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80 280SL, 85 300SD, 87 300TD, 90 300TE 4Matic, 90 300D 2.5 Turbo, 92 300D 2.5 Turbo, 92 300TE 4Mat
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Discussion Starter #1
My 1992 300D 2.5 Turbo at start-up started making a horrendous clatter. I shut it down and looked for anything amiss. After seeing no problems I tentatively restarted it. It ran about a minute (without the A/C compressor clutch engaged) and then acted up again, just as bad as the first time. The noise sounded like it was coming from the accessory belt area, maybe the power steering pump or A/C compressor. I shut it down standing there using the fuel distributor shut off. Still nothing was apparent, until I noticed oodles of clean (without oil, etc.) aluminum shaving under the belt area. There were also shavings on the sway bar at the middle of the car. I looked closely at the power steering pump and alternator but still saw no problem. The fan does not hit anything. The accessory belt is still taught.

My thoughts are it could possibly be the A/C compressor, water pump, fan clutch, belt tensioner, or something that had fallen behind the crank pulley. There is no air pump as it is a diesel.

I had recently serviced the A/C, to include removal and flushing of the compressor.

Has anyone encountered this before?


 

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Cruise Control
'87 300TD/'90 300D/'94 Quattro/'89 Vanagon TDI/'01 EV Weekender VR6
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52,233 Posts
The lack of oil is what's throwing me here. Did something foreign get trapped and systematically shaved by one of the pulleys?
 

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80 280SL, 85 300SD, 87 300TD, 90 300TE 4Matic, 90 300D 2.5 Turbo, 92 300D 2.5 Turbo, 92 300TE 4Mat
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Discussion Starter #3
Most likely. Given the cleanness of the cuts, it seems more likely the shaving are from something that was turning, as opposed to the turning item cutting stationary stock.
 

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2008 E350 4M, 2016 Audi Allroad, 2019 Audi Q5
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5,445 Posts
Most likely. Given the cleanness of the cuts, it seems more likely the shaving are from something that was turning, as opposed to the turning item cutting stationary stock.
Agreed.

Check fan clutch bearing bracket first. If the fan does not spin perfectly center, the bearing needs to be replacing. Just view from above and look down. It should be obvious.
 

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W124 Moderator
86 190E 2.3L 16V, 2 95 320TE's, 02 S500
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12,744 Posts
My thoughts, based on the area you found the shaving is the compressor clutch. Have you run the car with the HVAC in EC or off mode? Sounds?

Jayare

Sent from my DROID2 using AutoGuide.Com Free App
 

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80 280SL, 85 300SD, 87 300TD, 90 300TE 4Matic, 90 300D 2.5 Turbo, 92 300D 2.5 Turbo, 92 300TE 4Mat
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Discussion Starter #6
I just had enough time this evening before dark to take some pictures of the front of the engine in the hopes of seeing something amiss.

Areas, such as around the A/C compressor and power steering pump look clear, to include in the compressor clutch.





All pulleys look and feel straight and the belt is tight.



The alternator looks okay.



It soon became evident the problem is centered in the lower main crank pulley area; specifically to the rear and right side of it. All shavings appear in that area.



It was hard getting a good shot laying on the oil stained asphault street. So I took a bunch of pictures with the hope at least one would shed some light on the problem.





You can see some scraping and waste splatter in this picture, so I knew I was getting close. Just not enough yet what was causing the problem yet.



Then this little gem showed up, but just barely. It is really too dark to tell anything as taken or when veiwed on the camera screen.



However, enlarging it on my 24" desktop screen revealed what appears to be a bolt wedged between the timing chain cover and the main crack pulley.



So, now I know what is causing the noise/shavings. The next question that I must answer is where did the bolt come from? I liberated some of GSXR’s reference pictures from his 124performance.com website for comparison with those I took to see if I could notice any critical bolts missing (e.g. water pump housing, timing mark support bracket), or if I can safely assume the bolt is an otherwise harmless stray. Hopefully it is the latter.








In any event, it does not appear that it is fatal.
 

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'87 300TD/'90 300D/'94 Quattro/'89 Vanagon TDI/'01 EV Weekender VR6
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That's a weird one. I'd pull that harmonic balancer off of there and see where it leads you.
 

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80 280SL, 85 300SD, 87 300TD, 90 300TE 4Matic, 90 300D 2.5 Turbo, 92 300D 2.5 Turbo, 92 300TE 4Mat
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Discussion Starter #8
I'm thinking now I've got to do just that to at least make sure there are no cracks starting in the timing chain cover.
 

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E320/E250 Bluetec Ford F350 6.7l
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That looks like fan clutch shaving and the picture doesn't look right, although that could be the angle.
Have seen those before, but not that big. Try to turn fan blades on stopped engine.
 

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W124
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"I had recently serviced the A/C, to include removal and flushing of the compressor."

Every bolt from that procedure accounted for?
 

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80 280SL, 85 300SD, 87 300TD, 90 300TE 4Matic, 90 300D 2.5 Turbo, 92 300D 2.5 Turbo, 92 300TE 4Mat
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Discussion Starter #11
I spent some time working on the errant bolt yesterday. Here is a better shot of it; although blurrier.



It is a 10mm, about 1.25" long with an allen head.

With a little work I got it unstuck. It was then resting over the slightly smaller gap opening between the oil pan/timing chain cover and the dampener. I used a piece of 12 ga. copper wire to fish it over to the side of the front oil pan so I could get it the rest of the way out over the oil pan bolt setting.

In the process of working it over a I inadvertently knocked it towards the middle front of the oil pan, directly under the crank. From there I lost sight of it - I mean forever! I spent the next 4 hours removing progressively more parts and fishing around for that little fucking bolt!!! It just up and disappeared. I even started the engine again a couple of times to see if it would shake loose - no luck.

I was just barely unable to see the bottom center of the timing chain cover above the front center of the oil pan, and thus could not be assured the bolt had stuck itself up in some grease, just waiting to drop down again and wreak move damage at a most inopportune time. I got a bunch of brake cleaner and blew out the grease, but still no luck. I got out my fiber optic camera (which I don't like to get greasy), but still no luck; although, I was now able to see it was NOT there.

I have no idea where that fucking bolt went, but at least it is not where it can repeat its prior damage. Additional pictures failed to disclose its location.

I was also, able to see that the fucking bolt did not appear to have worked its way loose and was missing from any current setting, such as the timing mark support bracket (from which I suspect it came initially prior to being replaced).

I drove the car about a long block with any problem.

Here are a few more of the sample shots.






 
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