Their structure is very different from the regular gasoline engines and they are reinforced with heavy-duty parts like heavy-duty pistons and rods, heavy-duty bolts, and much more. Parts that can withstand anything and keep going.
We spoke a whole lot about why exhaust brakes will not damage the engine. But what is it really? And how does it work? Exhaust brake is a device that helps a diesel engine to make a full stop. Exhaust brake works by using an exhaust valve that closes and creates a major restriction in the exhaust system — adding force against the piston to slow it down.
When an exhaust valve is closed substantial exhaust gases and back pressure are created. They eventually flow back into the combustion chamber against the movement of piston — causing pistons to slow down or stop moving entirely. Thus, creating the braking effect. Exhaust brakes are known for their effectiveness and can provide a full stop braking of a fully-loaded vehicle even without applying the ordinary brakes — tough stuff. Exhaust brake has a valve that opens and closes.
When closed, exhaust gases cannot pass through and this creates a backpressure that travels into the cylinder — resisting the movement of pistons. Exhaust brakes should be used in instances where powerful braking is required. For instance, slowing down a fully loaded truck when downhill on a traffic.
Or during an emergency where you absolutely need to stop the vehicle. So, only use your exhaust brake in a state of emergency. Wherever possible, you should use the regular disc brakes first. Exhaust brakes significantly slow down your diesel vehicle quickly. This means, you will need to use up more diesel fuel to re-accelerate and gain speed again.
These three types of braking can be confused with one another but they work quite differently! I will cover each of them a bit more after.
Exhaust brakes are used mainly by diesel engines, they compress the exhaust gasses into the manifold where they flow back and stop the movement of pistons. Exhaust brakes are usually used for big trucks where the brake discs alone are not powerful enough. A marginal sacrifice in performance may accompany the install, but it's negligible unless you're looking for total performance. The trade-off is well worth it if you use your truck for its intended purpose. Exhaust brakes are available for a variety of applications, although some naturally aspirated engines may not be compatible.
How Exhaust Brakes Work Exhaust brakes help a truck slow down by restricting exhaust flow. More From Diesel Hub. Then it closes and restricts exhaust flow by keeping it in the cylinder. This causes the piston to force the compression into the exhaust brake, which absorbs the energy [source: Purcell ]. A little confusing? Think of it this way: Take a deep breath and hold it in. Now force the air into your mouth and cheeks, but don't let it out.
You've just created your own little exhaust brake. Exhaust brakes don't produce the loud blatting sound for which engine brakes are known. They actually make no sound at all. We could, at least in theory, slam on the exhaust brake to the point of sliding the rear wheels — not a good plan when towing a trailer downhill. Consequently, we want to temper the exhaust brake action for a reasonable, controlled degree of braking.
Besides, an exhaust brake cannot close the exhaust system completely for a number of other good reasons. If the exhaust is completely closed, the pressure in the exhaust system will continue to rise until either the exhaust system ruptures or engine damage occurs.
Consequently, an exhaust brake must vent some exhaust flow through the exhaust system to keep the peak system pressure below the danger point. The pressure at which the exhaust valves can be blown open depends on the valve spring seat pressure and size area of the valve head of the valves used. This is a carefully engineered setting on all Banks Brake applications: a careful determination is made to produce maximum practical braking without causing engine damage.
First, if creating backpressure in the exhaust system generates negative torque and engine braking, then any exhaust system restriction that prevents free exhaust flow during cruise conditions or full throttle operation actually detracts from power output and fuel economy in the same way. Secondly, when closed, an exhaust brake stalls the turbine section of the turbocharger. The exhaust brake must open before the turbo can spool up again to provide boost on demand.
The Banks Brake is engineered to open at speeds below 15 MPH, when very little exhaust braking is available anyway, to quicken turbo response when the driver again steps on the fuel pedal. Only the Banks Brake has this computerized feature.
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