When you hear TAPPING, rattling, knocking.

Before you freak out, thinking critical damage, injectors, rods, injection pump, engine failure, etc...

Please look at the 'Tensioner assembly' for the serpentine belt.

This Tensioner assembly and the shock absorber are COMMON FAILURE items.

The shock absorber has been superseded many times = if you don't have the current level part 99.999% odds the old one is junk.

Attached are pictures of destruction caused by a bad shock absorber.


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1985 300SD
1983 300D
1984 190D
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Indeed. I understand the mounting boss can rip out of the timing cover, making for an expensive repair.

Jeremy

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"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

I think Roy can answer this best, Some mechanics here in Houston and a member of this board said that bad engine mounts can cause the shock to overwork itself, HOW??

The entire thing is bolted to the engine, so it shouldnt matter if the engine were sitting sideways, right side up, etc. btw - I got hold of a NOS item for a 350 SD. Strangely the part no on it is the same as my old one

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Just been there and done that. New shock/damper, new spring, new idler pulley, new belt. I hear that some have used an aftermarket arm for $27 from Ferbi ? I got mine from supplier says German Made for $75.
Good luck

BTW, I can't see how a bad motor mount would have anything to do with the failure of this part. That just doesn't make any sense.

Roy, what's your experience with MB label vs aftermarket (including Febi) damper longevity? I heard MB label lasts proportionately longer based on price vs aftermarket. Also, it seems that across all brands damping ability far exceeds the life of the end bushings.

Sixto
87 300D^2

I probably read it here somewhere, or maybe in the instructions that came with a new MB brand shock, but you are supposed to work the shock in and out all the way a few times before installing it.

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

Yep, that is what the shop manual recommends. Another item not mentioned relates to the alternator pulley. I have a 96E300d, and the alternator came with a "clutch pulley", which I never heard of. That pulley compensates for the different forces the engine produces during compression. I purchased a new alternator, that came with a regular pulley, and when installed, the shock was working overtime and the belt was vibrating more than usual. Changed out the alternator pulley with the old one, and everything was back to normal, no vibrations whatsoever.

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96 E300d

The really odd bit is that the same engine is used in the W124 chassis and MB gave a solid pulley on it, its a Bosch 100 or 120A (need to check) alternator and can really lug down the engine. I believe that the last version with clutched pulley should be used even on the W124. The old VW 1.9 diesel had crank timing pulley failures due to a solid pulley design on the alternator.

My posting is because I got hold of a NOS belt shock, its part no. is 604 200 01 14 - which is an old part number and this same was installed on my engine too as OE - the bushings on it went bad, they are loose hence it rattled. Both old and new shock work the exact same way, its very very hard to push in but "relatively" quite easy to pull out. I put in the new item and it also rattles - The rattle goes away if I lever the tensioner arm upwards.

The tensioner quadrant is straight, moves smoothly, the pulley on it rotates smoothly - the spring is intact but I still have rattle,, grrrr - I removed the fan, belt and w/p pulley to access the lower bolt. Is it that the new part no. is hard to move in both directions as to provide a higher level of damping or is it just that the alternator pulley needs to be swapped for a clutch type, which would be my next step.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

That "rattle" was something I left out of my other post. When I used the pulley on the new alternator, I got a rattle at idle that I did not have with my old alternator. Put on the old alternator clutch pulley, and the rattle was no longer there.

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96 E300d

I could be wrong but it's my understand that this design of a shock/damper should have equal resistance when moved in either direction like a steering damper.

I had exactly this problem and when the bushings wore out on the tensioner arm it managed to back out the pin/bolt that holds it in and the whole thing came off while I was driving. Ordered the arm, shock, pin, and belt from PeachParts and they all appear to be OEM parts. So far so good. The EPC shows an o-ring that looks like it goes between the arm and the washer/spacer. The old arm doesn't seem to have an o-ring and there is no groove for an o-ring in the new one. Does anyone know if that is a design change or does the o-ring just get sandwiched between the washer and the tensioner arm?

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'82 300D - Light Ivory, 2nd Owner (Back in the wind April 2013!)

'95 E300D - White, grey interior. (Suffering from stuck/broken glow plugs)

Deuteronomy 22:4-
"Thou shalt not see thy brother's ass or his ox fall down by the way, and hide thyself from them: thou shalt surely help him to lift them up again."

that isn't an o-ring - its a hard plastic washer. When I replaced the whole assembly in January, I decided that the plastic washer was actually a dust cover that kept dust from reaching the threads of the pivot pin.

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

None of the usual on-line parts suppliers have that part number (6062020060) so I'm guessing not a lot of people order it. Do you think it's needed? My old one doesn't appear to have it but then again my old one failed.

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'82 300D - Light Ivory, 2nd Owner (Back in the wind April 2013!)

'95 E300D - White, grey interior. (Suffering from stuck/broken glow plugs)

Deuteronomy 22:4-
"Thou shalt not see thy brother's ass or his ox fall down by the way, and hide thyself from them: thou shalt surely help him to lift them up again."

I think that the plastic washer is not needed. There are much bigger fish to fry.

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

Just bought a new lever from the dealer 2 weeks ago, $111 w/discount.

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