87 300d 197k

I've owned this car for about 20,000 miles and it has always made a tapping noise if started cold and then idled. It also makes the noise (with greater frequency--more taps per revolution) when started cold, shut down, and started cold a few minutes later.

It goes away if I drive hard on the highway for a good 20 minutes. Even better is climbing a steep hill at low speed--all the noise is gone and it purrs beautifully.

I've talked to some people and some think it's a lifter, but some think it's an injector. Others have no idea but have suggested synthetic oil. The crankcase is full of Mobil 1 10w30 presently. I eased the engine onto synthetic with a 3/8 portion of synthetic, then 1/2, then 5/8, and full synthetic is planned for the next oil change (in a week or so). I started phasing in
the Mobil 1 at 191k.

If it is a lifter, I have a can of B-12 Chem Tool by Berryman Products. It has toluene and benzene and some pretty harsh chemicals in it, so I'd like to know if it is likely to do harm if I mix a little in before I suck the oil out with my Topsider. (It says to pull the oil pan but logistics dictate that I cannot do that.)

When the lifters/injectors/whatever have been ticking and clacking for a long time during a drive in town, I get a large amount of smoke if I floor the accelerator. The smoke eventually clears and I get a little more spunk from the engine than before.

I have recorded the sounds in two MP3 files available at
http://63.248.251.80/~jrd/noise1.mp3 http://63.248.251.80/~jrd/noise2.mp3

I look forward to hearing from fellow diesel owners!

Sincerely,

Justin

------------------
Justin Dobbs (jrd@jrd.com)

The sound that a lifter makes is distinctly different than the sound of an injector with a faulty pattern. Have someone that knows the cars to listen.

------------------
Benzmac:
Donnie Drummonds
300E
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM
OWNER OF MB AUTOWERKS .COM