93 300D 2.5T.

Driving home tonight. Let up on accelerator and it downshifted sounded like someone hit the tranny with a hammer. Thought I lost a transmission or rear gear. Drove fine in a given gear. Upshifting also sounded like a hammer. No where to turn off, so I kept driving. Drove further and NO BRAKES! Thought I ripped something up, lost fluid, heart pounding at this point. No sound or smell while driving and no where to get off the road, only a couple miles from home in the country at this point. Limped home, shut off the key and the motor kept running! Shut off with the manual lever on the IP. Brakes felt like basically no power boost. I wouldn't have wanted to be going 70 mph and had this problem.

My assumption is all these things use vaccum in common. No obvious parts laying under the car or fluid. Does vaccum sound right? If so, where do I start to diagnose further? Is this a pump or line most likely and what is common to all these things? Any pics, suggestions, diagrams???

Thanks much.

Your vac pump might have failed. I would not run the motor again until you confirm this....if it dumped bearings into the crank case it can destroy the engine.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Some reading:
http://www.peachparts.com/shopforum/showthread.php?t=235927
http://www.peachparts.com/shopforum/showthread.php?t=295124
http://www.peachparts.com/shopforum/showthread.php?t=231260


Good luck.
google search http://www.google.com/search?q=vacuum+pump+site%3Apeachparts.com

also try this in google search: vacuum pump site:peachparts.com

some cool pictures: http://www.google.com/images?q=vacuum+pump+site:peachparts.com

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92 300D 2.5L OM602 OBK #59

Oh goodie, this sounds wonderful! I was hoping for some electrical pump or something that had gone bad. Well, I understand the situation now. Forutnately, the motor was sounding fine when I got home and parked it. Doesn't seem I destroyed it but now I am worried about how much shrapnel might be floating around. I won't be starting the motor until I verify the pump and timer situation.

The car has 128K on it now. Do these pumps fail in that mileage range typically? Just wondering how typical this is or am I just lucky again!

Some things are coming together in my head now. I've had a ticking or clicking noise in the motor for a few months. I honestly thought it was just injector slap. I wasn't too concerned to replace as it ran fine and there didn't seem to be any risks. Perhaps that was this vacuum pump starting to go, I don't know.

This has been a whirlwind affair. I thought I lost my transmission, then thought I lost an axle or something to cause brake loss, then thought oh good it's just a vacuum pump, then oh s*&t this is a mechanical pump on the motor. I have two of these old MB's, I guess I need 3 to keep 2 running at any given time.

Man thats strange please keep us informed on this matter.

__________________
1999 w140, quit voting to old, and to old to fight, a god damned veteran

Could also be as simple as a broken main vacuum line or a failed brake booster.

It's also an argument in favor of a vacuum gauge or at least a warning sign which states that when the transmission starts shifting hard, be prepared for no power brakes.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Ill bet its your vacuum pump.

Safe: Visual inspection of vacuum lines for breaks or disconnections. Remove the Vacuum Pump and inspect the drive mechanism and inspect the Check Valve.

Not as safe: Run Engine and check the Vacuum.

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84 300D, 82 Volvo 244Gl Diesel

I'll definitely pull the VP and take a look to make sure a broken pump is the problem. I don't see any obvious broken vacuum lines (like the big one going to the brake booster) but that line looks very aged and brittle as do a host of others so who knows. Definitely no sounds coming from motor so I don't think it's picked up a ball bearing in the timing chain at this point. Maybe the VP isn't gone but I'm not going to turn the key until I see for myself and that looks fairly easy to get at to take a peek. My biggest concern is how the hell am I going to clean any metal debris out of the system if what I think has happened has actually happened?

Before I pulled the vacuum pump, I'd at least put a Mity Vac on the various parts of the system and see if I could pull a vacuum on it, starting with the brake booster since it consumes a lot of vacuum. If it's got a hole in it, no reason to pull the vacuum pump.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I have cleaned plugged oil pickup screens by draining oil out.Then filling crankcase with two gals.or diesel.Shaking engine good draining,repeat with diesel.Fill with oil,and turn engine by hand 10 complete turns.Then fire her up.

__________________
1999 w140, quit voting to old, and to old to fight, a god damned veteran

There is a side-sump on the OM603.96x engines, can be removed so that you can inspect inside the pan and possibly clean it with a magnet etc.

__________________

Gone to the dark side

- Jeff

Not sure the OM602 has the side sump.

__________________

"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

Yes you do, he is talking about the oil level sensor. That is a good idea, it is on the driverside on the oil pan. Drain all oil then take sensor off and if there is any metal you should be able to get it with a magnet.

Update:

It is definitely a VP failure. I pulled the pump this morning. Both bearings on each side of the roller that rides the timer lobes have let go. I don't think it is too bad at this point but I have some issues to think and work through.

The timer lobes look good. No marking or obvious destruction. I am a little surprised about that. It looks OK so I am thinking I don't need to pull that. Partly because I have no idea how the hell to get that thing out of there. Does the chain come off without some major tear down beyond pulling the pump????

I found one of the bearing centers laying just below the timer gear. Got that. I now have all the pieces for the bearing housing accounted for. One of the cast pieces that holds the bearings in place is beat to hell, but it looks like its warn down point being there are not chunks missing. So there is some metal fines in the system.

I dropped the oil and pulled the side off the pan (it does have an access panel on the passenger side. With a pen magnet, I have found 7 balls. I think from what I read, there should be 6 in each bearing so a total of 12. Thus as of lunchtime, I am missing another 5 ball bearings.

I am getting a big magnet and going to run it over the outside of the pan and try to see if I can find more balls.

Here is the big question: If I don't find the others - then what?? They gotta be in there somewhere.

What a pain in the a**!