Getting ready to replace the vacuum pump on my '602 tomorrow, and I have a few questions (believe me, I looked through my FSM, can't find the procedure anywhere).

- Does the engine need to be in any specific position during removal? I understand you need to align the rollers so that you don't damage the new one during installation, but can you remove the old pump in basically any crank position?

- The Pierburg instructions say something about removing a "timing basket" when you remove the old pump, but not replacing it when the new pump goes in. Why would I not replace something I just removed from my engine when I put it back together?

- Torque values for the VP fasteners?

- Any other tips?

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Just undo the bolts evenly. If the pump isn't in an ideal location, there will probably be some tension on the fasteners, just keep it undoing them evenly and press in to relieve tension as you go.

The gasket that probably came with the pump has a "dam" at the bottom, I expect to retain some oil. The assembly basket which is left in place at the factory will interfere with it. Take out the additional bolts that hold the basket, and keep this stuff somewhere safe.

Before you install the new pump, blip the engine so the roller cam is positioned 'low', that way there won't be tenstion on the bolts as you go in.

Clean the hex bolt's openings HOSPITAL CLEAN before attempting to loosen any or be ready to cry.....

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

No the engine doens't have to be in any specific order, but if it makes you feel better put it at TDC. It takes 2 seconds of time.

The torque spec is "snug". They don't need to be ridiculously tight. When I remove the vacuum pump, I take off the metal housing. Be careful with those allen bolts.. They're probably stripped from a previous mechanic.

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Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k

Engine at TDC puts minimal pressure on the pump spring. Early engines require the dam gasket. There are optional outline gaskets in metal or fiber which fit around the basket.

Check the tensioner arm and pulley while you're in there.

Sixto
83 300SD can be yours
98 E320 wagon

The basket is only there to aid in the removal of the injection pump timer; it helps to hold the timing chain in place. It is not required at any other time. Don't toss it! If you ever need one in the future, the price for that simple piece of stamped steel is rather steep.

Once you have the new pump in place, I used 25 Nm as the tightening torque for the screws, but less is probably sufficient. It just needs to be tight enough that it doesn't leak oil and the screws won't back out from engine vibration.

Important break-in procedure: put some clean engine oil into the big vacuum line connection at the top before connecting that line. I think 10 cc? Not a whole lot, but enough to "prime the pump".

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

Thanks everyone for the responses - I appreciate it.

Do I need to pull the valve cover to get at the cam sprocket marks? Or do I just set the crank to a certain number (01)?

Thanks, tensioner arm and pulley replacement are what got me here - I figured I'd use the opportunity and excellent access to change the VP. Plus, I think the gasket is leaking.

Noted - will not lose the timing basket! I noticed the new gasket looked kind of funky (with the dam).

Do you add the oil with the engine running, like the Pierburg instructions state? It seems like enough of a PITA to get a little bit of oil in that little hole with a dead engine, much less one that is jumping around allover the place...

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Turn the crank until the indicator at the 11 o'clock position is over the 0|T mark.

Sixto
83 300SD can be yours
98 E320 wagon

I believe I added the oil to the running engine. Now that I think about it, I used the smaller of the two vacuum lines, stuck the opposite end into a container with the oil and let it suck the oil into the pump.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

And then look through the oil fill hole in the valve cover to make sure both lobes for #1 cylinder are up.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

No risk of hydrolocking the pump?

Sixto
83 300SD can be yours
98 E320 wagon

Dr. Marshall Booth (RIP) recommended this procedure to treat noisy vacuum pumps on OM61x engines. Pierburg includes this in their pump installation instructions.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

Well, the VP came off without too much trouble. Started out using a 10mm box-end wrench for the tough-to-reach fasteners until I had the bright idea to use a socket on an extension. Duh. Anyway, no drama.

Gasket was pretty hosed, and I think it's safe to attribute at least some of my oil leakage to this. We'll see if the front end of the block stays dry after I put everything back together and run the motor a little while.

One issue I'm having, though, has to do with the Pierburg instructions. First of all, they say to remove the timing basket - I don't know what that is exactly, or what it looks like, but I don't see anything removable, other than the big left-handed bolt that holds the IP in place. The VP is stamped with a 1997 manufacture date, and is the newer type (although the gasket is the older type?) so obviously the pump is not original - maybe the timing basket was removed and discarded?

The second thing is that the instructions mention to NOT install a new VP if there are ANY signs of wear on the stroke curve. I don't see how a 25-year-old engine is supposed to not have any wear on such a part, but whatever. In the (admittedly poor) picture below, you can see a shiny spot on the upper right of the stroke curve - a similar mark is on the lower left. The picture I think looks worse than t actually is - in real life, it doesn't look scored at all, just shiny. I mean, technically, I suppose this is wear. But I'll be damned if I'm going to replace the entire timing device, as suggested by the instructions!

Thoughts? I mean, I guess it doesn't matter - I'm putting it back together with the new pump as is, just wondering if I can expect catastrophe to ensue, lol.

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The basket is held by 3 bolts that take a 13mm wrench just inside the gasket outline. There's no basket in your picture. It was removed and discarded when they installed the previous pump. Did it have a dam gasket?

I suppose shiny spots are okay. If a previous pump failure severely damaged the drive cam, the new pump won't last long. Seems the pump you just removed is in good shape. Check the roller closely to confirm. If so, the new pump should be fine driven by the drive cam with shiny spots.

Sixto
83 300SD can be yours
98 E320 wagon

No dam gasket, which I found surprising, given the newer design of the pump. The take-off also had the Star ground off, so I know it wasn't an original or Genuine replacement part.

I will reinspect the roller of the pump (and the rest of it), but my initial impression was that it looked fine, other than the degradation of the gasket.

Thanks everyone for all the feedback.

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