Booming Noise From Diesel Engine

[ISO2015]

Two days back I happened to drive 2014 Safari Storme. To my surprise there was loud boom (low frequency sound) in the cabin when engine is put on load at particular RPM band.

I had driven new Safari Storme before and this type of engine noise was not there. I really wants to know what causes this type of booming noise from old diesel engine?

 

[VISHNUCARCRAZY]

I am not sure,but check with turbo setup.

 

[Suryaputhra]

Two days back I happened to drive 2014 Safari Storme. To my surprise there was loud boom (low frequency sound) in the cabin when engine is put on load at particular RPM band.

I had driven new Safari Storme before and this type of engine noise was not there. I really wants to know what causes this type of booming noise from old diesel engine?

Is this happened on highway drive or in the city, at what speed and rpm you noticed it, how frequent it is.

-suryaputhra

 

[vikyjoshi]

Oh this is what is called the "Sonic Boom".
Well jokes apart, I have felt that on couple of occasions when that booming sound comes in to the cabin and felt that the car was bit sluggish. I probably was on wrong gears and then change of gears the sound dissappears.

 

[pravin1987]

this happens when the right speed is not acheived for the gear. It happens in my safari as the gear ratiois are out of synch. if i am around 2 rpm at 4th gear, when i shift to fifith the revs fall below 1700 which is out of turbo zone. the vechile would resonate, vibrate as if the car is going to fall apart. rev more and then shift. this has been overcomed to a certain extent in strome, but still you need to rev till 2400 rpm and change gears.

 

[ISO2015]

Thank you all for the response. Yes as pointed above this booming noise comes only when engine is put on load. But why it is absent in the new storme? esp. new Varicor- 400 is totally silent in all RPM and engine load.

I fully agree this is due to resonance. But why it happens in old cars?

 

[stingray91]

they changed the gear box synchro types from triangular toothed to verticentric.

 

[ISO2015]

they changed the gear box synchro types from triangular toothed to verticentric.

Thank you for this valuable info.

So is it noise from gear box?

 

[pravin1987]

Thank you all for the response. Yes as pointed above this booming noise comes only when engine is put on load. But why it is absent in the new storme? esp. new Varicor- 400 is totally silent in all RPM and engine load.

I fully agree this is due to resonance. But why it happens in old cars?

It's not the gear box. Older 2.2 and strome had 5 gears and the gear ratio's are different. In the varicor 400, it has 6 gears and gear ratio's are worked to handle the extra 80nm torque and 8 bhp power. further tata has worked on the fly wheel to aid city drivablity at low to medium speeds.

 

[ISO2015]

It's not the gear box. Older 2.2 and strome had 5 gears and the gear ratio's are different. In the varicor 400, it has 6 gears and gear ratio's are worked to handle the extra 80nm torque and 8 bhp power. further tata has worked on the fly wheel to aid city drivablity at low to medium speeds.

So what could be cause booming or low frequency humming noise?

I remember it was absent in the new pre facelift storme when I took my first test drive in 2013.

Now the storme I drove recently was 2014 (pre facelift).

It is related to engine wear out? I hate this noise. It should not happen to me if I purchase new storme.

Interesting link I found on the net

http://www.partinfo.co.uk/files/LuK 0032.pdf

 

[pravin1987]

You need not worry about engine wear out issues or anything major.

It happens when you are not in the right gear for the speed. In my dicor 2.2, it happens when i lug the engine. not maintaining the right speed for the gear.

Just you need to rev more before shfiting gears to avoid the revs falling below. This is not a major issue. My freind owns a strome 2013.the low frequnecy hum comes at some time and disappear. on further driving i found that when the engine is new thi noise was prominent and when i drove the recently this noise is absent. the car has done more kms.

whereeas in the varicor 400, this is absent as i stated earlier.