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73 450SL
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Discussion Starter · #1 ·
Does anyone have the vacuum diagram for a 73 450SL that they would be willing to share?

I think I've developed a vac leak after doing some detailing under the hood. Idle has become rough right after I was finished.

Thanks
 

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Always Remembered RIP
1973 450 SLC AMG, 1995 Chevy Tahoe
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The pic is bad but thats it i think on the top of the page
 

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Discussion Starter · #3 ·
Thanks ussun. I'll try to make it big enough for my old eyes. What manual is this from?
 

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Always Remembered RIP
1973 450 SLC AMG, 1995 Chevy Tahoe
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Haynes 63030 (698)
but it the wrong one sorry I just check
 

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'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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Haynes 63030 (698)
but it the wrong one sorry I just check
There are diagrams in the manual section 80-900/1/2 . I only have paper version, but maybe these are on-line somewhere?
 

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73 450SL
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Discussion Starter · #7 ·
Thanks again everyone, however my search continues. I checked my Haynes manual, but it only goes back to 74 with pics of the vacuum system.

Any other ideas?
 

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1975, 280SL
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What you are looking for is the MBz heating and A/C manual available from them or TMC publications. According to mine, 73-77 107's are all system 1
with version 1 going up to chassis #021 956 and version 2 after that.
 

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1980 450SL & 1988 560SL
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2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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I don't think that's right. He's asking about a 73 which would have the D Jetronic engine. That diagram has something that looks suspiciously like a WUR - D-Jet didn't come with a WUR. That diagram looks like it belongs to a federal K-Jet system (as opposed to a California K-Jet).
 

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1980 450SL & 1988 560SL
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Yea, it is. I got it from the 73 section. i just didn;t look at it first. Crappy manual. I'm still looking for the correct one.
 

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1980 450SL & 1988 560SL
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73  dist.jpg

This is all I can find except for the A/C and door locks system.
 

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'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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Doesn't anyone own the shop manuals on CD or paper?

I don't know if this is what you need, but my manual as these three diagrams. Maybe one will match your car?



 

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2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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Doesn't anyone own the shop manuals on CD or paper?
Yes, both. And I was going to say this earlier, but decided it might come across as me being a smartass - the AC manual doesn't cover the engine, it only covers the AC. I also have that one in printed form. He needs a vacuum diagram specific to his pre-smog D-Jet engine - not even the one I have for my California smog edition 75 with D-Jet would work, because there are significant changes between the years.

I don't know if this is what you need, but my manual as these three diagrams. Maybe one will match your car?
None of them cover the engine, unfortunately, and that's what he's wanting.
 

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'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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Yes, both. And I was going to say this earlier, but decided it might come across as me being a smartass - the AC manual doesn't cover the engine, it only covers the AC. I also have that one in printed form. He needs a vacuum diagram specific to his pre-smog D-Jet engine - not even the one I have for my California smog edition 75 with D-Jet would work, because there are significant changes between the years.

None of them cover the engine, unfortunately, and that's what he's wanting.
The only vacuum connection diagram for the engine, is so simple, it is hardly worthwhile posting. It IS in the manual many times over! It is just a tube that connects to the throttle housing at one end and the distributor vac advance at the other end, with a switchover valve part way along. If the tubes are off it can affect the engine somewhat, because it creates a vacuum leak.

Other than that, there is the vacuum line to the brake unit - unlikely to have knocked that off!

That leaves the door locking system that I posted - A '73 probably has the second system - 901. The diagram shows the connection that comes off the back of the inlet manifold and goes to the door locking system via a check valve. That could be where the problem is - most likely disturbed the line leading to the check valve.

I don't think there are any other vacuum connections that detailing could have disturbed. (I doubt he could have disturbed the lines between the throttle and the AAV/Idle valve.)
 

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73 450SL
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Discussion Starter · #16 ·
Thanks for the extra effort you guys have put forth. I'm sure I'll have a use for the entire car vac system diagram.

Could it really be as simple as what Nascar posted??? I can only hope. After all it is a pre-smog engine, so maybe.

I'm going out to look soon and I'll report back.

Thanks again for the outstanding collection of information.
 

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Could it really be as simple as what Nascar posted??? I can only hope. After all it is a pre-smog engine, so maybe.
No - that diagram is not same as on early cars. This is all there is to it if you have just one connection on your distributor. (But don't forget to check the connection at the back of the engine leading to the door lock system via a check valve.)
 

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Discussion Starter · #18 · (Edited)
OK guys. Yes, the car is as simple as the diagrams. One from the distributor to switchover valve to the throttle body. Just like w107 posted.

Now, this is what I found disconnected.



What is that?

and while was looking I discovered this. What do you guys make of this? The switch (for the lack of a better term) on the right has nothing connected to it like the one on the left and there is a red line that is plugged.



and



Thanks for your help with diagrams. Now any thoughts on this?
 

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Now, this is what I found disconnected.
What is that?
That's the manifold vacuum sensor. Plugging it back in is a good thing.

The rest of it is all vacuum connections, and why your system isn't actually as simple as the diagram showed. You need a complete vacuum diagram.
 

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That is so simple, it's beautiful in the engineering.
I don't see a reference I am familiar with, anybody got a vacuum for the simple system.
 
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