MB diesels getting noisier?

Page may contain affiliate links. Please see terms for details.

iscaboy

Active Member
Joined
May 12, 2010
Messages
604
Location
Devon
Car
W124 E300 D (1991)
As I wafted past a clean silver estate E320 CDI today, then came alongside it at the junction, then wafted down the road when the lights changed (nice day so all windows down) I was struck by how much noisier and more "diesel-ey****" the much newer E320 sounded, and mine is 20 years old with 20 years of wear and tear.

It really was a significant difference, and it minded me of other engines over the years, air cooled bikes to water cooled cars, that went from iron heads to alloy heads and got a lot noisier as a result.

Just me? Just a good W124 vs a bad W211? Or representative?

**** the diesel injection / ignition "knock"
 
I had a E300TD and it was quiet compared to the present CDI. But I'm going to try your 2 stroke trick and see if things quieten down.
 
Damn, it hadn't even occurred to me consciously that it might be the 2T :doh:
 
I had a E300TD and it was quiet compared to the present CDI. But I'm going to try your 2 stroke trick and see if things quieten down.

The 300TDs are unbelievably un derv like inside the car. Dieselman took me out in his and it sounded JUST like my old I6 petrol Beemer. Quite unlike a derv it rev'd cleanly to 5k rpm as well.

I'll report re my E320cdi (V6) which comes tomorrow. From what I gather its no advance on the 300TD economy wise, but a useful 50bhp more (approx 100 ft/lb torque as well. Test wise only at low speed was it every so slightly gruff (it was cold). Other than that a nice smooth fast engine. :thumb:
 
Dieselman would probably explain better but he explained it to me once that it's to do with the amount of fuel injected, the leaner they run (and more efficient) the faster the flamefront so the bigger the knocking noise, so at idle they make more noise per bang than under load, and modern engines are noisier because they use less fuel. Or something.
 
No, by and large modern engines are noisier because they are lighter... for example you could stand next to a Lister CS which is a 1.4 litre single and provided it had a decent exhaust be forgiven for thinking it was a steam engine, but mine had cast iron piston, iron head, 600 lbs of flywheel, ricardo indirect injection chamber... and cuff the bitch on full rack and it went "chufff - CHUFFF - CHUFFF" and so on.

less engine mass = better lbs:bhp ratio and better performance..
 

Users who are viewing this thread

Back
Top Bottom