Hi, So I have my car finally delivered but, my trunk lock wont turn and vacuum doesnt work.

Does the key work in the glovebox? It's possible you have a Valet key which will operate the door and ignition, but not glovebox and trunk.

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Hi, Thanks for the reply.

I only have two keys with me one for the doors one for the ignition. (both squared head)

My glovebox doesnt have the keyhole.

When my W123 300D was left not driven at all for many years, it became very difficult to open the trunk. But since refurbishing the car and now driving it two or three times a week, the vacuum trunk lock system works normally again, and the trunk opens as it should.
Maybe if you are able to drive the car that will restore the vacuum trunk mechanism, I just don't know how long a drive it would take, though.

? How to do you put pressure on the vacuum lock and open it?

I have a vacuum problem in this car. The engine will only shut off when drivers door is locked.

If it is a W123 as I suggested in the other post you could apply another vacuum source to the Door Lock Circuit like a Air Conditioning Vacuum pump or you could pull a Vehicle with a Gasoline Engine next to your Mercedes and run a vacuum line from an intake manifold source of vacuum. That would be the Vacuum Supply.

Also the Vacuum Lines are Color Coded. You can access the Vacuum lines by removing the Plastic Piece at below the Door that holds the Carpet down and peel back the Carpet and that exposes the Vacuum lines and their rubber connections.

If you get the color codes of the Vacuum Tubings from another thread you can isolate the one going back to the Trunk.

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84 300D, 82 Volvo 244Gl Diesel

Would this be considered jump starting a diesel or giving it a transfusion?

If you have an old style mechanical fuel pump, these make a great vacuum / low pressure pump. Just bolt a handle to the mount / weld on a handle to the lever.

Unfortunately on a W123 there is a rather large vacuum reservoir. Assuming there was no vacuum leaks that would take a while to evacuate with anything manually powered.

You also need something that if there is a leak in the system will evacuate the system fast enough to still have enough vacuum to operate the trunk lock. Also why it is better to tap into directly into the Trunk Lock Vacuum Line.

See the diagram. Both the Diesel and the Gassers have the #6 Vacuum Resirvoir for the locking system.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Well my engine shut off works now. Check valve broke.

Now the rest of the system. Another check valve behind the cluster.

THANK YOU for this diagram ! .

If you remove the passenger front footwell carpet and gently unlatch and raise up the black plastic cover you'll see #22 is TWO three way vacuum rubber connectors ~ this is the ideal place to connect the vacuum source to unlock the trunk .

FWIW, the large vacuum resivoir has a completely separate solid yellow pipe leading directly to it from under the hood on the firewall ~ it doesn't take a long time with a manual 'Mity-Vac' tool to begin filling it, you'll notice the vacuum gauge beginning to rise off the peg slightly after 6 ~ 9 pumps .

This is do - ale @ home much more easily and cheaper than you think so don't give up yet .

Please post a photograph of the trunk's lock cylinder A.S.A.P., there's important info there .

I was recently told that all W123 Coupes have the emergency release wire but they don't, I have looked *very* closely having owned four CD's .

-Nate

I just did a web search using the following query:
how to find leak in the vacuum door and trunk locks of W123 mercedes

There are a few of the first sites listed from the search, you can do the same search and scroll further down the search results to see if anything looks promising. I haven't looked at any of them, so am just posting them for you in case any of them may be of help in your situation. If these aren't what you need, you might try doing a different web search with a query that better matches your car's problem. Wish I could be of more help!:

The Basics of Tracking Down Vacuum Leaks
The Basics of Tracking Down Vacuum Leaks


Mercedes 123 Vacuum Door Lock Diagnosis Tip by Kent Bergsma
https://www.youtube.com/watch?v=HoVVUMvEPx8


Mercedes-Benz W123 Vacuum Door Lock System
This video gives a brief description of the overall vacuum system and shows component locations, actual parts, and system diagnostics for the W123 door locks.
https://www.youtube.com/watch?v=Axn3HD_wjL8


Repairing Mercedes W123 Door Lock Master Vacuum Switch
https://www.ifixit.com/Guide/Repairing+Mercedes+W123+Door+Lock+Master+Vacuum+Switch/20887


How to Test a W123 Vacuum Door Lock Actuator
https://**************.com/problems/vacuum/how-test-a-w123-vacuum-door-lock-actuator

The following site has good pictures of the course that the vacuum tubes take in the W123:

Mercedes W123 Vacuum Lock System Diagnosis Technique
https://www.ifixit.com/Guide/Mercedes+W123+Vacuum+Lock+System+Diagnosis+Technique/20201

How to open from the back side:

https://www.peachparts.com/Wikka/W123TrunkBreakIn

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have an accident

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www.kiva.org It's not like there's anything wrong with feeling good, is there?

I would try an other source of vacuum first. In those vacuum threads locate where the locking system check valve is under the hood. Mine has one nipple on the vacuum supply side and 2 nipples with 2 lines connected going to the locking system. Connect your vacuum source to the single vacuum supply side nipple.

If you can't restore the stock vacuum:
Due to the vacuum reservoir on the locking system I think it would take a lot of pumping whith a hand held vacuum tester to supply the vacuum.
Ideal would be one of those vacuum pump pumps people use when they recharge their air confiding system.
If you have a gasoline car you could pull up to the Mercedes and connect the gasser manifold vacuum with a long vacuum hose to the Mercedes.

I don't know if the Dealers are still cutting new Keys using the vin or not. If they are you could get a new key made and hope the Trunk Lock matches it.

I opted to buy a used Trunk Lock with a key on eBay it also came with Door Locks and Ignition Lock Tumbler. I disconnected the vacuum from the locking system and just do it manually and I like it better that way. No more need to worry about vacuum lock system failures.

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84 300D, 82 Volvo 244Gl Diesel

Ah I forgot it to do this......... Thank you.