The B-Class has some extra headlights mounted. Not only are they ugly, they are also completely useless when not working! I’m unsure whey they are put there in the first place since the B-Class has quite good original headlights. Also there is some weird power drain on the battery when the car is parked, and it could be part of the culprit. This must be removed promptly!
Following the spaghetti wire into the car and under the passenger side floor is the location of the battery. There a surprise was waiting, turns out the positive power for the extra lights relay is connected to the negative battery pole. Great.. We’ll remove that crap and throw out the spaghetti.
To remove the extra headlights I had to remove the grill. There were quite a lot of bolts attached into the plastic of the grill and bumper. The whole assembly job smelled of cheap. The headlights themselves are Hella and of ok quality, but the the water and coronation attracting wiring job without solder and drilling straight into the plastic of the car is not ok! It really felt good ripping the whole assembly off.
So finally after removing the crappy extra lights I could put everything back together. I’m quite displeased with the holes in my grille. Might need to replace it now. The holes in the bumper can at least be hidden behind the front number plate.
Job well done, at least it doesn’t look like a turd.
The major issue with this car which basically prevents me from driving it is a malfunctioning front window wiper mechanism. It rains quite a lot here especially in the autumn, also it’s illegal to drive without them. While the front window wipers are essential, the rear one is not working either. Side view mirrors are often enough, however the mirrors on this car are so small and “well” designed so you can’t really see whats directly behind you. So I will need to fix that one as well.
The front wipers were almost not working when picking up the car when I bought it and the wipers were stuck in a weird position. Unfortunately it was heavy rain this day and not really possible to drive without it. When inspecting the mechanism it turned out that the motor was fine, but the wiper bracket was broken due to a totally seized right side wiper shaft.
After some 2 hours of fiddling in the rain we managed to get the driver side wiper to work (barely). The drive home was quite interesting where I operated the wiper only when strictly necessary. Thankfully it worked all the way home with no fuzz.
Front Wiper Mechanism
The access to the front wiper mechanism is easily made with removing the plastic cover just over the engine beneath the front window. But first open the hood to get better access to the wiper arms. Some care here is needed so you don’t crack the front windscreen, such as dropping your tools and slamming the spring loaded wipers on the window.
Removing the wiper arms can be a challenge if you don’t know the trick. Unscrew the nut half way, then use an open ended wrench to pry off the wiper arm and voila it’s off. Once both wiper arms are removed, you can remove the plastic guard cover. It’s only held in place with 6 hex screws located at the top of the engine bay. Take care not to loose any tools or screws into the engine bay. You will never find them again from the bottom of the engine bay.
The wiper mechanism itself is easy to take off. There is one cable to the motor, then the mechanism is held together with 3 bolts. When reinstalling a used one, or refreshing the existing one. It’s an excellent opportunity to lube the wiper shafts with some oil and put some grease on the mechanism joints. Much easier than when it’s on the car.
Before reinstalling the wiper mechanism, make sure the joints are installed the correct way. Use the article as reference since there are two ways the joints can attach to the middle pivot bar. Installing them the wrong way might ruin the assembly when turning on the key. Also beware that the motor is really powerful, so don’t put your hand or fingers down in the mechanism while someone is turning the key or checking the mechanism from inside the car. Ideally the battery should be disconnected while working on the wipers.
Before assembling the whole thing, make sure the wiper mechanism works properly by turning on the wiper motor and inspect that the mechanism works without any issues and clears all obstacles under the windshield. There is some wiggle room for the bracket in the 3 mounts. Then you can put back the plastic cover.
Installing the wiper arms is probably the most difficult with this job, since it needs some fiddling and adjusting to get the correct angle. The two arms are not equal either so make sure to put them on correct to their assigned side. When aligning them, you will need to try them out and see if they have enough clearance when operating while also cover most of the screen. This might take a couple of tries, so be patient. When they are aligned, then put back the plastic covers and your are done.
The issue with this type of wiper arm design is that the wiper arms seem constantly to fight for position. If one binds or get stuck the other wiper will most likely break the other arm with a punch! A problem in older cars with more non-synchronized wipers like these is that they end up fighting for the windscreen and the wiper arms get bent, for example Lamborghini Espada.
Feels good to have working wipers again!
Rear wiper mechanism
The rear wiper motor is easier to replace. First remove the wiper arm, or if it’s broken off like mine, remove the nut. Then open the rear hatch, there is a plastic cover under there which can be removed without tools. Just use a plastic prying tool to snap it open.
The wiper motor has a plastic tube which needs to be unhooked. The plastic tube delivers wiper washer fluid to the rear window. Don’t worry, it will not leak water when unhooking it. Don’t mess up the plastic spring, otherwise you will leak washer fluid into the boot. Also unhook the power plug.
The window motor is held in place by only three bolts, and when removing these you can slide out the whole motor from the rear.
A new rear wiper blade comes actually wih a new arm as well, since the wiper blade is quite special and non-standard. It is not super cheap, buit not expensive wither. Installation is just reverse of disassembly, remember to test it and check for leaks before finishing at the end.
My experience so far with working on this car is that it’s actually super easy to work on. It seems that if a car is easy to assemble on the factory thus making it cheap, it will also be easy for the home DIY mechanic to do work on. I’m quite happy for that. Older cars are usually more complex in their build and also a bit harder to work on.
2 L Diesel with 109 hk Turbo and CVT Auto transmission. Front wheel drive, with transverse mounted front engine. 5 seats with made from fabric. Not washed in a while with a strong smell of dogs. Some broken stuff like windshield wipers. Welcome to my new 2008 B-Class W245.
“So boring and dull! How can you endure this torture?!? It looks like an egg! It’s not even a real Mercedes! Did Mercedes poop it out from Stuttgart? B for bloopers! I would turn 180 degrees around when seeing this car!”
I can hear some of you thinking this. And perhaps you have a point. It was considered quite ugly when it was first released, however I think the design have matured somewhat and is not that ugly anymore. It blends in with all the other boring cars and it’s still quite dull though. But I needed something cheap, reliable and fuel efficient for commuting to work especially during the winter. And fast before winter starts! A diesel is good since I can save around 2 kr for each liter and it’s more lean than a similar sized petrol engine. I generally don’t like front wheel drive at all, but for commuting during winter in the steep hills around here it’s somewhat of a benefit.
The car has done 250.000 km which is not little, but not super far either. I got the car cheap which means it didn’t come perfect and has a few things to sort out first. The most critical is the front wind shield wiper which is broken. Second most critical is a faulty parking brake which require new cables in the rear. There had also been drainage of the electricity of the car battery while the car was parked, however this could be due to the non-original extra lights or something with the broken wind shield wipers. Both front and rear are not currently working. The rear one not working is not required by an MOT, but it is annoying when the side mirrors are so small you can’t really see what’s straight behind the car.
Cosmetically there is some rust on the wheel arches and below one of the doors. Thankfully there are no holes and the rust can be stopped quite easily. Actually the amount of rust on this car is quite little compared to the age and mileage of such a car in Norway due to all the road salt it’s exposed to during winters. It could also do with some standard service, such as changing the oil, diesel filter, air filter and the pollen filter. Oh, and did I mention it’s not even approved for the MOT haha!! So it could potentially have some more unknown issues!! Exciting!
TODOs before it can be MOT approved is as follows:
Replace front windshield wiper mechanism
Fix parking brake
Stop rust on wheel arches and paint
Replace rear wiper motor
Engine Oil and filter change
Air intake filter
Cabin pollen filter
The summer tires are extremely worn, however the winter tires are in good condition with steel studs which is required around there. And winter is just around the corner. Will not bother to get the new summer tires until the spring. The 280CE also needs new tires and will get the priority now. I will keep you updated with follow up articles.
The W140 How To.. articles are too and far between, especially on this site. Gladly on my part (sadly for you guys…) there has been very little wrong with this car and there’s not much maintenance either since the S600 has not been used as a daily driver. The W140 appears to me as a very over engineered car with an extremely durable design. As mentioned in the review, it is quite heavy due to all the extra sound dampening and extra equipment for comfort. I have never been in such a quiet car ever. Rolls Royce is probably the only comparable here. But as any other car, it too require regular maintenance such as oil changes. So how do you change the oil and filter for the engine in the M120 V12 engine. Sounds a bit scary right?
This Mercedes model was one of the last one without the common OBD2 interface, and it is not required to a use any electronic diagnostics tool to reset some car computer during the oil change. What you need though is a lot of oil, A lot with a big A, 11 Liters to be exact. Remember to get an oil filter too, please get a good German known brand since they will last longer, not disintegrate and not ruin your engine. The price is anyway insignificant at this point. You don’t want to cheap out here, trust me.
Another tip is to get 2 new air filter elements since you will be messing with the air filter box anyway. And since they are cheap and should be replaced regularly it is a good time to change them now.
What type of oil then? Well it kinda depends on the conditions used, warm climate vs cold, harsh driving vs. balanced etc. I am using the car mainly in summer in a moderately tempered climate and use the car quite balanced. So no need for high performance or very cold weather conditions. However the engine is quite large and is quite slow to get up to operating temperature, so a thin cold start oil is probably beneficial to avoid unnecessary wear and tear when the engine is running cold the first 5 minutes.
I ended up using Castrol’s recommendation chart and it recommended the 0w-40 Edge fully synthetic oil. This is not an ad for them, but easily available here.
You will also need a special oil filter cap tool which can be acquired quite cheap from any car parts supplier. The cap is tightened to 25Nm and is nearly impossible to remove by hand. It’s also made of plastic so it can break, a new cap is not cheap. The trick here is however to get the correct one since there are hundreds of different ones. I spent quite some time to figure out the correct one without actually looking in the car and measuring. Firstly I couldn’t travel physically back then due to the lock-down and secondly I didn’t want to fiddle with the car just to find out the specs for the tool. (The oil filter cap is not visible by just opening the hood and requires removal of the air intake box). The oil filter removal tool is 74mm width with 14 slots.
Parts and tools
Oil filter (oil filter comes with new oil filter cap o-ring and a copper washer for the oil drain plug)
11L of Oil, your choice, e.g. 0w-40 fully synchetic
Oil filter cap removal tool. 74mm 14 slots
The oil removal process can be done with a oil suction pump inserted from the top of the dipstick tube and then removing the drain pan plug after, this makes less of a mess and is done in most workshops. However then you need an extra tool, so this guide will only use the drain plug method.
The engine should have normal operating temperature while changing the oil, since the oil will drain out easier, so take the car out for a drive before or plan to do the oil change straight after a trip.
Start by lifting the car up in the front and place it on jack stands in order to access the oil drain plug. Some of the w140 have plastic panels hiding the drain plug, so make sure to remove these. However my car does not have them and the drain plug is easily accessible. Before draining the oil from below, the oil filter must come out to allow better drainage. After opening the hood it can be very confusing locating the engine oil filter housing, and in fact you cannot see it unless you remove the left side air filter box. It’s well hidden below it.
Thankfully it is easy removing the air filter housing. It’s attached by two bolts and a couple of clips to the intake housing. You also need to disconnect one airflow sensor cable. Take care not to loose the intake hose clips into the engine bay which can be hard to recover, since they can come loose by themselves after loosening the air box. Loosing such a clip will make dirty air potentially enter the engine since it can then bypass the air filter.
After the left side air filter box is removed, you can now access the oil filter housing and remove the cap with the special filter housing tool. Use a joint on the socket to make the operation easier since access is poor down there. Pack a lot of paper and keep a tray on hand to avoid spilling oil when taking out the oil filter. Clean up all of the spilled oil, since it’s hot down there and we don’t want smoking and fires while the engine is running. Also use a small suction pump or syringe to get the little left over oil which lies in the house after the old filter is removed.
Then it’s time to open the bottom oil drain plug. You will need a large oil drip pan which can have at least 11 Liters. Beware the engine oil is hot and will come out with great force when removing the drain plug. Use plastic gloves to protect the skin and try to not loose the bolt into the pan when removing it. Expect about 10-10.5 liters of oil to drain out. It’s nearly impossible to drain it completely of 11 liters by just removing the plug as with most cars.
When the oil has stopped draining after 10-15 minutes. Change the copper washer on the drain plug that comes with the oil filter kit, and the reinsert the drain plug. Do not over tighten since it will ruin the threads in your drain pan. Tighten the drain plug bolt to 30 Nm. It have happened a few times over the history that people have forgotten to insert the drain plug bolt and poured in the new oil which just lands on the floor. Do not stress and make this mistake!
Then replace the O-ring of the oil filter cap with the one that comes with the oil filter kit. Many recommends giving the O-ring with a coat of engine oil before assembly. I have no idea if it’s any useful, but I did it. It gives at least some less friction when installing the cap. On most cars it’s good to fill the oil filter hosing with oil so the first few rotations of the engine will have faster access to the new oil, but on this car it is not possible at all. Pouring new oil into the housing will just drain straight into the block. Also it is not possible to install the oil filter without it being attached to the cap itself, so there is no chance here.
The oil filter is installed by popping the oil filter to the cap and then inserted into the filter housing. Tighten the cap to only 25 Nm and it’s very important to not over tighten here since it’s made from plastic and easily strip threads. And a new cap is very expensive!
Before poring in the new oil you need to know how much to add so you’re not over filling the engine. Simply adding 11 liters will most be too much. So you should always measure the quantity of oil which was drained. In my case it was slightly above 10 Liters. Also inspect the bottom of the oil drip pan, look for sludge and which can indicate overdue oil change interval and metal shavings which can indicate excessive wear in bearings and pistons. In my case it was no such indications and all is good.
Double check drain plug and oil filter cap is secured, then start poring fresh oil using a funnel to avoid spilling oil all over the engine. After you have filled the quantity you need, measure with the dipstick and inspect it’s not above maximum level. Some of the oil will need to get into the filter and you probably have to add slightly more after the engine have run a few minutes. Turn on the engine, see that you get good oil pressure, and inspect for leaks in the drain pan and around the oil filter cap. After the engine has run for a few minutes, turn it off and measure the level with the dip stick again. Add oil if necessary, but do not over fill. If too much is added then you need to remove the excessive oil with a suction tube.
Then reinstall the air filter box. Now It’s a good time to also change the two air filters on either side of the engine. No tools required here, it’s made like a drawer, like how you store your underwear at home.
Then take a short drive of 5-10 minutes, see that you have good oil pressure and that the engine feels normal. When coming back home, inspect for leaks around the oil drain plug. And remeasure the oil level with the dip stick, add oil if needed. Then you are done for another 15.000km.