You and your friend have the same car but his/her is performing better and returning better efficiency? And you keep wondering why this is happening? Your break-in period might just have made all the difference.
a. What is break-in period?
A newly manufactured engine that hasn’t been run at all, needs to be taken care of for some kilometers so that it sets in or breaks-in before it can be used to its full potential. This period is its “break-in” period. Operating the engine in the wrong manner could reduce its performance and efficiency to a great extent for its entire life.
b. Things to keep in mind during the break-in period:
- Know your break-in:
First thing to do is to get to know your vehicle’s break-in period. It could be different for different vehicles depending upon your vehicle’s engine. If you can’t find it, then go for 1000kms i.e. drive your vehicle carefully (read below) for the first 1000kms of the vehicle.
- Don’t run the engine for short distances:
When a vehicle’s engine is started, it takes some time to reach its ideal running temperature. Travelling short distances does not allow the engine to reach its ideal running temperature which isn’t good for it on the long run.
- Don’t run the vehicle for long hours at constant speeds:
Taking a new vehicle for a long drive is not a very good idea. The engine needs to be exposed to varying temperatures and pressures hence it’s good to drive it at varying speeds. Driving at a constant speed will make the temperature almost constant. You don’t want the engine to get used to that speed (temperature) only.
- Don’t redline your vehicle:
Not all vehicles have a tachometer, but most do. A tachometer is a gauge generally located besides the speedometer. It shows the Revolutions per Minute count of the engine’s crankshaft or in other words, the speed of the engine. The tachometer always displays a redline on it, meaning that if your engine is capable of running up to, say 6000RPM, then the tachometer will show everything above 6000RPM in red color. Never run your engine to its redline during the break-in period. Doing so causes excessive wear to the engine cylinder resulting in leaks and frequent visits to your service dealer.
- Don’t floor it:
Never apply full throttle before engine break-in. This again causes excessive wear to engine parts leading to a short engine life.
- Set an RPM limit:
People generally misunderstand this point. Let’s say that you got a new car. Your friend tells you that you should not drive it above 100kph during the first 1000kms (1000kms being the break-in period here). THIS IS WRONG.
Why? Here’s why. As already discussed, the tachometer shows us the engine speed. Let’s say that your engine’s idling speed is 1000RPM and redline is at 6000RPM. This means that according to your friend, you can apply full throttle in gear 1(all the way 1000RPM to 6000RPM), shift to gear 2, apply full throttle again (2000RPM – 6000RPM) and so on until you have reached 100kph. This process includes both, flooring and redlining the vehicle. Both things that should NOT be done. Your brand new car will soon want to go for frequent check-ups because of the damage done to its engine parts.
Instead, set an RPM limit. Say for your car’s model, it is 3000RPM. Drive your car up to 3000RPM in every gear. 3000RPM in gear 1 could be 25kph, gear 2 could be 40kph, gear 3 could be 70kph, gear 4 could be 95kph, gear 5 could be 110kph and gear 6 could be 128kph. (These speeds depend upon the gear ratios set by the manufacturer. They are different for every model.)
Here, you’re taking care of your engine’s operating speed instead of your vehicle’s operating speed (speed of the wheels). The RPM limit during the break-in period is different for every model. It is generally provided by the manufacturer. Normally, it is 3000-4000RPM for petrol fueled vehicles. If you have difficulty finding your engine’s RPM limit, simply divide the redline by 2. So if you’re engine is redlining at 6000RPM then you should drive it below 3000RPM during the break-in period i.e. in this case, 1000kms.
Let’s take the Nissan GTR as an example:
The above image shows the tachometer of a Nissan GTR with its redline at 7000RPM. Nissan recommends driving the GTR upto 3500RPM during its break-in period of 350 miles.
c. What’s happening inside:
Brand new vehicles have freshly bored engine cylinders. The pistons running in these cylinders have piston rings that have not yet formed a perfect seal in the cylinder. An engine is said to break-in when the piston rings have locked properly on the cylinder and formed a perfect seal. In an improper engine break-in, the piston rings leave gaps due to excessive wear causing leakage of fuel in the cylinder deeply impacting performance and engine efficiency.
As we all know, different physical and chemical properties are observed during slow heating and fast heating of a metal. Similarly, the engine is also effected differently. Running below ideal engine temperature, flooring, redlining, driving without an RPM limit, etc. result in undesirable physical and chemical properties of the engine block. Hence it is recommended to set an RPM limit during break-in period.
So the next time you or someone you know gets a brand new vehicle, you know what to say and what to do.