AVOIDING PROBLEMS WITH TURBOCHARGERS
Are cars with turbocharger problems becoming a real headache for your auto repair shop? Here are a few pointers to help you keep them at bay.
If you own an auto repair shop, you're probably all too familiar with power loss, noises and white smoke. These are usually signs that the turbocharger is about to fail, a fairly common problem, especially for small engines that deliver greater torque and power and may be equipped with a particulate filter.
These engines perform extremely well, but are subjected to extreme stress as a result of high operating pressures and temperatures. That means the engine parts work hard. The problems described above are likely to arise when a vehicle is not maintained according to the manufacturer’s instructions. They are harbingers of imminent disaster: turbocharger failure.
(Unwelcome) Surprises You May Come Across
When you take the turbocharger apart, a few surprises may be lying in wait, such as a broken shaft, loose parts or a loose or missing locknut. If you can’t spot the locknut, look for it! If it’s left inside the engine after repairs, the turbocharger could fail again.
Generally speaking, when you drain the oil you'll see that it has been badly damaged, contains carbon contaminants and is much more viscous than normal (your customers would probably describe it as being “too thick”). When carrying out repairs, you'll also see that the cylinder head is soaked with sticky oil and that the turbocharger air filter is blocked, preventing the oil from getting through.
The contaminants are caused by combustion and mostly occur under severe driving conditions in the city, when cars travel at a slow speed for relatively short distances. These conditions lead to the formation of a large amount of contaminants that mixes with the oil, thickening it. There may also be problems with the air intake system, i.e. the filter and ducts; if less air is entering, combustion will not be as efficient as it should be.
Oil thickens much more at the points where it meets greater resistance as it attempts to flow through. That means the oil filter is most affected, because its job is to block dirt.
As a result, the turbocharger’s bearings and shaft will be poorly lubricated. This causes noise in the turbocharger and may even lead to failure in extreme cases. That's because very little oil reaches the components, which then experience excessive wear and tear. Generally speaking, the turbocharger repair kits currently available do not include an oil filter, which would ensure that the lubricant continues to do its job.
A Recurring Breakdown
Although you may have solved the problem this time, it is a fairly persistent one that may recur. To avoid this, make sure you:
- Check the air filter and the intake circuit: Insufficient air intake may lead to the excessive formation of carbon due to incomplete combustion. This will affect the oil and make it more viscous.
- Make sure that all parts have been replaced properly: Check that the locknut has been replaced and that no pieces of the blades or dirty oil residue have been left behind, which could lead to another failure. The engine often has to be cleaned using fresh oil, which should then be removed.
- Check that there are no pieces of metal inside the oil pan: Flush the oil pan if necessary and thoroughly check the air intake screen and the drain plug washer, among other things.
- Remove any dirt that has built up inside the system: Once the repairs have been completed, you can use a special product to clean the engine´s lubrication system. Let the engine idle for 10 to 15 minutes, drain the oil and remove the filter. This ensures no dirt remains in the system.
- Check the lubrication system pressure to see if a part is blocked and preventing the oil from circulating.
And What If It Happens Again Anyway?
As we mentioned earlier, this can be quite a persistent problem. Even if you follow these instructions to the letter, the car may well wind up back in your shop with the same problem. This has a lot to do with your customer’s driving style. For this reason, manufacturers recommend severe condition oil changes, especially the first time the turbocharger fails.
And of course, if the wrong oil is used or is incorrectly drained, problems with the turbocharger may become frequent. Manufacturers therefore recommend the following:
- Engine oil: For this type of engine, manufacturers usually recommend synthetic 5W-40 or 5W-30 oil. The 5W-30 oil must be compatible with the particulate filter, if there is one. Yes, 15W-40 and 10W-30 grades have been banned. That's because synthetic oil has better detergent action and is more able to prevent the carbon contaminants from binding together and causing the oil to thicken. As a result, it's easier for the oil to pass through the turbocharger filters.
Only use premium oils that comply with the manufacturer’s specifications and follow the strict oil change instructions exactly. This is always important point, particularly so here.
- Oil change: You must follow a system to drain these engines correctly. Any old oil left behind will contain carbon contaminants. Therefore, never ever (repeat after me, please: NEVER EVER) drain the engine from the top using a pump (suction). The oil should be removed while still warm. Loosen the oil filter to help the drainage process and remove the drain plug. Then let the oil run out for at least 10 minutes. Once empty, install a new filter; if you skip this step you’ll be left with dirty oil that will cause problems in future.
If you follow the advice you get here at Total, recurring turbocharger failures will stop being such a headache for your repair shop.
- Always perform severe conditions oil changes for this type of engine. The oil should be changed every 15,000 kilometers or at least once a year.
- Remind your customers to check the oil level regularly and top it up when necessary. The level should fall between the maximum and the minimum.
- Use synthetic 5W-40 or 5W-30 grade oil for this type of small engine.
- Some manufacturers recommend cleaning the engine using an approved product that can be added to the oil between each change. That said, this recommendation has not yet been included in owner service manuals.
It goes without saying that you shouldn't use just any oil. Make sure that the oil meets the manufacturer's quality standards. This is an excellent way to keep engine problems at bay and increase customer satisfaction.