Turbos and Heat: They Get Hot, Hot Hot!

One of the most interesting parts of trade shows is the educational aspect. I’m not simply referring to the seminars and classes many shows offer. Rather, I am referring to the displays many companies produce that show us how things work. 

I remember a display at the Louisville Truck Show that had a transmission made of see-thru plastic so one could witness the manner in which gears and fluids interacted. It was fascinating, especially because we’re accustomed to only seeing the opaque external shell. 

This brief blog post has to do with turbochargers and heat. Turbos are a forced air induction device designed to increase an internal combustion engine’s efficiency and power. (Regular engines rely on air pressure and normal air-flow.) Essentially, the turbo is a compressor that enables more air to be forced into the combustion chamber, along with more fuel.

It was at the AAPEX Show during SEMA Week a few years ago that I saw the most interesting cutaway of a turbocharger. In fact, it was a virtual 3-D projection like a hologram. Someone there pointed out several features, and explained how hot this little spinning area gets. In short, if you don’t have a lubricant up to the challenge, it’s going to be trouble for you.

One of the functions of oil is to reduce friction, a major issue when you consider the RPMs at which a turbo spins. (We’re talking 80,000 to 250,000 RPM, if you can wrap your mind around that.) A second function of the oil is to carry heat away from the hot spots to cool elsewhere. Poor quality oil won’t do either job well, if you have really poor oil it can form carbon deposits, which you really don’t want.

 

Another reason this area of the engine gets so doggone hot is that it’s powered by exhaust gases, which are already hotter than blazes.

Heat can be a real problem, which is why there are precautions associated with turbos. First, researchers have noted that turbochargers have to be carefully matched to the engines they serve. Second, because they get so hot, especially after a hard run, you need to let your engine idle a little before shutting it down. I’ve been told that this one little trick will trick can add significantly to the life of your turbo.

Since replacing a turbo can cost a pretty penny, increasing your turbocharger’s service life is a wise thing to do. You may be able to cut costs with aftermarket replacement parts, but you still want to make sure you have someone help who knows how to do the work. 

There are many little things you can do to make your turbocharger last longer. One of the simplest things to do for preventive maintenance is to check you oil and fluid levels. If the supply is not sufficient to properly lubricate the system, a lot of bad things can happen.

Photo: Remanufactured Cummins Turbo