Anyone know what this noise is? 1987 300td wagon - PeachParts Mercedes-Benz Forum

Tdwagonin' · #1 08-20-2017, 10:06 PM

Hello,

I just started hearing a new noise coming from my 1987 300td wagon. Does anyone know what it might be? In the video, it is that puking sound(not sure how to describe it).

Thanks for the help

https://youtu.be/ktXrtLuk3CA

Diseasel300 · #2 08-20-2017, 10:25 PM

Vacuum pump. Shut it down, pull it and check it! If it's toast or the face cam is eaten up, don't drive the car until it's replaced!

sixto · #3 08-21-2017, 12:30 AM

x2 I wouldn't start it again before checking the vacuum pump.

Sixto
98 E320s sedan and wagon

Mxfrank · #4 08-21-2017, 07:20 AM

Likely the vacuum pump, but to be sure take the serp belt off. That eliminates a lot of potential sources. You can safely run for a minute or two without the water pump.

Tdwagonin' · #5 08-21-2017, 12:46 PM

The vacuum pump is definitely not in good shape. I just noticed it is leaking oil out of the bottom part. The outside cover is moving as well. I just bought a new one and will try to replace it. Are there any detailed instructions on how to replace this?

Thanks

Mxfrank · #6 08-21-2017, 03:37 PM

Take the bolts out evenly, a little at a time. That way, if it's "on the cam", it will come out without risking a broken bolt. Afterwards, flip the key to advance the cam so that the new pump fits without fuss. If you bought a Pierburg replacement, it will come with a "dam" gasket. In this case, you will need to remove the timing basket in order to install the gasket (or cheat and file away enough of the gasket to clear the bolt). If you remove the timing basket, store it and it's bolts somewhere safe...you may need to r&r the injection pump someday. Then just bolt the new pump in place. The pump will come with instructions for priming with a bit of fresh oil.

Tdwagonin' · #7 08-22-2017, 06:25 PM

Thank you Mxfrank. What do you mean flip the key to advance the cam?

What do I need to remove before I can get at the vacuum pump? I don't want to take too much off if I don't need to.

I purchased this one

Mercedes W124 W126 W140 W201 W210 300D Diesel Vacuum Pump 1995-2006 BG13003 | eBay

sixto · #8 08-22-2017, 06:35 PM

Set the crank to TDC for minimal pressure on the pump drive mechanism.

The shroud, clutch fan, power steering pulley and belt tensioner pulley have to come off. IIRC the tensioner itself can be positioned out of the way with the spring and damper disconnected up top. Consider buying a later 2-piece fan shroud for better access to the fan bolt if you have a single piece shroud.

Sixto
98 E320s sedan and wagon

Mxfrank · #9 08-22-2017, 09:26 PM

Quote:

Originally Posted by Tdwagonin'

Thank you Mxfrank. What do you mean flip the key to advance the cam?

There's a cam on the front of your injection pump that works the vacuum "pump handle" up and down. If you happen to stop the engine with the cam at full lift, there will be tension on the vacuum pump. You can blip the starter to move the pump "off cam," which will make installation and removal a bit easier. You'll understand what I'm talking about when you have the vacuum pump out.

Tdwagonin' · #10 09-11-2017, 08:12 PM

Update!

It was definitely the Vacuum pump. I just changed it and now everything sounds great.

To change it I had to remove the rad and loosen the belt then I had enough space to remove and replace the vacuum pump.

Thank you all for the help.

Junkman · #11 09-11-2017, 09:54 PM

Keep the old one for parts. 617 rebuild kits are NLA. Yours is not far behind. You may be able to find bearings at a bearing supply. Check valves only come from another Mercedes pump.

Diseasel300 · #12 09-11-2017, 10:28 PM

The 60x series vac pumps are not worth rebuilding. The early models which are now wearing out have design flaws that will not be corrected by a rebuild. They run risk of catastrophic damage to the engine if one of the bearings lets go. The newer style has a redesigned cam follower that significantly reduces the risk of damage to the engine in the event of a vac pump failure.

Rebuilding a piston style pump is penny wise and pound foolish anyway. You're on borrowed time by the point it's worn to the point of failure. A rebuild kit (if you can even find one) is half the cost of a new pump. Why bother.

sixto · #13 09-11-2017, 10:37 PM

Quote:

Originally Posted by Diseasel300

A rebuild kit (if you can even find one) is half the cost of a new pump. Why bother.

I think the point is that replacement pumps could become NLA.

Quote:

Originally Posted by Tdwagonin'

It was definitely the Vacuum pump. I just changed it and now everything sounds great.

Do you have pictures of the old pump? I'm curious to see if both bearings still have 6 balls and plastic separators. Otherwise, what was making noise? Was the pump drive on the IP sprocket scored?

Sixto
98 E320s sedan and wagon

Tdwagonin' · #14 09-20-2017, 04:01 PM

Quote:

Originally Posted by sixto

I think the point is that replacement pumps could become NLA.

Do you have pictures of the old pump? I'm curious to see if both bearings still have 6 balls and plastic separators. Otherwise, what was making noise? Was the pump drive on the IP sprocket scored?

Sixto
98 E320s sedan and wagon

I will get a pic and post it. What do you mean the IP sprocket?

jay_bob · #15 09-20-2017, 06:45 PM

The gear on the IP shaft (driven by the timing chain) has a roller-coaster like track on it. The pump cam rides on this track to produce the pumping action. If the cam bearings fail then the roller digs grooves into this track.

This is the piece you see inside the engine with the vacuum pump off.