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Vacuum door actuator repair

8303 Views 1 Reply 1 Participant Last post by  NE2I
Hi Folks
I thought Id start my membership to this forum with a bang.
Ive made an instructional on repairing those pesky vacuum door actuators.
I own a 81 300D and of course I had non functioning door locks. Actually they
were disconnected when I purchased the car. Yep they were leaking....
I traced the leaks to the trunk, front passenger rear driver and the master
switch! Thats alot of money in actuators! I looked around the Internets and found an allusion to a much cheaper fix. No instructional tho....

Auto part

A pic of the part with part # I bought this at

I wont show you how to remove the actuators... Im sure they are covered somewhere out there in the forums.

Plastic Tool accessory

A pic of the trunk actuator. This is the only one you will have trouble with as
the spring assembly is captured by the metal on the actuator rod. A
possible fix is grinding one side of the pressed area and using a E clip of proper size for reassembly and some JB weld I didnt have to mess with it
because I bought one on ebay. Maybe ill tackle this one on another tutorial.
We are talking about doors here...

Next up is removing the plastic cover and rod clip. I used my hand and banged it on the desk. Grip the plastic cover well. It'll come and the plastic is
of good quality. Don't be afraid to use some force.

Leg Hand Footwear Human leg Flesh

Here is a pic of the actuator with the cover off and the offending seal The rod clip just pops off....

Auto part Pipe

The old seal is removed by pulling the rubber off the base. not too difficult.
mine came off in 2 pieces. The fun begins when installing the new seal.
The seal isnt really made for this application. Its a electrical connector cover!
but its the right size for this job and its cheap! About 2$ each! Its pretty thick
at the bottom and will really hold well in the base slot. The small end does not have a hole cut. I used a jewelers screwdriver to poke a hole in the end from the inside. You will need a little bit of lube and effort to get the new seal on the base. I would'nt use anything petroleum based. I just used a bit of water. It isn't easy and will take some effort to get it on there but it'll be worth it....

The reward!

Auto part Vehicle Suspension

And a pic of the rod clip and cover back on the actuator.

Auto part Tool accessory Machine

Test by sucking on the unlock side (yellow green) and reinstall!

My fuel door lock was not working but I found it was simply rusted in place.
removed it and sanded the rod and new lube made it work fine. It looks like
it should also work for this fix.

As an additional precaution I changed all the rubber T fittings in the car.
In troubleshooting they all came off pretty easy and were cracked. Cheap insurance. I also lubed all the door and lock mechanisms when I was in there. Makes them work so much better with less drag and faster operation.
My master switch was bad so I changed that also. Sorry no way around that one as of now. More experimentation is needed!

**BTW every bad actuator on my car failed on the unlock (yellow green) side.**

That is because the boot is exposed to the elements. If your actuators
are failing on the lock side (yellow red) this will not help you and your going
to have to pay the big bucks for a new one..

Enjoy and tell me what you think.

Edited to include pics Yay! figured it out....
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Added links to pics

So you can tell im a newbie! My pics didnt upload so I added links to the photos. Sorry when I figure it out ill re edit to include them.
***Flash Figured it out!! Pics Added!!!***
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