How to change the Emergency Brake on Mercedes Benz W245 B-Class

Have you ever experienced running after your car while it free-coasts down a hill? Or have you thought leaving the car in Park on your automatic was totally safe until you later find the car flipped over at the bottom of the hill? Well maybe it’s time to fix that little issue with the emergency brake! Might also come in handy if your hydraulic brakes decides to take home-office one day, better safe than I told you so!

Many cars have issues with the emergency brake simply because of too little use especially when you have an automatic. Simply leave it in park and it will not move, well that’s mostly true if on flat ground. The emergency brake is mechanically operated usually though the pulling force of wires and springs. When not in use this mechanism will inevitably rust in place. This is exacerbated on salty winter roads with and infrequent cleaning of the car. On the Mercedes W245 it uses basically the same system Mercedes have always throughout the last decades, except there is very unconventional Mercedes style of using a hand lever in the center-console instead of the usual pedal lever.

On this B-Class the emergency brake system was completely inoperable and nothing happened when pulling the lever. My initial thought was to exchange the cables, but after some thinking I decided to change both the brake shoes and the cables together. The job took a little longer than expected due to corrosion and some unforeseen stuff.

Preparation

I urge you to inspect the brake shields for rust before starting on this journey, because if they are very rusted, you will not be able to secure the brake shoes inside the brake rotors. If the brake dust-shields are severely rusted, you will need to get new ones. And the job requires you to detach the rear hubs in order to install them. Changing the brake shields will not be covered here.

You should also just change the rear brake pads and rotors if necessary since you will be dealing with the same area of the car anyway.

Things you might need:

  • Emergency brake cable left side
  • Emergency brake cable right side (not the same as the left one)
  • Emergency brake shoe repair kit, which includes new springs
  • (Rear brake pads)
  • (Rear brake rotors)
  • (Left and rear brake dust- shield)

Removal Procedure

To support the rear end, you need medium tall adjustable jack-stands. Start by jacking up the rear end. Use wheel chucks to prevent the front wheels from rolling. Place the rear on jack-stands, there is a clever area near the back end of the car for the stands, I also use a backup jack at the jack-point for the side I’m working on. Take off the rear wheels, and before you do anything else, get a bucket with soapy dish water and a stiff brush (like an old dishwasher brush). Then brush down the entire brake assembly and surrounding area! This is to prevent harmful brake dust getting loose and into your lungs. The soapy water will bind up the harmful brake dust and road grime so be generous and thorough with the scrubbing. It also makes the job a lot less dirty and more enjoyable.

Rear brake hub assembly
Dirty rear brake hub assembly. Note placement of jack-stands behind the rear springs.

Remove the brake caliper. Use two spanners to loosen the piston assembly. Then loosen the bolts for the brake carrier attached the rear hub. These bolts are not very tight compared to the front calipers. To relieve stress from the brake hose, use some string or zip ties to hang the caliper from the spring or similar.

Now comes the tricky part. Loosen the securing nut for the rear rotor with a Torx bit. Then you need to pull outwards the rotor from the hub. It might be frozen due to rust and seized in the parking brake mechanism. Make sure you don’t have the parking brake applied. If the rotor is frozen, tap it lightly with a hammer. Too much tapping might warp the rotor and you will get vibration while braking. I used a lot of time and force in able to pull it loose from the emergency brake. The old rusted springs ended up snapping instead of the shoe giving in. There was a thick layer of rust encapsulating the brake shoe.

Remvoving disk rotor
Removing the rotor. Use a couple of wheel nuts along with a long screwdriver or similar as lever.

Since the springs broke and the brake shoes fell off I don’t have a picture of the assembly still on the hub, but the mechanism to the cable is . This was very rusted together and was the reason the mechanism didn’t work along with a very tired cable.

Emergency brake lever mechanism inside hub.

Use a lot of WD-40 or similar rust penetrant and let is soak before starting to loosen it. Unhook the cable from the underside of the car in order to loosen the cable mechanism.

Emergency brake cable
Unhook e-brake cable

Using a plier drag out the E-brake lever mechanism from under the hub in order to get more space.

E-brake lever mechnaism
E-brake lever mechanism. It is held in place with a pin through the end of the cable. Remove the pin to loosen the cable.

The lever is made up from 3 parts. The outer lever, the inner lever and a pin connecting the inner lever to the cable. Use a punch to remove this pin in order to get the cable free. The repair kit for the e-brake usually does not contain the lever mechanism and the pin so make sure not to loose these parts!

There is one last step to free the cable. There is one bolt securing it on the backside of the hub. Here you will need an E-Torx bit to get it loose.

E-brake fastener
E-brake cable fastener on the backside of the hub.

Now the cable is free and you can pull it from the backside and the cables can be removed.

Restoration

The e-brake lever mechanism is probably rusted like mine and needs a thorough clean and lubrication. I applied some rust stabilising paint in order for the repair to last longer, but this is totally up to you. The E-brake mechanism also contains a cylinder with a small cog over it. These are neither included in the e-brake service kit and you need to reuse these in a non-rusted fashion.

Rusted e-brake lever parts
Rusted e-brake lever parts. The two cable ends on the right side can be thrown. I had to cut them since they were so rusted to the pins I had to get the pins out on the bench.

I decided to clean and repaint the rear calipers as well since they were really ugly. This is totally optional and of course the whole ordeal will take longer.

Lubricate the e-brake lever mechanism with heat resistant lubrication, such as aluminium paste or copper paste. This will make it not seize up as fast. Also lubricate the adjusting wheel on the cylinder screw.

After you are satisfied with the restoration work you can start assembling the stuff.

Assembly

Reverse from removal…. Just kidding! This might take longer than you expect, since working with the springs of the E-brake is very fiddly. There might be some tools that might make this job easier, but you still need some brute force. So take a sip of the patience tea (or hibiscus) and get going!

Start with attaching the new cable in place and attach the lever mechanism. Make sure to drag the lever all the way in so it takes up as little space as possible. This is the easy part.

new cable
New cable popping through
Lubricated E-brake lever
Lubricated E-brake lever

Now for the hard part. Check out the picture for reference on how the emergency brake is assembled around the hub. Make sure the adjstment screw is all the way in so it’s at its shortest length

E-brake shoe and springs
Assembly of E-brake shoe and springs.

This is a bit trial and error since I might not have the best method here, but I found out that you need to keep the top spring in place on both sides and the adjusting cog in place. Keep the lower thicker spring in place on only one side and slide it beneath the lever mechanism. Use a flat headed screwdriver which is at the same width as the two outer springs which will need to fit into the slots in the brake dust-shield. They have to go in vertically then use the screwdriver to turn the spring 90 degrees to secure the spring. Start by doing one end then the other. Now the e-brake shoes are under quite a lot of tension and they are totally out of place. Try forcing one side into its natural place while using a strong hook to grab the loose end of the lower spring and try reaching the other shoe. This is more tricky than it seems and it’s possible to get it all fit up and still the whole assembly to be out of alignment. Trust me you will know if it’s not aligned properly. You will not be able to use it or get the brake disk rotor on.

I must have used a couple of hours to get both side on and was quite tired after it. Drink a lot of hibiscus to not loose nerves!

A trick is to use gloves while working to spare your hands, try to avoid impaling yourself on sharp hooks, spring and your tools. Also try not to use too much force on the smaller spring since it will break easily. If you break some of the springs you will need to get new ones otherwise the wheel might get stuck while driving. This is critical and must be sorted.

Emergency brake in place
Emergency brake in place, upper section. Notice how it gits snugly around the hub.
E-brake
E-brake in place. Lower section

Now that the E-brake assembly is in place, put back the brake disk rotor, this should pop right on now that the E-brake is adjusted all the way in. Make sure there is no tension in the cable, adjust the cable at the cable clip under the car if necessary. When the rotor is back on. It is time to fit the rear calipers back on. The bolts require some thread lock and only tighten them to 35Nm.

If you are putting on new brake pads, remember to coat the mechanical moving parts with some brake pad grease to avoid friction. Use lightly and never coat the disk surface or the brake pad material itself.

Calipers bolted on.
Freshly painted brake calipers
Freshly painted brake calipers

So you thought you were done? Time to adjust the E-brakes now!

Adjustment

Start with tightening the cable mechanism under the car. When it’s tight enough so the wheels will spin with a slight resistance when the E-brake is off the cables are good. Now fine adjustment is needed with the cogs. Put on the wheels, but leave one bolt off on each wheel. Spin the wheel again with the E-brake off. If it’s freely spinning, then tighten the E-brake with spinning the adjustment cog with a long flat headed screw driver through the wheel lug hole. Tightening is done when the screw is going outwards. Use a small torch to see what you are doing. When there is a small resistance. You should be good. Now pull on the E-brake on hard. Remember the cables will stretch and settle a bit. Now with the E-brake off again, repeat the same procedure. The wheels should be not able to spin after just one click with the E-brake on when the shoes are new.

The next step is to find an incline to test with. Here usually you will find that more adjustment is needed. I really like when there only needs on or two clicks for the car to stand still when there is an incline. I had to go back and adjust a couple of times before I could find the right adjustment with the cogs. If the cogs will need a large adjustment, then rather adjust the cable under the car. Because when next E-brake adjustment is needed, it is more easy to just have the extra available adjustment for the cogs with a screw driver, for example at the next wheel change. Instead of crawling under the car and doing the cables.

Hope it was helpful. This job really sucks and in order to avoid it more times, better use the E-brake frequently so they do not rust. I have never seen worn out E-brake shoes rather than rusted out mechanism. Cables also wear out or stretch faster than the brake shoes gets worn.

Body shop W245 edition

– A tale about rusty body panels and Mona Lisa

I cringe when I see rust on on cars. It clearly shows neglect and non interest on the owner’s part. It could be as simple as lack of washing the car, ignoring stone chips or heavy use resulting in deep scratches. However car use in winter conditions where the use of road salt is common, small openings in the paint can cause large rust areas to appear quite fast and the owner can’t always be to blame. Therefore it’s more important to regularly wash the car in the winter than in the summer time. Due to the impossibility to avoid any rust appearing in these conditions, is the reason I keep the vintage classics parked in the winter time. It is very hard to maintain older cars during winter time and the rust is very pervasive into every area. So why not use a disposable B-Class during winter?

So when I took over the B-class of course it had rust after many years winter use in Norway. Luckily all of it is just surface rust, but if not attended to it can develop into holes already in the next winter. Along with the other issues on the car I needed to get this fixed before using it.

Attraction points for rust due to stone chips from the narrow wheel arches.

The B-Class has a design issue in my opinion since the wheels slightly go too far outside the narrow wheel arches and stone chips really eat away the paint on the edges as well as along the sides of the skirts. This is most apparent on the rear wheels, but also an issue in the front. This happen even with the standard tire widths. So expect the paint to be chipped away by default. The car should have really have installed some mud flaps.

I had to address all four wheel arches of varying degree of rust, as well as the area beneath the side skirts and the underside of the drivers door. There was also beginning to form rust in the drain area for the window wiper mechanism on the passenger side. I think the main cause here is winter use,, but it could have been prevented more by washing it more often to get the salt off.

With paint it’s better to do all areas you want to paint in one go since the process of masking and drying of multiple coatings take forever to prepare and do. The painting in itself is the fast part of it. Then you have the surface preparation such as rust removal and making sure it’s completely clean. There could be additional steps of applying filler and sanding to make it even nicer. With this car I totally neglected filler and sanding since achieving the Mona Lisa with this cheap car is not worth it. Remember the longer time you use on a paint job the better the result. I tried to get a balance between visual satisfaction and function. Protect the car from rust while looking nice from 1-2 meters away.

Starting out. There is a small area of rust on the edge of the door as well. And multiple bubbles on the wheel arch needs to be attended. Rust continues on under the side skirt. Need to remove side skirt to get access.
Rust is sanded away with a narrow belt grinder. Super useful tool. The black is a rust converter paint which is clear in colour but turns black in contact with rust and forms a hard coating. This can be used as a primer, but I use a thick primer anyway over it.
Masking and priming paint. After priming the masking have to be removed. To avoid edges in the paint the edge from priming should be sanded down. If not Mona Lisa, you can skip it.
Before applying the metallic paint. Move the masking out and bend the masking paper without sharp edges to feather the new paint against the old. The result will be 100 times better than sharp edges, since the new paint will never have the exact colour of the old paint.
Painted with metallic and clear coat. I used 3 layers of metallic and 3-4 layers of clear. Not perfect but much better than rust. I’m very happy with the results!

Now let’s hope this lasts through the winter. I’m pretty certain that I will have to tend to new stone chip spots in the spring, but that’s the life when they put sand and gravel on the icy covered roads to grind away my paint. Then pour salt in the wounds so the chipped paint can start top rust. Thank you so much, sincerely! Looking forward to the summer already.

So about that Mona Lisa. Close enough huh?!?!?

Funny mona lisa

Robs Out!

Engine oil and filter change on the B-Class 180CDI W245

This is the most modern car which I have written an oil change procedure about. What is the difference here compared to the older cars? To be honest not much! The only difference is the car computer needs to be told that an oil change has happened and the service interval be reset through an OBD2 diagnostics unit. The OBD2 diagnostics unit can be found quite cheap online, but make sure you get one that works for this model with the capability to reset service intervals and fault codes. Since the more basic ones can only read fault codes.

Preparation

Get the necessary parts and oil. Here you need a filter kit, which contains the oil filter element, two rubber gaskets for the filter housing and a new drain plug with a new copper washer. Make sure to not get the cheapest filter you can find, since in my experience the filter element can start to deteriorate if you have long service intervals. This car is rated at 15.000km between oil changes, but I suggest doing them at 10.000km.

Parts:

  • Oil filter kit
  • Oil: Keep at least 6L on hand- The car needs around 5,4-5,8L

Tools:

  • Jack and jack stands
  • Sockets
  • Oil drain pan

I tend to use Castrol’s oil picker to find which oil I need for any car, but if you prefer other brands then I have no objection. Anyway Castrol recommends Edge 0W-30, but this could change if you plan to use the car in more extreme weather conditions. Refer to the owners manual if in doubt.

New engine oil for 180CDI
0W-30 Oil for 180CDI

Procedure

The engine should be at operating temperature to make the draining more effective. So prepare the oil change after a trip, either back from work or after the store.

I’m always a bit shocked when checking the oil on diesels since it’s usually pure black in color after a relatively short time. This car had some time since the last oil change and the level was quite low. This did worry me a bit since the car is at 250.000km already. It is always a good idea to check the bottom of the oil drip pan for sludge and metal shavings to assess the condition of the engine every time when changing the oil. So with that in mind, hoist up the front of the car on jack stands. This car has a very low ground clearance and it’s impossible to access anything under there.

Start with locating the oil filter element in the engine bay. It is on the right side of the car just behind the turbo. It is a bit cumbersome to reach with a socket, but you don’t need any special filter tool to remove it. The access will be much easier if you have a socket with a joint as shown in the picture below. Take out the old oil filter and then move to beneath the car.

Oil filter 180cdi
Oil filter location. Use a socket with a joint to get better access behind the turbo

If you haven’t seen under this car, everything is hidden beneath plastic panels. You have to take at least 2 of the panels off to get access to the oil drain plug. The oil drain plug is also a joker to find, since it’s not where you expect it to be traditionally. It’s at the very rear of the engine far behind the front wheels. It is the most left plug on the engine block (see image).

Oil drain plug location B180CDI
Oil drain plug location on the 180CDI. You need to remove some plastic panels to find it.

I’m not sure what the plastic panels are for except aesthetics and hiding the under body. Also it can trap moisture and rust. They have some very subtle sound dampening effects and can keep some of the dirt away. Maybe it decreases air drag at high speeds? But I didn’t bother to put them back on. They were quite cracked and had a large hole due to the low ground clearance. I prefer seeing whats going underneath the car and the ability to wash off the salt underneath there especially in the winter.

Now that the drain plug is located. Start drain the oil and try not to loose the plug into the pan when opening it. The oil should drain a while until the dripping stops. Then take the new drain plug with the new copper washer and use that to plug the drain. Do not overtighten! Maximum 30Nm.

Draining oil from 180CDI
Draining oil from the 180CDI

After the drain plug is secured. Then it’s time to change the oil filter. The oil filter cap contains two rubber seals, remember to change both of them! Use a rag to clean up inside the oil filter housing for old oil. Mount the new filter onto the oil filter cap and then reinsert the filter cap into the filter housing. Tighten the filter housing to max 25NM. Over tightening will ruin the plastic so be careful.

Oil filter kit parts B180CDI
Oil filter kit parts. Note the two rubber seals, along with new drain plug and washer. See the old filter how deteriorated it is, it’s almost falling apart. Indicating cheap filter and overdue service interval. The new filter is a honeycomb structure and not a cheap paper filter like the old one.

Recheck that you actually secured the oil drain plug under the engine before you start pouring in the new oil. The car needs 5,4L to 5,8L, but there is probably some residue and the actual amount might be a little less. Start by pouring 4,5L. Level the car in order to make a proper reading of the dip stick. Then pour little by little until max level on the dip stick is achieved.

Oil pan with old oil from diesel engine
Inspect oil from the oil pan. Since this is a diesel it’s completely black. This is normal for a diesel. Also use your smell, does it smell really burnt? This could indicate overdue interval. Also check for sludge at the bottom of the pan which can indicate old oil. Check for metal shavings which can indicate bearing wear and poorly maintained engine.

Check the oil drain pan for assessing the health of the engine and if the service interval have been overdue. Luckily there were no sludge or metal shavings from my oil, but it smelt strongly burnt. Which with the low oil level may indicate an overdue oil service interval. Thankfully I switched this oil in this before doing any driving at all after getting it. The engine is quite strong and starts easy without any smoking indicating a healthy engine still. Phew!

Now the last part is to tell the engine computer that an oil change have been done and reset the service interval. The annoying wrench and reminder every time you start the car will then go away. Unfortunately I didn’t take pictures of this process, but it’s really a straight forwards procedure.

  1. Connect the OBD2 to the connector underneath the steering wheel.
  2. Select the car and engine type with manufacturing year
  3. Go on the menu which you can reset oil service interval. These can be different depending on the type of reader, but should be pretty obvious
  4. Set that oil service have been done, this will remove warnings on the dashboard
  5. While you’re at it, do a scan of error codes if any

Now you can do an oil measurement while the key is inserted and the engine is off. You can access this through the interactive computer in the dashboard through the buttons on the steering wheel. The car will then tell you if the level is OK or not.

If everything is OK and no service interval warnings. It’s time to start the engine. While the engine is running. Inspect underneath and see that there are no oil leaks form the drain plug and also check the oil filter housing for leaks. If no leaks, go for a small 5min drive. When back, recheck the dip stick level when engine is off. Refill more oil if necessary. Also recheck for leaks underneath and at the oil filter housing.

Robs out!

Changing Filters on the W245 B-Class 180CDI

There are quite a lot of filters on this car. Diesel fuel filter, air filter, oil filter and pollen filter. I will cover all of them but the oil filter in this article (the oil filter will be addressed in a separate oil change guide). You can buy complete filter kits which include all filters. I recommend doing that to save some hard earned rupies and then changing all of them in one go, they probably are all overdue anyway.

Pollen Filter

Having that dampness and weird smell in the cabin gain? It’s not always a fart. Changing the pollen filter might address the issue. It’s also the most overlooked filter on the car. Many people does not even know it exists. Especially if you have been around older cars which do not have them! There you have the good old fashioned unfiltered atmosphere straight into the cabin.

So where do you find the pollen filter? Start by opening the hood. At the plastic cover above the engine is a narrow plastic lid. Open it and there you will find the filter.

Pollen filter location W245
Say hello to pollen filter

The pollen filter is a flimsy piece of paper which you can easily swap without any tools. Mess this up and you are a clown.

Old vs new pollen filter
Can you spot the old filter?

Well done you completed 1/3.

Air Filter

Time to step it up a notch. Now you will require some actual tools. Some torx bits to be specific. The air filter is located at the top of the engine and you can’t miss it. You have to loosen the plastic cover which is held in place by torx screws all around it. Be careful not to loose the screws into the engine bay and you will never find them again.

Air filter løocation w245
Location of air filter box

You don’t have to loosen the air intake tube going to the turbo. And if you do, it’s important to get the seal completely tight again. Not so easy.

Can you spot the new filter?

Now you have done 2/3, well done. Maybe you’re not a clown after all? Lets step over to the diesel filter.

Diesel Filter

The final and hardest part. Here you will utilize at least a screwdriver. You should also consider getting new hose clamps if the old ones are rotten. In older mechanical diesels injection systems it was a pain to change the filter, since you had to manually pump and bleed the injection system for air after changing filters. Now the car will do this for you with the electronic injection system. To be honest I did zero pre-studying before doing this job and wasn’t 100% sure if this would happen, but it was no issue starting the car afterwards. So no worries!

Locate the diesel filter on the right side of the engine. It should be easy to spot. It’s a canister with two hoses going into it. Note the location of each hose, take a picture so you don’t cross them when installing the new filter.

Diesel filter Mercedes W245
Location of diesel filter.

Unscrew the hoses and beware of diesel pouring out, prepare some paper to catch the spilling diesel. You should be extra careful of spilled diesel here since the exhaust is just beneath. This can catch fire if a lot of diesel is spilled, and I don’t want you to blame me for you burning up your own car.

The filter canister is clamped tight by a couple of spring clamps which you can loosen by hand.

Filter canister secured by two clips.

After installing the new diesel filter. Start the car and inspect closely for diesel leaks. Tighten the clamps if you see seepage. Alternatively the hoses might need replacing if they have started to seep from cracks. Diesel leaks here might cause engine fire and you have now been warned!

If you managed to complete this 3/3 step, you are already at novice DIY level and congratulations! Who said fixing your car was difficult? Hardly need any tools at all.

Robs out!