I was bored and fooling around with a spare transmission vacuum control valve which had previously held vacuum(with a very very slight leakage) at 18" and diminished with the lever to around 4" at the stop, when I broke the thing I think. Now it only pumps to 16" and leaks down slightly quicker. The lever arm does take it down to zero though which is what I understand is normal operation. Is it supposed to hold vacuum indefinitely, and what is the max vacuum it should hold? I may have ruined a perfectly good valve but at least I know how it works now. Maybe.

__________________
'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

Humbleness is the beginning of healing... Live and learn eh?

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83 300sd, 280K Blue/Blue Leather (~24mpg)
95 E300D, 150K Champaigne/Parchment(~33mpg)

Is probably okay as the vacuum pump will overcome minor leaks due to the volume of air it can move.

You are correct though that it should go to zero at the stop and in reality should probably hold vacuum forever if brand new...

The test would be to put it on the car (or just attach it) and test it with your cars vacuum supply. Use a tee like the current setup to the tranny and you can read it's bleed characteristics on the tranny side as it is moved from closed (resting, full vacuum) to fully open at the stop (no vacuum).

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'99 S420 - Mommies
'72 280SE 4.5 - looking to breathe life into it
'84 300SD Grey - Sold
'85 300SD Silver - Sold
'78 Ski Nautique

Seeing the title of this thread, I wondered "Is this Will Smith's next movie?"

Yeah, don't feel bad, we've all been there. I remember snapping that dinky little tube that runs between the water pump and the block of my 617. Fortunately I was changing the pump at my friend's house and he had a spare. D'oh!

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1982 300SD

just did that myself. idiots anonymous?

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1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

.............run the rear brake reservoir out of fluid and think the master cylinder has failed...............

Are you making fun of me?

Is that a challenge?! you're on!

__________________


1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

...................nah, making fun of myself......................

Can I blame it on the German design of the reservoir (they purposely tried to trick me).

how about tracing a vacuum leak with a leaking vacuum tester and thinking all the actuators were leaking. been there done that.

__________________


1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

Did I ruin a $180 part? The valve will hold approx. 17" of vacuum maximum, and begin to slowly leak down immediately, in a linear fashion. Total time it takes to leak to 12" is 40 minutes. Are these things supposed to hold vacuum forever?

__________________
'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

You are talking about the vacuum modulator no?

I had a spare from my old 123, and when I thought my 124 was leaking, I replaced it with the spare. I took the replaced one and disected it and found the diaphragm material they use to be quite durable and in good condition. I didn't have a MityVac at that time to test it, but it did not appear to leak. The spare I put in seemed to correct my hard shifts, so there must have been something leaking with the old one, maybe the plastic body, or bad sealing of the diaphragm.

I broke the plastic rod that the modulator pushes inside the tranny! Very brittle and warn anyone to be real careful of that!

How about looking for a water leak in the cabin and spending an afternoon in search of only to find that someone [we won't mention names here but we're married if thats any clue] spilled water from a cup and didn't tell anybody?

How about wringing off a bolt only to find it's left hand threads? Worst thing is I've done that more than once. Uh, not the same bolt....

Anybody need their car worked on?

Cheers,
Bill

that reminds me...
once took apart almost a whole dash on an ML trying to trace the source of a water leak. damn a-pillar trim is plastic on the inside...water was running down it from the sunroof and dripping out from behind the dash...oh well, I learned what to look for next time...

__________________


1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

I once fixed a " f&^*#!! " plugged galley sink...

by removing the stopper...

in front of the first furious then humble owner of a 2 million dollar yacht

(not that I haven't done some dumbass moves, but this it one of my all-time favorites)