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If not my first post it is certainly only my second or third. There is a lot of great information on here. I look forward to absorbing as much as possible. I recently purchased a 300DT in what I think is great condition. White with black interior. Was a great body until I threw a tire tread that damaged the front passenger fender along with ripping out the turn signal and wiring, but that's another story.

I have a vacuum question. Please take a look at the image and let me know what you think. It doesn't look right to me. None of the door locks work and some are hard to unlock, then they re-lock on their own. After reading tonight, it appears the change over valve has been bypassed. I'll correct that. My main concern is the loop back through the firewall at the check valve.
 

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1978 W123 300D, 1986 S124 250TD, 1987 W124 300D-T, 1965 W108 250SE, 114 280C, W126 300SDL,W123 300CD
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that shouldn't be a loop. ill try to check my diagrams. will post it later if i have it
 

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2013 MINI Copper S Clubman, '84 300CD-weekend car
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The yellow check valve should have a vacuum source plugged into it, not the green (HVAC) line, it needs a vacuum source also.

If you would, pull back a bit to show the nipples on the main vac line and where they go.
 

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1978 W123 300D, 1986 S124 250TD, 1987 W124 300D-T, 1965 W108 250SE, 114 280C, W126 300SDL,W123 300CD
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83 Posts
here it is but i don't know which is yours. pardon me im from a different country and i get confused with california and federal.
 

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Discussion Starter #7
The yellow check valve should have a vacuum source plugged into it, not the green (HVAC) line, it needs a vacuum source also.

If you would, pull back a bit to show the nipples on the main vac line and where they go.
Here's the pulled back picture. Everyone's help is greatly appreciated!
 

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2013 MINI Copper S Clubman, '84 300CD-weekend car
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Okay, you have the version on the left in post #6. That shows the egr set up, it can be bypassed.

The nipple going to the brown line needs one of these: Your Parts Search Returned 3 Part(s) the second one. Which should have the yellow check valve, the green line and the brown line coming off it.
 
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