Well....
 

Dave,

I've stumbled upon this reference to a "modification" in the VP as of Dec.1994 for "Cost reasons".
(While searching for R+R instructions for the Vacuum Pump)
[Effected engine is as listed ...BUT,we all know how engineers and bean
counters love to cross the entire engine line with "Standardizations".]

Man,would I just LOVE to know what kinda CHEAP HACK JOB was instituted!!!



'Think this could have any thing to do with your published failure rate?
'OR your more recent "Brush with Mechanical Death" VP wise?

EDIT:
Timing Chain/Vacuum Pump OM 60X.XXX
grober, over on MB Club Forum UK found this for me in reply to a question about
Vacuum Pump Modifications.

"There is an oblique mention of "installation of vane cell pump (BARLUK)" at one point in the text which is maybe the modification you are talking about?"

edit - more details here:http://mbca.cartama.net/showthread.php?t=22830

#
07.1-1843

Well shoot, I really don't know! The newer pumps are visibly improved compared to the original 86/87 pumps. I would love to find out what the change was in 1994, but we may never know...

:(

Brief update:

6500 miles later, at oil change time (300kmi), I pulled the side sump off the oil pan to inspect for any leftover debris. I had a large, very powerful magnet attached to the drain plug (externally) during these 6500 miles to try and keep any metallic bits away from the oil pump pickup.

While there were a few tiny bits in there (near the drain plug), it was basically nothing compared to the original pile of shrapnel that I extracted originally. Anyway, I cleaned out the few pieces with a magnet, put the side sump back on with a new gasket, and I'm considering the job completed.

:boat:

That guy was pretty lucky. :o But he had the old, original pump... the old style has the twelve balls and plastic cage. See photos below:

http://www.w124performance.com/image...p_failing1.jpg

http://www.w124performance.com/image...p_failing2.jpg


This is what the new style looks like:
http://www.w124performance.com/image.../vac_pump3.jpg

:1eye:

Dave,

So, is the progression as follows:

1) Open bearing with 12 balls
2) Open bearing wity 6 balls.
3) Sealed bearing

????????:confused:

I'm not 100% sure, but I believe it is:

1) Two open bearings with 6 balls each (12 balls total)
2) Single sealed bearing

:euro:

Are w123 pumps the same as 124's?

No, entirely different. The 123 (OM617) pumps are about 3 times larger and can be rebuilt, and I've yet to hear of one of those pumps falling apart internally.

:nuke:

Thanks for the clarification. On your original comments, I took the old style to mean 12 balls in each bearing. I now see that the number of balls is (likely) the same (six).........the new style is sealed.

Whew!
 

Thanks! Dave.

(I'd just INCORRECTLY assumed that with a '93 the OP had the Newer style
pump with the closed race.)

I have a rebuilt Pierburg. It has the plastic encased bearings. I don't know the build date. There was a post somewhere that had the progression of part numbers for the Pierburg. I think mine ends in 77.

My timing device is of the old style. It has a little galling but I'm tapped out now for replacement parts on the car.

I had one of the "later" W123, piston type pumps come apart due too lateral movement of the timing device caused by a worn bushing. Caught it before it destroyed the engine.

In a past thread I ask people what they thought caused the VP failure.

http://www.peachparts.com/shopforum/diesel-discussion/204187-what-particular-causes-vacuum-pump-failure.html?highlight=Vacuum+Pump

Another Thread concerning Timing Chain breakage;some of the member felt the Vacuum Pump had failed a part fell into the timing Chain. I believe most 617 engines.
http://www.peachparts.com/shopforum/diesel-discussion/203364-who-has-knows-someone-has-experienced-timing-chain-breakage-failure.html?highlight=timing+chain+failure

Years ago I had a W115 VP that internally grenaded, but mercifully it didn't take out the engine.

If anyone's still listening, could you tell me if this pump is Ok. It's not the pierburg as far as I can tell, but maybe it is just unbranded or something. I can't tell, looks the same as the new pumps to me (for a 92 300D 2.5 which had the new style)

http://i7.ebayimg.com/06/i/001/1f/8c/fe34_1.JPG

It's part #0002303165, I just don't know if it's decent quality. I've only seen Hella and Pierburg as manufacturers, and this one doesn't have the sticker they have (both look identical btw and they both have the PIerburg sticker on them. Weird).

THis one comes wtih the gasket, and it is the dam style gasket right?