Vacuum pump ball bearings fell out. Now what? - PeachParts Mercedes-Benz Forum

jubjub · #1 06-15-2013, 10:01 AM

We were diagnosing a tapping sound and found the vac pump is blown. All 12 ball bearings are gone. The engine still runs fine (I hope) I've looked at a bunch of the vac pump failure threads, but am not sure what to do now? Are all the bearings in the oil pan now? Should I drain the oil and/or drop the pan to see if all 12 bearings are there? Or would they not make it back to the pan?

pwogaman · #2 06-15-2013, 10:16 AM

Yes, drop the pan and get them all. You should account for every last one.

funola · #3 06-15-2013, 10:16 AM

pics? buy some lottery tickets.

LoosBenz · #4 06-15-2013, 10:44 AM

Quote:

Originally Posted by pwogaman

Yes, drop the pan and get them all. You should account for every last one.

^^^What he said. Even one ball bearing in the oil pan can work its way through to the oil pump or timing chain and virtually destroy the engine.

Stevo · #5 06-15-2013, 10:48 AM

Also pull the screen off the bottom of the oil pump and look for balls in there.

Stretch · #6 06-15-2013, 10:50 AM

What's the damage on the follower arm like? Has it made a mess of the timing device?

With any luck you'll find all 12 bearings in the lower pan.

I have my fingers crossed for you.

You also need to check the timing device and the bushing for the intermediate shaft before refitting a repaired or replacement vacuum pump.

Diesel911 · #7 06-15-2013, 01:30 PM

I think what was meant was to check the End Play of the Timer (that connects to the intermediate Shaft).
Also take a good look at that shaft that connects to the Piston up where it goes through the Piston. If the Arm returns too far it can crack the area where it attaches to the Piston. I hope I picked the right thread on that.

Repeat broke new vacuum pump
second vacuum pump, help! on a trip-Toronto - PeachParts Mercedes ShopForum

There is one Person who said they replaced the Bearing with another Bearing. But, I don't recall them saying what bearing they used. I do remember that they made sure they got one with a lot of Ball Bearings inside.

I am also curious. Your 1985 should have had the Vacuum Pump that has the shields that cover the Bearing. There is Metal Washer on each side of the Bearing.

jubjub · #8 06-16-2013, 12:58 PM

Got the oil pan off today. 11 bearings found

I did fine some magnetic metal bits in the pan and what looked like bits of shell of something that was chromed. Could the 12th bearing have been chewed up? So, I guess we have to ask ourselves. Do we feel lucky?

I saw no signs of a metal shield on the bearings. I did find bits of plastic in the oil pan.

Also checked endplay on the 'rollercoaster' I got 0.010"
Go ahead and replace the bushing?

Some pictures. As you can see the rollercoaster started to eat into the arm. We are going to buy a new vac pump. I can't see any damage on the engine side.

Stretch · #9 06-16-2013, 01:13 PM

0.01 inch = 0.254mm

The limits are 0.05mm to 0.012mm (see here for example http://www.peachparts.com/shopforum/3159307-post23.html)

My advice is to change the bushing as well as the pump - at the moment the combined cost of a sealing kit and a new cam follower arm is more than some prices for a complete new pump.

It would be nice to find that last ball bearing...

turbo6bar · #10 06-17-2013, 03:26 PM

Hi, all. This is jubjub's brother and owner of the 85 300D with blown vacuum pump. I will order the new bushing to get timing device endplay back within spec (0.05-0.12mm), and I will buy a new or rebuilt vacuum pump. While I want to find that one last ball bearing, I'm not prepared to pull the engine and start tearing it down. I'm going to gamble on this one (famous last words, I know).

I found a company on eBay selling rebuilt vacuum pump. The one for my car is $250US with an included core charge of $40, so I am at $210 for a rebuilt pump. I emailed the seller to inquire about the bearings used. He simply said they are original type. I pressed him about the construction of the bearing (plastic or metal cage), and he responded that he did not know, and that they have never had a problem with the pumps. Has anyone dealt with bmwmercedesautoparts before? I'd like to save $90 by buying the rebuilt unit.

Regards,
Jurgen

BillGrissom · #11 06-17-2013, 04:12 PM

I would put a magnet in the bottom of the oil pan to hopefully grab the missing ball next time it passes by. You can also try fishing for it with a "small magnet on a flex stick" like Sears sells. You might also consider using an electric vacuum pump. Some VW's have one for their brake booster that might work.

mach4 · #12 06-17-2013, 04:43 PM

Sounds like you're a betting man. I think I'd be inclined to go that route too. I think that there is a pretty good chance that the remaining ball bearing is lodged somewhere safe.

But it would also be a good idea to take steps to prevent it from getting sucked into the oil pump should it find its way into the sump. The pickup looks something like this.

If you were to get some rare earth magnets you can arrange them in the sump to protect the pickup.

If you estimate the position of the pickup (blue) and then arrange the magnets (red) like so...

...you could be pretty much assured that you'd trap any remaining balls as well as any other ferrous materials that might get down to that area and otherwise potentially make it through the screen.

Just a thought.

I think I'd also be inclined to pull the pan at the next oil change and inspect. If the ball is there you can really rest easy, and if not, it's pretty good confirmation that the ball is safely wedged somewhere in the engine.

Chris W. · #13 06-17-2013, 08:06 PM

When my vac pump grenaded, after it was all back together, oil changed, I put a stack-o-magnets on the oil drain plug and drove for about 500 miles. Changed oil again. Collected all but one ball. Been driving for about 150K since then. IMHO? Carry on and don't worry about it. The pan is aluminum on my car, magnets no sticky on there, gotta use drain plug.

Rgds,
Chris W.
'95 E300D, 396K

turbo6bar · #14 08-29-2013, 12:10 PM

It has been a while since I last posted here. I replaced the vacuum pump, and upon starting the car noticed it had a pronounced ticking from the vacuum pump area. Before replacing the pump, I measured the end play of the intermediate shaft and the reading was twice the maximum specification. I believe this excessive end play resulted in failure of the original vacuum pump and left unchecked, will destroy the replacement.

Reading an old thread here, one fellow mentioned removing the timing device by prying the chain off the timing device with screwdrivers. I am considering this option to avoid removing the injection pump. What I wish to do is remove tension from the chain (remove tensioner bolt), and if necessary, remove the camshaft sprocket, so that the chain can easily be removed from the timing device. From there, it seems replacing the intermediate shaft bushing would be straightforward.

What says the council? I realize removing the injection pump is the recommended procedure, but if one fellow removed the timing device from the front, so can I. However, he never posted the results of his work, so maybe he did NOT get the timing device reinstalled.

Jurgen

Stretch · #15 08-29-2013, 02:06 PM

Quote:

Originally Posted by turbo6bar

It has been a while since I last posted here. I replaced the vacuum pump, and upon starting the car noticed it had a pronounced ticking from the vacuum pump area. Before replacing the pump, I measured the end play of the intermediate shaft and the reading was twice the maximum specification. I believe this excessive end play resulted in failure of the original vacuum pump and left unchecked, will destroy the replacement.

Reading an old thread here, one fellow mentioned removing the timing device by prying the chain off the timing device with screwdrivers. I am considering this option to avoid removing the injection pump. What I wish to do is remove tension from the chain (remove tensioner bolt), and if necessary, remove the camshaft sprocket, so that the chain can easily be removed from the timing device. From there, it seems replacing the intermediate shaft bushing would be straightforward.

What says the council? I realize removing the injection pump is the recommended procedure, but if one fellow removed the timing device from the front, so can I. However, he never posted the results of his work, so maybe he did NOT get the timing device reinstalled.

Jurgen

If you don't want to remove the IP because you don't want to do a drip test you are probably going to be disappointed - if you take out the timing device the way you said the IP will most likely spin...

...you might get away with locking the governor by removing a plug and fitting a wheel bolt though (I can show this in a picture if need be)...

...and then you need to lock both the crank and the cam...

...but - well - I don't fancy your chances.