http://www.peachparts.com/shopforum/showthread.php?t=266020


So, some have suggested that the noise that I have (one knock for every engine revolution) may be coming from the vacuum pump.

This suggestion would be consistent with where I think it's coming from (as diagnosed with a crude HF stethoscope).

Is there a way to know for sure if the pump knocks without going through rebuilding the pump? I mean, what if its not the pump at all? (I know, I know, then I have a nice rebuilt pump and one more thing eliminated )) but really?

If it's NOT the pump, then you have the knowledge and peace of mind that you have prevented a near-future failure...given how old the pump is already, it's only a matter of time. Just consider it preventative maintenance.

If it IS the pump, then consider yourself fortunate for catching it before it dissintegrated and did some SERIOUS damage.

As for knowing for sure if it's the pump or not....dunno. But if you have narrowed the noise down to the actual pump area, then that's your best bet.

Just rebuilt my own pump about 2 weeks ago. One of the easier jobs I've done on the car. In my case, the vacuum failure was due to the external check valve falling apart. Even though I found that, I went ahead and rebuilt it anyway....and installed a new valve.

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

Vacuum Pump Rebuild Thread
http://www.peachparts.com/shopforum/showthread.php?p=1927867

"Hen's tooth" 1985 300D vacuum filter dark black
http://www.peachparts.com/shopforum/showthread.php?p=1265296

OM603: Vacuum pump explosion, bearing intact! Injection Pump Timing device wrecked
http://www.peachparts.com/shopforum/showthread.php?t=231260





Have a great day.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/

Where do you get a HIGH quality bearing for the pump?? I get some bearings from a place called Boca Bearings for my model engines. Would these be Ok??

Robert

for Mercedes.

You want the rebuild kit with the Mercedes part number,only
[don't try to source the bearings aftermarket...'Just asking for trouble]
(If it's re-buildable)
[The OM 60X.XXX pumps are not re-buildable. 'Just replace]

__________________
'84 300SD sold
124.128

You don't, they will not work.
The multi million dollar R&D has been done on the repair kit parts..
http://catalog.mercedesshop.com/item.wws?sku=W0133-1600004

It is not difficult to find a good used vacuum pump..

Thanks for posting these. I was looking for some vacuum pump threads the other day!

__________________
AJ

1985 300D (SOLD)

[QUOTE=whunter;2357684]You don't, they will not work.
The multi million dollar R&D has been done on the repair kit parts..
http://catalog.mercedesshop.com/item.wws?sku=W0133-1600004

Google Boca Bearings - They have the highest quality bearings in the world, for a price. They also have stainless and ceramic for model turbine engines that turn 250k + . I think that they can supply a bearing from the original manufacturer and not India or China.

Just verifying that a 602 vacuum pump is not rebuildable. -Thanks

__________________
1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png

Note: We are speaking of the OM617 diesel engine..

I understand.
It is still not possible.
Mercedes Benz never released any specification data on the vacuum pump.
There are aerospace, automotive, and other engineers/designers around the world who have tried to reverse engineer the vacuum pump for a cheap fix.
The only result is another engine going to the salvage yard.
The design must tolerate the most extreme abuse, hammering, bouncing, harmonic oscillation/vibration, dirty/thick/thin/substandard oil, dust/dirt (vacuum pump atmospheric vent is inside the crankcase area above thrust rod/bearing).
The original bearing typically survives a minimum of 350,000 - 500,000 miles.
IMO, the vacuum pump valves and piston seal rings are the weakest point in the design, needing to be replaced every 200,000 - 280,000 miles for maximum performance...


FYI: IMO, the OM615, OM616, vacuum pump valves and rubber diaphragm are the weakest point in the design...

There where issues with the OM60x.xxx vacuum pumps dropping bearings into the timing chain (breaking the chain at speed)...
The vacuum pump was re-designed six times...
No rebuild/repair kit was authorized = MB design/engineering developed one, rumor claims seven out of every ten rebuilds in the R&D laboratory failed catastrophically in testing, on all six designs/revisions.

MB never released any data, and is vicious protecting their copyright/patent.

A new vacuum pump is roughly $400.00

A new engine is between (DIY) $8,000.00 and (dealer installed) $12,000.00

This is a case where saving a few dollars will generally junk the car..

Do you recommend removing a vacuum pump for a visual inspection at any point in its operational life? I have 140k on my vacuum pump, not sure if the original owner ever changed it.

__________________
1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png

Replace it, if you are keeping the car long term...

I need your VIN# to lookup the correct part#, as there is an engine design split in 1993..

PM sent.

__________________
1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png