On my '79 300D, a part I found to be kind of obscure failed and started hemorrhaging radiator fluid. It is the Vacuum valve or faucet as referred to by the parts guy. There were two in the US so they shipped one to Seattle from New Jersey. Got the part, went to put it in and found that, tho they looked nearly identical, the old valve's input/output ports were approx 1/2" while the new part's input/output as significantly smaller at about 1/4". see attached photos

After doing a bunch of research at the parts counter, they couldn't find any record of why the difference or if this was a problem....otherthan the fact that I'm struggling to get proper reducers to install this thing.

Anyone have experience with this?

Thanks -harv

Attached Thumbnails

   

Oh, the part number is A 000 830 14 84 and is a Mercedes original product

It's part of the unwired tools ACCII electronic upgrade kit.

__________________
Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

Do not use reducers, it will not function correctly. The valve you have there is your defrost bypass valve. When the system is set to defrost it bypasses the Climate control servo and routes full unrestricted water flow to the heater core. Its a safety device really as it allows you to have heat if the servo fails so you can see through the windshield, as well as stay warm.

The little valve you have there will not allow for anywhere near enough flow through the heater core. These are not a high failure item and you'd probably have pretty good success getting one from a junk yard.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

They use one with there kit as well, however the part he has there is stock on the ACII systems.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

Yes I believe that on this ACC system that is a vacuum valve for full flow heat on Defrost. It's why you can normally still get heat on these cars in Defrost even when the servo is stuck closed. Sort of a fail safe, as a result, for that safety related aspect of the system.

__________________
1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

The Baja Arizona Oil Burners Send a message if you'd like to join the fun
Left to Right - UberWasser, Iridium, Stuttgart-->Seattle,, mannys9130

Visit the W123 page on iFixit for over 70 helpful DIY guides!

This is not a stock component for ACCII

__________________
Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

Yes it is, If I can find an engine shot of my 1979 300D I can show you.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

the w201 (190e and 190d) use a part identical in function but sized slightly different.

I have one around if you need a measurement. But its easy to find and order a new one. It replaces the monovalve in the w123 I believe.

__________________

His system is pre-monovalve

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

Interesting mystery to get to the bottom of. May have been some servo bypass modification done to yours.

__________________
Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

Except here it is on my '79 300D, stock.



It's part #188 in this diagram:

__________________
1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

The Baja Arizona Oil Burners Send a message if you'd like to join the fun
Left to Right - UberWasser, Iridium, Stuttgart-->Seattle,, mannys9130

Visit the W123 page on iFixit for over 70 helpful DIY guides!

Nope. Stock. See above.

__________________
1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

The Baja Arizona Oil Burners Send a message if you'd like to join the fun
Left to Right - UberWasser, Iridium, Stuttgart-->Seattle,, mannys9130

Visit the W123 page on iFixit for over 70 helpful DIY guides!

Thanks Uberwasser, I could not for the life of me find the pic of my engine bay. I knew I wasn't going crazy.

@phillytwotank: As I stated above its a failsafe valve for defrost. 100% stock on these systems

To reiterate for the original poster, you should return the valve you were sold. It is the wrong one and will not work correctly.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

Correct.

I am just helping to describe it.

The w201 valve is not a mixing valve. It opens or closes by vacuum.

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