602 Vacuum Pump Basic Questions - PeachParts Mercedes-Benz Forum

shertex · #1 06-01-2011, 08:31 AM

I've been reading various vacuum pump horror stories, particularly related to the 603. My questions, though, are related to the 602.

1. When have folks seen original 602 vacuum pumps fail?

2. When they fail, what's the extent of the potential damage to other components? Is a 602 at risk for catastrophic damage?

3. In particular, is the design such that, if it fails, bearings won't be thrown into the timing chain?

My 1992 300D is coming up on 228,000 miles....just wondering if I should be concerned.

Thanks!

vstech · #2 06-01-2011, 09:37 AM

602 has the same VP issues as any 60x motor.

Oldwolf · #3 06-01-2011, 10:40 AM

The VP in my 602 failed at about 150K. It was the original unit. The failure was not catastrophic, it just started having problems keeping the vacuum up high enough for the power brakes to work reliably. I have pictures somewhere if you want to see them.

shertex · #4 06-01-2011, 10:44 AM

Quote:

Originally Posted by Oldwolf

The VP in my 602 failed at about 150K. It was the original unit. The failure was not catastrophic, it just started having problems keeping the vacuum up high enough for the power brakes to work reliably. I have pictures somewhere if you want to see them.

Nice you got some warning. It's such an expensive repair I'm very reluctant to do it based purely on mileage....but I'd be glad to do it at the first sign of vacuum problems.

Oldwolf · #5 06-01-2011, 10:52 AM

My 602 had the older VP design, the one that could drop the ball bearing into the engine. Not sure if the newer ones did though. Yours probably is like mine with the open cage design.

compress ignite · #6 06-01-2011, 07:06 PM

At that Mileage

I'd order a New Metallic gasket (One time use only) and R+R the V.P. to
inspect IT AND THE "RAMPS".

Some of the "Failures" have Not involved the Bearings BUT could have been
just as Catastrophic to the engine

Maxbumpo · #7 06-02-2011, 08:43 AM

Quote:

Originally Posted by shertex

Nice you got some warning. It's such an expensive repair I'm very reluctant to do it based purely on mileage....but I'd be glad to do it at the first sign of vacuum problems.

I would not bet my engine on getting a warning. If your car has more than 125k miles (earliest mileage at which original pumps start failing) than I'd highly recommend doing the job if your pump has the crimped on cover. The pump may fail with no warning at all, and then you will need an engine replacement!

selkin76 · #8 06-02-2011, 09:19 AM

I was just thinking about this the other day. Do you know where I can find a repair guide that shows how to go about replacing the VP? I was thinking about getting the FSM for this model. Would it be covered in that?

scottmcphee · #9 06-02-2011, 09:26 AM

Vac pump repair is in a similar category as "when should I replace the timing chain".

When you *need* to, it's too late and up until that moment, you're fine.

Maxbumpo · #10 06-02-2011, 12:26 PM

Quote:

Originally Posted by selkin76

I was thinking about getting the FSM for this model. Would it be covered in that?

Yes, but it's really not that tough. If you're an experienced DIY'er, the directions that come in the box with the new pump are sufficient.

compress ignite · #11 06-02-2011, 02:49 PM

Max,

I've got a Brand New #000 230 31 65, still in it's box.
'No Instructions provided(?)
('Somebody snitched mine?)

Any chance yours detail the Torque Specs for the six bolts securing the Pump
to the Timing Cover?

Thanks.

scottmcphee · #12 06-02-2011, 05:34 PM

Don't go crazy on those bolts.
They're fine threaded and screwed into aluminum. \
"Wrist tight but not white knuckle tight"

Maxbumpo · #13 06-03-2011, 08:21 AM

Quote:

Originally Posted by compress ignite

Max,

I've got a Brand New #000 230 31 65, still in it's box.
'No Instructions provided(?)
('Somebody snitched mine?)

Any chance yours detail the Torque Specs for the six bolts securing the Pump
to the Timing Cover?

Thanks.

I think I was wrong about the instructions coming in the box, as I recall Marshall Booth provided this copy from the Pierburg folks, and no copy was with either of the two pumps I've installed.

Attached is copy of the Pierburg pump installation instructions, but no torque spec provided. I've looked in the FSM, procedure 43-0618 (only found in 126 FSM) and 07.1-8014, but again no spec. Looked in the Technical Data Manual; no spec.

What to do? Common sense applies: tighten until it doesn't leak but don't break off any bolts. I think that if you start with 15Nm and then check for leaks you'll be fine.