It is normal in diesel engines although they are being made to run more and more quietly.
Rev engine sounds like sheet metal tearing.
Next would have to be the fan for alignment.
The normal diesel engine knocking is like a drummer hitting solid blocks of metal in regular timing.
Also with the engine off try tapping the exhaust components with a hammer or screw driver to hear if anything sounds loose.
If it s the exhaust you can usually tell by having someone else in the drivers seat to rev the engine a bit while you listen with head down near the pavement at the side of the car not the front or back of course.
This noise is usually heard when you drive your car change gear and accelerate.
Infact if you put your ear on the front fender.
Finally make sure you have all of the sheet metal screws tight.
Youd swear there was a lose bolt or nut.
Here are the 5 most common engine noises coming from the engines and their possible causes.
There is a rattle sound like loose sheet metal riding over top of normal engine blat and generator whine and i haven t found any loose parts yet.
Could be glazed and slipping.
The popping noise tells you something isn t.
Sounds like it s coming from under the passenger side of the dashboard.
When you step on the gas the engine bogs down or takes a second to respond.
Theres another sound that sounds like a peice of sheet metal fender what have you rattling around when i rev the engine up.
This thing hits all the right notes for an engine startup there s so much of that burbling anticipation then it starts to sound like the engine is about to go demonic and tear itself to shreds.
When i rev the engine there is a lag of one or.
It s a whirring sound that sounds like a cricket chirping except the sound is.
If necessary i can make a video of the sound tomorrow.
I ve heard it a couple times before but now it does it every time i start the engine and about half of the time that i accelerate from a stop.
The problem may occur when the engine is hot or cold or when you are low on fuel.
Sheet metal of different sizes can be bent an innumerable amount of ways at different locations to achieve desired part geometries.
You may notice a general lack of power.
This thing sounds like it is beating itself apart.
Tom willmon near mountainair mid new mexico usa net tamer v 1 12 0 registered.
The knocking is caused by the combustion explosion.
The sound seems as if something inside the engine is knocking hard against the engine.
One of the most important considerations in sheet metal manufacture is the condition of the sheet metal s edges particularly with regard to the part after manufacture.