Why do diesel engines clatter

Current work is focused on development of metrics that accurately reflect human responses to gear rattle. Subscribers can view annotate, and download all of SAE's content. Learn More ». Browse Publications Technical Papers Citation: Sobecki, B. Change is coming, both quickly and dramatically.

But legislators are moving against this flank too, with many European cities set to introduce zero-emissions zones that will ban even the cleanest diesels.

The Insider. Two types of sounds There are two sound types that emerge from a diesel engine. Combustion Noise Mechanical Noise Combustion noise is created by the compression ignition process which compresses the air fuel mixture of the gas which creates higher temperatures upon increased compression until combustion occurs.

DucatiKiller DucatiKiller I would rephrase the Combustion noise statement. With the compression ignition first the air is compressed until it is very hot, there is no fuel in the cylinder at that time. Once the compression is near complete an injector sprays the fuel directly into the cylinder. The interaction of the fuel with the hot air as it ignites is what creates that unique noise. Brittany Gunshore Brittany Gunshore 21 1 1 bronze badge. Not all guys are averse to females in traditionally male occupations.

Those that are like that are slowly dying off. By all means share your knowledge and expertise. How is this different from spark-ignited engines advance? I suppose in a spark ignited gasoline engine the flame front starts very small around the plug and then advances smoothly through the cylinder. Featured on Meta. Now live: A fully responsive profile. Version labels for answers. Linked 0. Related 1. Hot Network Questions. The videotape was produced by a repo man, somebody who is hired by lending institutions to repossess cars.

GM is doing something about the problem. The auto maker has introduced a new anti-theft system, called the PASS-Key, that shuts down the fuel system if somebody tampers with the ignition system.

It is now found on the Camaro. I want to compliment the several readers who faulted a recent answer of mine to P. I told him that the reason was possibly that his old Buick was heavier and perhaps had a V-8 engine. Heavier cars absorb sound better--and V-8 engines generate less noise--than four-cylinder cars.

I based my answer on some advice from automotive experts. But several readers who are obviously experts in their own right pointed out that the Buick Somerset did not come with a V-8 option.

Since then, I have also received a good deal of comment from current and former Camry motorists about the noise levels in their cars. Having recently test-driven a Camry, I would agree with P.

Vartabedian cannot answer mail personally but will respond in this column to automotive questions of general interest.