What's the clacking! (video attached)
 

Got a clacking in the ol' slug (1983 240D)

I've done a diesel purge (twice), replaced the injector nozzle from where the sound seems to be coming from 4th cylinder at the oil cover), adjusted the valves (lifters).

I even just replaced the front left wheel bearings, in case they were clacking... but no, it wasn't them.. (they needed replacing anyway)

So what is the clacking noise in the movie file at www.pauldrayton.com/uploadfiles/clacking.mpg ? (It's a 13 mb video file. A small audio only file is at www.pauldrayton.com/uploadfiles/clacking.wmv for the bandwidth challenged). The sound gets worse when you ride around for a while.

When I had the oil cover off while doing the valves, I noticed the bar that goes across the top, above the camshaft, has some play in it at the far end. But nothing that could clack like it does. I didn't know how tight the chain at the front should be (is that the timing chain?), so I couldn't really check it. The sound doesn't seem to be coming from the front though. I've listened with a piece of wood all around the engine. The only place I have heard it as on the oil cover at cyl 4.

Could this be the famous nailing? I didn't adjust the bozio nozzle I bought - I just stuck it in. I don't have shims to adjust them anyway - still waiting for the stealership to get them from Deutcshland uber alles. If this is a injector issue, then fine, I'll get them adjusted properly.

But it sounds like something moving and perhaps even slapping. Heck, you listen to it and tell me. If a picture is worth a thousand words, then a sound is probably worth about 435 words, so I'll stop typing now.

Some advice would be great. This is my work car and I want it working! :)

Thanks

It has a nice diesel sound to it. Except for that clacking sound. Have you tested compression?

You can get a compression tester at www.harborfreight.com.

danny

FWIW, it does not sound like injector nailing to me, it sounds mechanical. I can't think of anything obvious near the back of the engine. :confused:

That's definately a wierd noise. It sounds hollow and metallic like something hitting the inside of an big empty coffee can. I don't know if it's mechanical or a byproduct of the combustion process. Have you lifted the hard injector lines one at a time to try to isolate the position of the noise?

Don't listent to me, but I think it's just the normal vibration of the engine makes something clack in the engine bay while the whole block moves a little.

Just to rule it out, check the air filter housing to see if it is knocking in its mounts. Mine resonates a loud clack when it is loose. Good luck!

Just to rule it out, check the air filter housing to see if it is knocking in its mounts. Mine resonates a loud clack when it is loose. Good luck!

I was thinking the same thing. Mine had a noise similar to that when I 1st got it. It turned out the air filter bracket had broken.

Not an injector
 

I'll agree with those saying the noise is mechanical. Check for broken air filter mounts or anything else that could be loose or broken that could come in contact with the engine. It's pretty loud, so I'm guessing that it will be something made of thin (sheet?) metal that resonates a lot when the contact happens.

Yeah, it sounds like some thing that is attatched to the engine or in the engine compartment. Check the flex joint off the turbocharger (if equipped)
there might be a bracket loose or something...

Another possibility if your exhaust, maybe the bracket came loose and is rattling. Unlikely but worth a check.

My car sounded like it had a tin can banging around under the hood shortly after I got it, then the water pump started weeping, so I replaced it (original I believe, it had 214k on it! :eek:) and the can sound was gone! :D Just an idea, and thats at the front of the engine but sometimes where the sound is coming from is deceiving.....

Yeah, there are a lot more possibilities if the sound is from the front of the engine, like the vacuum pump that just ate itself on my 617.:mad:

Just watched the video and have to admit that its quite an odd sound....the vision I got when watching/hearing it was of something going "scrape..scrape....tap....clank...." inside the back of the valve cover.

Thats what it sounded like to me....what could do that in there? Is that even possible?? :confused: Then again the sound could be the bottom of the air cleaner banging on the arm it sits on.....but it seemed like its coming from the valve cover....

It sure doesn't sound like an air cleaner bracket to me. It sounds like a loose mechanical part that keeps changing position (maybe rotating), I just don't have a clue what it could be.

Could a loose pre-chamber "ball" make that sound? Just a wild guess.

It is almost impossible to determine the source of this sound over the internet. As mentioned, it sounds like something external to the engine.

Get a piece of hose, about 1.25" diameter or so, and put one end in your ear and the other end at various points around the running engine. The hose amplifies the sound and you'll likely be able to home in on such a sound if you are patient with it. It might be beneficial to have the vehicle on ramps so that you can go underneath it while it's running........but.......be careful.......that fan is no pleasure if you bump into it with the hose.:mad: