Thanks all but, my lock won't budge it has been soaked in JB80 for days now. No way to access the unlock through license plate lights?

"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."

FYI: I just had a couple keys made for my '85 300TD by VIN #. Mercedes requires the dealer to have a copy of your title and your drivers license. I was able to fax both to the dealer. Took a couple days and $23.00 each to get. They work great.
This may not be for long for the older models, though. The dealer said they are no longer able to get blanks for some models and years. I don't know if this is a temporary or permanent problem. (Sounded like for mostly
late 80's and early 90's.)

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85 300TD

88 560SL

05 SL65 AMG

Good morning Rocky ;

I well understand the not using oil as it does indeed both attract dust and also gums up locks as it dries up .

However you also said not to use graphite, it's what our typ of locks were designed for being a dry lubricant .

The liquid graphite I use is in an aerosol can and the liquid evaporates quickly, leaving behind only dry graphite after the liquid carrying agent wicks the graphite into every nook and cranny ~ I've been using it for close to 40 years now and on the original key locks in my 1923 house, no problems ever .

Give it a try .

I often take old key locks apart for cleaning and key matching, it's tedious but not terribly hard on many older automotive locks .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Have you contacted the previous owner to see if there is another key? The lock may have been changed as some point so getting one from the VIN might not work, however, it may get you duplicate for other locks.

Gently wiggling the key tends to work better than forcing. With worn keys I've gently pulled the key in and out in an attempt to " Pick " the lock.

You could try to " rake the pins " with a piece of very stiff wire. ( like straight wire from a spring. ), this might dislodge the upper pins.

To go farther if this is a standard single sided pin type lock, try to pick the lock with the wire and a small screwdriver. With the small screwdriver in the slot providing very light tension in the desired direction of rotation, repeatedly rake the pins and the lock may turn.

I've done this on various locks, it works better on worn locks.

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

I have never scene pics of the security system on a W123. But if your w123 has the security alarm system below the Rear Seat on the Drivers Side there is a pull cable to open 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

See the parts diagram. The Pull Cable is attached to the alarm/antitheft part #661. If you don't have the alarm/antitheft system you won't have the pull cable.

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84 300D, 82 Volvo 244Gl Diesel

I have only seen these in W126's, and never in a W123. I am not saying they don't exist, I just have never seen one in any W123 (and I have seen MANY).

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All Diesel Fleet
1985 R107 300SLD TURBODIESEL
2005 E320 CDI (daily)

LOTS of parts for sale!


EGR block kit
http://www.peachparts.com/shopforum/diesel-discussion/355250-sale-egr-delete-block-off-plate-kit.html

1985 CA emissions 617 owners- You Need This!
Sanden style A/C Compressor Mounting Kit for your 616/ 617 For Sale + Install Inst.

Sanden Instalation Guide (post 11):
http://www.peachparts.com/shopforum/diesel-discussion/367883-sanden-retrofit-installation-guide.html

There is the Mercedes that I own I bought stuff like the service manual and the rest of the knowlege comes from what I read on these forums and is why I continue to increase my knowledge from this forum.

I have another diagram of a W116 with the same unit.

I mentioned the pull cable because it would be awful to go through the work to open the trunk when there is a small chance that all he had to do was pull a cable.

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84 300D, 82 Volvo 244Gl Diesel

Picture of the lock.

There you go ~ your trunk is in the passive locked mode and applying vacuum to the yellow pipe with green stripe at the T connection under the carpet in the right foot well should unlock it .

The T connector will have pipes leaning backwards, those are the ones going to the trunk and fuel filler flap .

Failing this it's time to get a locksmith or simply drill the lock cylinder out .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better