So i have a 240d and my 300tdt. I have noticed my 240d is MUCH louder than my 300tdt. Is this normal? Is the OM616 just an inherently louder engine?

I believe it is mainly the turbo. Turbochargers silence much of the exhaust noise.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The 4 cylinder also has shorter gearing, so the engine turns faster for a given road speed.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

I would say especially on the highway there is a noticeable difference. Or that has been my experience anyways. Some 240ds also seem louder than others.

My 78' 240D was significantly louder than my 85' 300TD. I think engine RPM due to gearing and variances in insulation were the two main factors. Both were in nice condition.

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

The 240D has a 3:69 Differential.
The 300D NA has a 3:46 Differential
The 300D turbo uses a 3:07 or a 2:88 Differential

The higher the Differential number, the more rev`s of the engine in high gear on the highway.
That is why a 240D will be a bit louder.

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Like your expression of a bit louder. I always thought the 240d at high speed was developed originally for the hearing impaired. Do not leave home on a long highway journey without a good audio system and a tailwind.

Really though with age there is a noticeable difference between examples. First the easy stuff. Get your fuel pressure where it should be as a proper power balance quiets the engine. Also may save the first cylinders rod bearing leaving the engine over time as well.

As a side issue you also want the little more power it can give you if the fuel pressure is too low. The power balance logically gets even worse at high speeds with low fuel pressure. This in itself increases noise.

Next go over the engine and transmission mounts for condition.

I have never played with how much help a good hood pad is over none. All my cars still have them but many out there do not.

The 240d was designed for cruising along at about 50 mph and that is not realistic today. It will sustain what is needed today pretty much but things have to be in good condition to keep the noise at a minumin.

I still keep feeling for fifth gear but it just is not there. Changing the rear end ratio a little will help but still not enough as there is not enough power to pull a much lower ratio that is really needed.

Are the exhaust systems exactly alike to begin with ? The 240 is a cheaper car typically... and I do not know if the specs on the mufflers/ resonaters (?) are the same...

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/showthread.php?t=156207&highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

The 240 system is similar but of smaller diameter pipe.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.