Hello all,

I have an 83 300SD.

1. The engine produces some smoke. How much is bad? The engine has 192K miles. Should I consider having it rebuilt/overhauled?

2. In the past few weeks, the vibration at low RPM has increased a lot. Vibration vanishes at RPMs greater than 1500. It's very bad between 500 and 1500 RPM.

3. The oil pressure is max (3 bar) at just after I start, but it drops to around 1.75 at idle after running for a while. Is this normal?

4. Idling is not smooth. It seems very noisy and sounds like cheap diesel equipment.

5. Engine shakes at idle (I ran at idle with the hood up). How much is normal? I don't remember my old gasoline car's engine shaking.

6. I am most interested in getting the vibration problem solved. Could all these observations be related to each other.

7. Do you guys have recommendations for good independent Mercedes service shops in and around Palo Alto (Mountain View, Sunnyvale, San Jose etc).

Thanks all!
Ranga

How much smoke, and what is the color? Diesels do smoke some. If they don't smoke, then the aren't running in most cases. Even my 2005 TDI smokes a wee bit. It's CC traps most of the smoke particles.

As far as vibration, sounds like the engine mounts and shocks are shot. Replace those along with the tranny mount. Makes a world of difference. Mine was the same way, but I had a torn mount, and one shock was broken, the other had no rubber parts.

Mounts are about $20 each on this site, you will also need the shock mounting kits (rubber pieces), and the shocks (about $50 each). The tranny mound runs about $30.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Thank you for your reply! I will take a look at the mounts.

The smoke is black.

Is there an easy test I can do to figure out whether the problem is a rich fuel mix entering the engine or something wrong inside the engine itself?

Thanks!
Ranga

Have you checked the valve clearances lately? Changed the fuel filters? Run a can of Purge or Seafoam through? Is the Alda cap on or off?

It all sounds like a normal old engine. Nothing serious, yet.

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Paul
2004 E500 4matic; 72,000mi

Do you live in PA? Me too! There is a place near downtown, called DM motors. He works on Porsche's usually, but I think he will work on benz's too. I used to work across the street from him at an independent Mercedes garage (Star Motors) but that has been gone for years...

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1978 240D 4-speed converted to 5-cylinder turbo, Kevlar clutch, 2.88 rear end, nardi classico wheel, H&R springs.

the 5 cylinders always shake a little. they even had to put engine shocks on them, go figure!
check valve clearance, engine mounts, injectors (have them tested at a diesel shop), compression of the cylinders...
you can check the mounts visually. are they torn to bits, does the metal bit dance around in them= worn. your engine shocks can be bad too. fuel filters you should change straight away anyway when getting a benz without history. is the fuel old maybe? injectors you can check somewhat, by whilst running the car on idle 'cracking' the fuel lines. twist the nut that's holding the line down on the injector until diesel comes spitting out. the cylinder or injector that doesn't make a big difference in idling when doing that has a problem, hopefully only with valve clearance.

Here is where you need to look.

ShopForum > General Discussion > Good MB Shops
California:
http://www.peachparts.com/shopforum/california/




Have a great day.

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1985 300SD
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