Hi everyone I am trying to diagnose the following problem and need some help.

1983 300SD. Had some nailing at low speeds (first gear only). I took all of the injectors out and soaked them in gumout overnight and replaced them. I did my first valve adjustment (was easier than I thought). The timing chain was not streached more than 2 degrees (286,000 miles). The valves had not been adjusted for at least 100,000 miles and were so tight that I could not fit anything through them.

The car starts up much quicker and idles better however I still have the nailing sound at low speeds and alot of strange clanking coming from the front of the engine at idle. I took it out for a test drive and at one point there was a loud thumping sound for a few seconds that went away when I reached 10 or 15 mph.

I am reading all of the posts and I am getting confused with the harmonic damper, spun bearings, cracked crankshaft or just new injectors. How do I eliminate these to find out what is wrong. Could a bad injector cause this? I would hate to go out and spend $300 to find out I did not need them.

Aloso can I do any bottom engine work without removong the engine if this is needed?

In the past, someone took their laptop out to their car, recorded the engine, and then posted the sound to the forum. It might be helpful in your case if you could do that. It would be interesting to see what diagnostic possibilities arise from a sound over the internet.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

That would be a great idea, unfrtunatly I do not have the capabilities to do it. So what do I do now?

You might be able to narrow it down with a mechanic's stethescope

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Please explain the procedure. What am I listening for? how do I reconize what sounds like a problem?