Forward: If after you have gotten your engine free from the lethal claws of the sludge that once threatened its existence, this might be the best time to be more deliberate about the engine’s service routines as well as the precision of same in line with manufacturer’s recommendation. If you are thinking of going forward with that vehicle, there’s really not much of a choice.