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Door Panel Removal for W111 Coupe

This is intended as documentation of my own repair jobs and I do not accept any liability for damage, injury or death caused by anyone who chooses to follow these instructions, meaning you're responsible for your own actions. As with any auto repair, there is a risk of danger to yourself, your vehicle, garage, home, and property so please take any and all safety precautions before beginning. You should always wear protective gloves, eyewear and other protection when appropriate.


Tools and equipment needed:

  •     Phillips head screwdriver
  •     Stubby or angled Phillips head screwdriver
  •     Trim removal tools, nylon or plastic (I bought these from Harbor Freight)
  •     Buy or make a tool out of heavy gauge wire, bent to an L shape with about 1-1/2 inches left on one end. This is used on the vent window crank.
  •     Lubricating grease
  •     Penetrating fluid
  •     Silicone spray lube


For this tutorial, I am disassembling the passenger side (US) door. Also, some things may be done in a different order, especially disconnecting the various locks and handles, but some things must be done in a specific order, but you will figure out what works best for you after you've performed the task once. There are several types of fasteners used throughout the door card, so be sure to lay the loose screws and bolts with the parts they go to so you don't get confused or loose pieces. I have a wide area set aside next to the vehicle where there is no foot traffic to serve as my workspace.


1.    Chrome door end caps: Starting at the front of the door, the end closest to the hinge, begin by unscrewing the small screws that hold the chrome end cap in place. The second to last screw near the bottom will require either a stubby Phillips head or a bent angle screwdriver to remove as there is little space here. The end cap may be adhered in place by a type of putty or may be slightly fitted under the door weather seal, but you can simply pry it up and away using your hands. Move to the back edge and remove the similar chrome plates, starting with the one at the top as it overlaps the lower piece. Remove the two screws holding in the sideways "U" shaped metal trim that adorns the latch cutout near the rear of the door.


















 

   
















2.    Window crank: Gently lift the vinyl cover (black in my photos) at the back edge and lift, this will release a clip then you can slide the cover towards the wide end to remove. Next undo the screw found under the cover. Remove the handle and then remove the white nylon grommet beneath. Keep the handle near so you can easily put it back in place to allow you to crank the glass up and down to access various points to clean and lube.














   





3.    Door pull handle: Use your trim removal tools here to avoid scratching your leather door panels. Gently pry the chrome caps at either end up until they pop. Pay attention to the clips on the back and how they fit to make reattachment easier. Unscrew the two smaller bolts at the top and the large bolt at the bottom.













   






4.    Door release/opener handle: Lift handle as to exit the car, use a bent trim removal tool to slid under the black plastic cap and slide all the way around the outer edge to free it from it's bezel. Remove and then remove the bolt revealed in the center. Pull the chrome surround off.
















   



5.    Rotary vent window crank: Use your bent wire tool to locate a hole on the backside of the round black crank. There may be a small pinhole on the side facing you to indicate that the hole is just below it on the backside. The center cap will come off if you place the wire tool in the hold from the back and push forwards, forcing the cap off the front. The cap will separate from the handle along a line about 1/8th of an inch beyond the chrome bezel, look closely and you will see the seam. Once the cap is off, remove the bolt in the center and remove the entire crank handle.













   






6.    Door lock: There are two small flat caps on either side of the flip lock that slide out to reveal a screw beneath each one. If you have trouble sliding them, place something hard like the edge of your plastic trim removal tool against the inner edge and push outward until it releases. You may want to put painter's tape over your leather in this area to protect it from damage if you must use a tool. Remove the two screws beneath and take out the chrome bezel.














   





7.    Upper leather door cap: Along the top edge of the door is a piece of trim that has a thin chrome strip running along it's lower side. You only need to smack the back edge with the palm of your hand to pry the four metal clips loose that hold this piece in place. Work your way towards the front if not all pieces were loosened. If you find plastic clips then your original metal ones have been damaged in the past and replaced. If a metal clip comes off and stays in the door, you can squeeze it together and lift it out, then place it back in the trim panel and rotate to lock it back in place. This is a good time to apply leather cleaner and conditioned to the back edge of the leather trim that you can't normally reach when fitted.











   








8.    Door card removal: Removing the door cap reveals four small screws along the top edge of the door card. Unscrew these and then you will notice that the door card is now only being supported by a chrome strip at the bottom and lower front. Simply life the door card from this channel by pulling up and back at the same time, paying attention not to catch the door card on the handles or lock. Set the door card aside sitting flat on it's back, this helps prevent warping.
















   



9.    Clear film: Remove the plastic moisture barrier sheeting and set aside without tearing it.



















The best thing to do now is to start flipping the locks, door releases, cranks, etc., to get a really good idea of how everything works inside. The driver's side door lock will not lock unless the door is closed to prevent you from locking your keys in the car. You can temporarily replace the window crank to operate it enough to move the glass up or down as needed. The vent window crank is about the only area that you can't lube easily, but if you look carefully you will see many places that can be cleaned and relubed. Start by using a penetrating fluid anywhere that seems corroded or is sticking. Scrape old dried grease from parts, especially the rollers and guides where the window mechanism attaches to the bottom of the glass. Spray silicone lube along the front rail guide for the glass, this will help it slide down easier but won't get your glass greasy. On the back edge, be sure to observe how the rail slides along a U-channel with a fair amount of friction, grease this area liberally with your heavier grade lube grease. Grease the areas where the rods slide through rubber grommets and basically grease, spray and clean anything you can see that moves.
Some people have had success with fixing creaking check strap (that long metal bar at the front of the door that keeps it from flying all the way open) by packing the rubber end caps and strap area within the door liberally with grease. I tried this with great success on my passenger side and reasonable reduction in creaking on my driver's side. A semi-permanent fix until you can have them replaced.













 





Bracket for window rollers.



















Window crank w/ knurled attachment point (upper left) and spring for window.

 

















Door release handle.



















Door lock.

 

















Door release and lock rods at the rear end of door near latch.



















Exposed door panel with original factory sound deadening material visible.

This is a great time to replace sound deadening material that may have fallen off the inside panel of the door. It's also a good time to either replace various weather strips or to at least inspect yours. You can also spray some protective coating to the inside lower portion of your doors to help in rust prevention.

Reassembly is the opposite of assembly with a note that the upper door cap trim piece should be laid in place with the clips directly above their openings, then use a solid smack with your palm from above to seat in place. To adhere the plastic sheeting, use rubber cement or silicone applied very sparingly to hold in place.





Cleaning and Clearing the Windshield Wiper Washer System

This is intended as documentation of my own repair jobs and I do not accept any liability for damage, injury or death caused by anyone who chooses to follow these instructions, meaning you're responsible for your own actions. As with any auto repair, there is a risk of danger to yourself, your vehicle, garage, home, and property so please take any and all safety precautions before beginning. You should always wear protective gloves, eyewear and other protection when appropriate.

(No photos on this one just yet.)
On early US market cars, the wiper system includes a novel way to release wiper fluid onto the windshield. At the lower left side of the footwell is a foot pedal with a metal ring lever and a rubber conical bladder beneath it. When pressed with your foot, the metal ring activates a switch that causes a single swipe of the wiper blades. When the ring if almost fully depressed you will feel resistance from the peak of the rubber bladder that pokes up through the opening in the ring. Pumping the bladder will create a vacuum that causes windshield washer fluid to be released via the nozzle on the fresh air inlet cowl. That's the theory anyway...

In reality, the system almost never functions because of age, neglect, or a combination of the two. Here's some steps I took to get my washer system working again. Remember, this isn't simply a convenience but an important safety feature since we all need to see the road.

Some things to consider before beginning this repair:
» If your rubber bladder is totally rotten you will need to find a suitable replacement or be ready to spend some serious cash as the switch is almost impossible to find in NOS condition. Parts cars usually suffer the same or worse condition to the rubber. You can add a later style foot switch which is more commonly available, it has a black, textured solid metal circle that totally covers the flat rubber donut beneath, there's no rubber nub sticking up.
» Most people simply choose to fit an electric pump to the wiper fluid system that is either a stand alone switch or activates when the foot switch is pressed. My solution is for those who want to maintain the original switch, or need a quick fix in the meantime.
» Repair the rubber bladder first since the silicone used will need a day to set up and you will need the bladder working to test the other components. If you're the lucky sort, this might even fix your problem altogether. See part (i) for instructions on how to also seal the reservoir cap, do this a day in advance also if you feel it will be necessary.


Tools and supplies needed:

  •     Extra length of same size hose, rubber is ok
  •     Thin uncoated wire
  •     Flat head screwdriver
  •     8mm socket and wrench
  •     Silicone sealant (I chose black)
  •     Fine grit sandpaper
  •     Small funnel



I jumped around the different components troubleshooting but you may be able to narrow the culprit and skip some of these steps by taking a close look at your various hoses and components before starting. Be sure you have wiper fluid or water in the fluid reservoir before beginning. Do not maintain tap water in the system as the scale and minerals will soon plug the system up again.

    a)    Remove the switch from the footwell by first unbolting the top and bottom bolts, retaining their washers. You may need to push carpet or flooring material out of the way to see them both. Mine had 8mm bolt heads so I used a small socket with an extension to reach easier.
    b)    Pull the switch away from the floor and remove the electrical connector. Remove the clear hose attached to the side of the switch. Use a flashlight to try and determine if you already have fluid in the line and have a cup or towels handy when you disconnect it. Mine was dry as a bone.
    c)    With the switch out, find the nut on the back and remove it. This will let the rubber bladder come out and you can see it is open in the back. Let the metal disc that holds the bolt fall into the bladder or carefully pull it out if your bladder is still very supple, but it's less risky to just let it fall inside. Rinse the inside of the bulb out a few times to clear it of any powder that tends to accumulate from the soaps and calcium in the water and fluids from years past.
    d)    Take a toothpick or fine wire and ream out the opening of the metal nipple that you removed the hose from. Find a piece of fine sandpaper and gently sand the outside of the metal nipple until all dirt and corrosion is gone.
    e)    Squeeze the rubber bladder and examine all sides for cracks, splits or damage. Apply sealant to the bottom where the metal bolt plate seals against the rubber, and center it in the hole again. Have an assistant compress the rubber bladder for you to push the bolt through the main backing plate so you can reattach the nut. Coat the bladder in all damaged areas with the silicone sealant and let it sit overnight before testing. Be sure to also seal around the nipple base. In my case the metal nipple broke off leaving only about 1/8th of an inch to work with, so I added a rubber hose extension that I spliced in with another vacuum line connector and sealed it all up with the same black sealant.
    f)    Reattach the switch to the floor but do not connect the wiring, just the hose. This lets you test the system without the wipers going off or the need for the car to be powered up. Test the system by pumping the bladder with your foot or hand, keeping in mind it needs to be primed the first time and may require several pumps to achieve. It is useful to have someone under the hood to let you know if any fluid is moving up the hoses.
    g)    Start checking the condition of all hoses leading from the switch, and also from the reservoir to the nozzle. Use a flashlight held on the backside to show you if there are any particles or blockages. If so, and you can replace the hose, do so. If you cannot remove it, pour some soapy water in with a small funnel and let sit, failing that use penetrating fluid, or your preferred cleaning solution followed by a blast of compressed air to clear the line. If the lines are all clear, continue on.
    h)    Go under the hood and observe the reservoir cap while having someone press the bladder for you. Alternatively you can remove the switch again from the floor and attach it to the reservoir directly using a second hose you cut just for testing purposes. You should be able to observe a small ball moving inside the check valve that is incorporated into the reservoir cap. If it doesn't move you will want to clean it. Detach the two hoses from the reservoir cap then remove the cap by twisting 1/4 turn. The cap should have a hose attached to the bottom that reaches the lower portion of the reservoir.
    i)    Soak the entire cap in a soapy water solution and then try to move the check valve by blowing air through the lower connector. The connector tips are marked with P on the bottom one (for "pump") and D for the top one, something in german no doubt. If it still doesn't move, remove the "straw" that connects to the very bottom of the cap and sits in the reservoir. Push a coat hangar sized wire into the opening and force the ball and spring upwards to free if sticking. You may also spray penetrating fluid into the check valve and let it sit for a while before rinsing and testing.
    j)    I noticed my cap was leaking slightly around the pressed metal cap on the top, the one that looks like a tiny soda bottle cap. I used flowable silicone windshield sealant on those area so it would flow in and fill the small openings. I also applied it to the seal where the check valve connects to the metal cap. Allow to dry overnight before testing as putting air through it too soon will only blow out the silicone you just put in.
    k)    You can test the check valve by itself off the reservoir to make things easy on yourself. Just remember to blow air through the bottom connector to get fluid to come out through the top. I also noticed that the system is easiest to operate and test when you use fluid, not just air, so let the bottom straw sit in a cup of water so it draws fluid. If the check valve fails to work you may need to order a new cap from the Classic Center. This is a good time to replace your reservoir also if it is showing signs of age or leaks.
    l)    Check the nozzle by detaching the top hose from the cap and filling with water using a small funnel. Be careful not to drip water on any sensitive electrical components that live in the same area. You may find it easier to get water into the small opening if you first squeeze the hose nearer the firewall and work your way out, ridding air from the hose, then as you pour water in let go of the hose so it sucks the water in. Blow with the pedal or your mouth to force the water through the nozzle. You may see nothing, one open spot or both may be working. If only one or none function, continue on.
    m)    Take a very thin piece of wire, small enough to fit into the holes in the nozzle,  and poke them in to clear any fine particles. Work it around and as far in as you can. Note at this time that the two nozzle openings are actually contained inside small ball joints that you can adjust to focus the spray pattern where you want it. Once you clear the system you will want to come back with a wire or awl point and pivot the ball joint to the desired position. If you can remove your clean-air shroud to access and remove the nozzle, it will make things easier, but do not pull the nozzle off unless you have gained access to the bottom side because you need to be able to press the hose back on the bottom. To remove the nozzle you need a flat head screwdriver for the top and a wrench to undo the nut on the bottom side.
    n)    In my case the nozzles were cleared by this time and my system worked... for a few seconds until the driver's side clogged again. I cleaned again with the wire but the same thing happened again. I finally purchased a small inline filter used as a small engine fuel filter, sold at auto parts stores for about $3 each, to filter these small particles before they reach the nozzle and I have had no further issues.




Rearview Mirror: Replace Glass, Adjust Tension for Loose Mirror

This is intended as documentation of my own repair jobs and I do not accept any liability for damage, injury or death caused by anyone who chooses to follow these instructions, meaning you're responsible for your own actions. As with any auto repair, there is a risk of danger to yourself, your vehicle, garage, home, and property so please take any and all safety precautions before beginning. You should always wear protective gloves, eyewear and other protection when appropriate.


Tools and equipment needed:

    •    Flat tool to pry bezel off
    •    Flat head screwdriver for adjusting tension (if mirror is loose on stalk)
    •    Pliers to compress mounting spring
    •    Balls of steel (needed for courage to yank your mirror out)
    •    #0000 grade steel wool pads (for cleaning chrome and your steel balls)

Follow these steps:

(Before beginning, realize that there are two pieces of glass within the mirror housing. The outer piece is clear while the mirror itself sits behind this piece and is what actually pivots when you flip the night/day lever on the bottom.)

Remove Mirror Unit: Grasp the mirror unit firmly as close to the base as possible, where it mounts to the roof. This is where you need to use your "balls of steel." Hold firmly and pull with much force downwards and towards you at the same time. The mirror unit it attached to the car by way of a cylindrical spring that forces a peg on each end to seat into the mount. By pulling down you are simply compressing the spring so that the mirror can be removed. Spray the spring ends with penetrating fluid and set aside.


















Spring cylinder shown with compressable tips at each end.

Remove Bezel: Find a tool that is flat but sturdy. I found that my nylon trim removal tools were too thick to fit so I ended up using a spreader for butter and the like. I chose to start at the top so if I marred the mirror housing it wouldn't be as noticeable here as from below, which is more visible to passengers. Fit the flat tool between the outer bezel and the bent tab, there are two tabs on the top and two on the bottom. Gently press until your tool separates the bezel from the housing and slide along towards the tab until you can release it. It is a short tab so you don't need much to get it loose, and once you get one loose do the other tab on the same side.  Once both tabs are freed hold the housing in your hands and simply pull the bezel off. NOTE: Be careful here as the inside bits will probably come loose and you don't want to loose anything or drop your mirror or glass.



















Remove Mirror Glass: Lift the mirror glass out and on the back you will see a metal plate with a clip and a spring attached over a paper scuff guard. The clip holds the plate to the mirror while the spring provides tension so the night/day feature can operate. If you are replacing your mirror glass this is the time to remove the clip and backing. retain the paper scuff guard so you don't scratch your replacement mirror. The spring should stay attached to the metal plate. Pay close attention to how the flat black plastic flip tab for the night/day feature has two small wires that are bent to fit up into the bottom of the metal plate so it will move the mirror glass when the tab is flipped.




































Adjust Tension: Locate the flat head screw type adjustor visible once the mirror glass is removed. You will see there is a small spring behind this so as you tighten the screw head the tension will increase (making your mirror more snug) and loosening it will make the mirror more "floppy" in case you want to play a nice April Fool's Day joke on someone. Test your adjustment before you replace the mirror so you know it's right, tightening too much will have almost the same effect as a loose mirror so don't overdo it.


















Tension adjustment screw with day/night flip tab below.

Clean Everything: The inside of my clear glass was very dirty from years of being sealed up so I took the opportunity to clean both sides thoroughly before reassembly, taking care that there are no fingerprints or dust inside, you will see contaminants every time you look in your mirror. Next use #0000 grade steel wool pad to clean all the metal chrome bits to shine like new. Many have been surprised that they no longer need to re-plate their chrome after a cleaning with steel wool, but only use the extra fine stuff to avoid scratches. Use computer duster to blow off any remaining dust and you may even want to wear latex gloves to prevent fingerprints during reassembly.

Reassemble Mirror Housing: Set the mirror glass so that the metal plate seats on the flip tab properly and flip the tab back so the mirror is positioned as close to the front as possible. This helps you with alignment. Next, keeping the mirror glass in position, place the bezel holding the clear glass in place by first seating the bottom metal tabs in their slots, then the top ones. If you are having trouble getting the top tabs in, use your flat tool again to work your way around the tabs lifting them into place. You can also press down slightly on the mirror housing to allow the tabs to lock in place. Inspect for dust and fingerprints, take apart and clean again if necessary.

Reattach Mirror to Car: You're going to need your balls of steel yet again for this step. You already sprayed the spring with penetrating fluid so it has now had time to work and loosen the spring up a bit. It's common for the spring to become corroded if any water has entered through the top of the windshield and soaked into the area of the dome light and mirror base. Use a pair of pliers to compress both sides towards the middle in order to loosen up the spring. Then place some grease on the ends and also on the base where the mirror mounts to make things slide easier. It's still not going to be easy though, so there are basically two schools of thought here. The first is that you align everything up with the mirror directly below the base and then pound the base with your closed fist in an upward motion. This never worked for me and I was afraid I'd break the base. Instead I tried another method, I set one end of the spring tip in it's place with the other side hanging down, then using a thin flat screwdriver I pressed the other spring tip inward enough to allow me to push the mirror unit up and lock it into place. Be very careful here and do not get frustrated, it will likely take several attempts and you may want to take a break to avoid making any mistakes like using a hammer to pound the base in which puts your windshield at risk. Likewise, if you're pushing the mirror up and away from you, you could push it into the windshield and crack it. Aim all your movements away from the windshield.



















Mirror base at interior roof of car. 





















Repaired mirror at top, old crusty mirror below.

If you need replacement glass for your rearview mirror you can contact the Mercedes-Benz Classic Center, source one from a parts car if it's in good condition, or have a glass & mirror shop re-silver it for you. Re-silvering generally costs around $40-80 depending on the shop and your geographic location.


Good work! Now go make a sandwich or take a drive and watch the word pass you by.




Sealed Beam to Halogen Headlight Conversion

This is intended as documentation of my own repair jobs and I do not accept any liability for damage, injury or death caused by anyone who chooses to follow these instructions, meaning you're responsible for your own actions. As with any auto repair, there is a risk of danger to yourself, your vehicle, garage, home, and property so please take any and all safety precautions before beginning. You should always wear protective gloves, eyewear and other protection when appropriate.

Tools and equipment needed:

  •     Hella H4 halogen conversion kit (x2) Part # 72146
  •     Screwdriver with head to fit headlight bezel screw
  •     Thin blade flat head screwdriver
  •     Bulb grease (optional)
  •     Red grease or similar for anti-corrosion


For this tutorial, I am replacing my factory sealed beam headlight bulbs with modern halogen units that keep the OEM appearance. I chose Hella brand because they use a glass lens with a metal reflector, no plastic anywhere. The kit I chose came with the H4 halogen bulbs. I bought mine for $49.99 each locally but I have seen them as cheap as $27 each online. This DIY refers to the driver's side (US) headlight assembly with two round sealed beam bulbs, but the same instructions apply to both sides on US cars. European lenses will be different and are not covered by this DIY. For the Mercedes W111, you will need the kit that replaces 5.5-inch or 5.75-inch sealed beam units which is Hella part # 72146 (I've seen both measurements used but they are the same kit, I think the difference in measurement is whether or not the curve of the lens is accounted for). You will probably only see two versions of the kit, the other replaces 7-inch sealed beam units. Since I was only doing the top bulb, I chose the hi/low kit from Hella, but if you're also doing the bottom sealed beam, buy two of that kit as well (also in 5.5-inches).













   






1.    Remove the chrome headlight bezel by first unscrewing the single screw at the bottom. Pull the bezel out at the bottom slightly to free the bezel, not very much at all since there is still a clip holding it at the top. Next, lift the bezel upwards to release the top clip from it's holder. Apply a small amount of grease to all sides of the clips, this will make installation and removal next time easier and also prevent corrosion to the clips from spreading, which can weaken them and cause them to break off. They cannot be easily refitted or replicated.











   



























2.    With the bezel removed, a secondary thin metal bezel that holds the bulb itself in place is revealed. There are three screws to remove, but before touching any of them have a look at all three. Near two of them there is a second screw, you will only be unscrewing the three that are the same size with the smaller heads. Unscrew them starting at the top and then each side, but be aware that as the bezel loosens the bulb will be loose too and you need to hold it in place with your hand so you don't drop it. It will still have the connector attached but don't trust this to hold the bulb, nor should you as the weight can make old brittle wires break apart. Set the bulb and bezel aside.

















   




















3.    Install the H4 halogen bulb in the new headlamp unit but only hold the bulb from the back, never touch the glass portion with your bare hands. Oil will cause it to explode once it gets hot. The bulb only fits one way as it has three ears that must fit into recesses on the mount. Clip the wire clip in place and put the rubber collar on the back, taking note to fit the three bulb blades through the openings properly. Once in place, give the rubber collar a solid push between the blades and around them to help it seat properly. This keeps out water and weather so you want it sealed as well as possible. Apply a small amount of bulb grease to to bulb blades to aid in conductivity and ease removal next time. Plug the connector into the back of the new bulb and then refit the whole assembly into the mount. Check the text on the front of the bulb to figure out what part is the top, then align the tabs on the outer edge with those on the mount for proper fitment. Replace the thin secondary bezel to hold the new unit in place. Refit the chrome bezel and don't forget to tighten the screw at the bottom. Note the decal on the new unit stating that it may not be legal to drive with this item in the US, so of course I took mine back off and hid them in the sock drawer. :)














   





4.    Test your lights by turning on the dash switch and then by pressing the "brights" foot switch. If there's any problems check your connections, ground wires, and finally, be sure your new H4 bulb itself isn't faulty. You're now ready for safe nighttime motoring!

















(L) OEM sealed beam unit.  (R) New halogen unit.

End of job notes: I was pleasantly surprised to see that the new headlight actually sticks out further due to it's cylindrical, rather than domed, shape, which gives the car visibility when viewed from the side that it didn't have before since my car doesn't come with side markers. Now I don't have to worry as much about someone knocking the front of my car off as I nose out to see traffic.




Brake Light Pressure Switch

This is intended as documentation of my own repair jobs and I do not accept any liability for damage, injury or death caused by anyone who chooses to follow these instructions, meaning you're responsible for your own actions. As with any auto repair, there is a risk of danger to yourself, your vehicle, garage, home, and property so please take any and all safety precautions before beginning. You should always wear protective gloves, eyewear and other protection when appropriate.

Symptom:
Brakes would only illuminate briefly when pedal was pressed and held, would not remain lit.

Part location:
Pressure switch is attached to the side of the brake master cylinder, on my '62 W111 it is attached to the firewall on the driver's side (US, LHD).

Parts needed:

  •     Brake Pressure Switch (Cost, approx. $15. Part Number #113945515H).
  •     Spade/bullet connectors.
  •     Length of wire.
  •     Wire cutters.
  •     Brake fluid, appropriate type for your car.
  •     Solder (optional).
  •     Shop towels to catch brake fluid.



Tools needed:

  •     Wrench to disconnect battery lead.
  •     Wrench to fit switch nut (sizes can vary on original and replacement parts).
  •     Wire stripper.
  •     Crimpers and/or soldering iron.



Tips:
Have all parts and tools ready as some brake fluid will likely seep out through the hole left open once the Pressure Switch is removed. Fluid loss will be minimal if done in a short time.
Sometimes the Pressure Switch can be made to work if you press the end of a coat hangar or similar flat ended thick wire into the hole on the exposed end when removed, you will feel a metal diaphragm within giving way as you push and work the material back and forth. Following the directions below, reinstall and test your brakes. I still recommend replacing with a new switch as this is likely only a temporary fix.

Warnings, precautions and disclaimer:
Disconnect the negative lead to your battery before doing any electrical work, or work near electrical components, in this case, you are working very near the battery so even with it disconnected, be sure not to lay any tools, etc., across the terminals. As always, this is intended to be some guidance for you or your mechanic to diagnose or make a repair, but I am not a mechanic and therefore do not and cannot accept any responsibility or liability for the work you choose to undertake on your car. You alone are responsible for any injury, damage or worse that may occur if you choose to work on a vehicle using this, or any other, information. Wear gloves, eye protection and observe all common safety procedures.

Step by Step:
1)    Disconnect your negative battery lead.


2)    You will need to determine if your Brake Light Switch (electrical, replacement PN #0005453509) mounted beneath the brake pedal is faulty, or if the Brake Light Pressure Switch located on the brake Master Cylinder (PN #113945515H). Test the Pressure Switch on the Master Cylinder (Photo #1) first by pulling off the Bakelite connector from the Pressure Switch, then insert a short piece of wire suitable for a 12v system, that has had both ends stripped to expose the wire, into the connector making a U-shape (Photo #2). Do not touch the exposed wire ends to avoid electric shock once the system is powered up.



















Photo #1



















Photo #2


3)    Re-attach your battery lead and turn your key to "accessory", the last stop before you engage the starter. Walk to the back of your car and the brake lights should be lit if the switch you are testing is broken as the switch basically acts to interrupt the constant flow of power to your brake lights, they default to "on" when no switch is present. It is easier to test the brake master cylinder switch first as it is more accessible from above.  

4)    Disconnect the battery lead once again and then remove the U-shaped wire from the Pressure Switch connector.

5)    Place an absorbent shop towel directly under the Pressure Switch to catch inevitable drips or leak from the exposed hole. Alternatively, you could use a rubber body plug of appropriate size, but be careful not to break the tip off inside the hole.

6)    Remove the Pressure Switch using the appropriate sized wrench, or an adjustable wrench. Test the switch now if you like, as described above.

7)    You should use a small dropper to place a small amount of brake fluid into the hole on the threaded end of your new Pressure Switch, or even a stirring straw with your finger over the top to create a vacuum allowing you to lift brake fluid and deposit it into the hole. This primes the switch by removing air. Some people claim this step is not necessary but it worked fine for me with no air lock.

8)    Screw the new Pressure Switch into place, tighten it all the way down, or as far as your original switch was fitted.

9)    You will need to either make adapters for the connectors so the original bullet style pins can attach to the new switch's spade style pins, or remove the original connector and replace with one that fits onto the new spade style switch. I chose to make adapters (Photos #3 & #4). After I took these pics I removed the wire set I made and sealed them against dirt and water by using black heat shrink tubing; this also masks the repair a bit more on first glance at the engine bay.




















Photo #3




















Photo #4
 

10)    Reconnect your wires, remove your shop towel and clean any brake fluid that may have been missed, then reconnect your battery's negative lead. (Also reset your clock and be thankful you don't have a "reset proceedure" for your windows, sunroof or non-existent computers. Pat yourself on the back for driving and maintaining an Oldtimer.) You will need to be able to view your taillights in a reflection, or have a second person stand behind the car to confirm that they are working. If so, go for a drive in greater safety!
































Repair Tips & DIY

If you're extremely fortunate, you might even have one of the factory wheel cover masks to make the job go a little quicker. If you're a stickler for total originality, or perhaps facing a tough Concours d'Elegance judge, you will want to use this method to preserve the almost imperceptible feathered, spray edge that can only be accomplished with this mask.

Painting Wheel Covers:
For a clean paint job with sharp edge lines, mask your wheel centers using painter's tape then cut around the edges with a razor knife leaving tape only on the parts you want to remain chrome.Spray with the paint of your choice and remove the tape before the paint dries.

These repair tutorials (formerly hosted at MarrsCars.com can be found below):


  • Door panel- removal/replace
  • Clean and repair bulb-type windshield washer system
  • Rearview mirror- replace glass, adjust tension
  • Headlights- convert sealed beam to halogen using Hella kit
  • Brake Lights- Pressure switch replacement
Headlight, taillight and signal lenses:

Differences in taillights (W113 Pagoda info, similar for coupes). Note that aftermarket lenses will not fit the same as heat sealed OEM lenses. Most run small and you will need to glue or seal them in place.W113 Pagoda SL lenses will fit in W111/112 cars but the chrome bezel they are sealed in will not! The W113 has a flat top edge whereas the W111/112 have a curved upper bezel.

Bullet lenses are NLA from Classic Center and many suppliers. Those that you can find are usually faded amber from parts cars or aftermarket. The OEM clear bullets are the hardest to locate. We have a source for repro clear bullet lenses, contact us if we can be of service.

Tail lights (except for early 220 SE should have a rubber seal along the top edge of the chrome, as they came from the factory, but most have lost this bit over the years while changing bulbs or during a respray/restoration. Contact us if you need these gaskets. 



General Tips:

  • Do not spray water under the upper rear windscreen chrome trim, an air vent is located here to allow air flow via the headliner material perforations. Careless washing or use of power spraying can force water into the vent causing warping of the parcel shelf, unsightly headliner stains and more. Here is a photo of the area we are speaking about and here is another photo of the vent just below.


  • When you grease your chassis make sure you also lube the door hinges to extend their life and prevent creaking sounds. This is a good time to grease your sunroof rails too if your car is so fitted. We prefer ATE PlastiLube for the sunroof.


  • Question: Why is my car so slow? Answer: It's not, you're just driving it wrong. Ok, but seriously folks, we see this complaint time and time again in person and in the forums, but the issue is really that owners of these cars with automatic gearboxes, especially the less powered 220 models with the column shift, drive them like modern cars meaning they put the gear selector in "4", the equivalent of "Drive", and then wonder why they can't get any momentum on a hill start or at normal in-city speeds. Your car was designed and intended to be shifted almost like a modern manu-matic system. Don't be afraid to downshift on any start, but especially so on inclines. Ever notice your redline is extremely high on the RPM gauge? These engines love to rev, so treat them and yourself, and rediscover a new level or spirited driving that you may have not realized your car was capable of.