Smart Fortwo Engine repair


My poor Smart Fortwo ate oil. A lot. I wont be wrong if I say 2 litres for a 1000km. It is a common mode of failure with these cars. One little plastic valve breaks and eventually your engine is busted. That, of course if you dont know it is broken. Oil rings get stuck and engine starts to consume oil.

When buying my Smart, I knew it consumed oil. I drove happily with it one Summer and when Winter came, I thought that I should do something to it. Of course problem had escalated. The exhaust manifold had  cracked, turbo gone beyond repair, etc..


Cracked turbo manifold. Some of you maybe spotted also that the wastegate actuator retaining circlip is missing.


Cylinder head, still in the engine.


A big lower block from the engine. In order to remove connecting rods from the crankshaft, this had to be removed. If those two grey plates in the center of the block was open, removing of the block was not needed. From the internet one can find that somebody slized those plates away when block was still in the engine. I did not had the courage to do that.. I also hesitated to do that when part was out. Maybe those plates has something to do with engine rigidity. So they left untouched.


Engine from underneath, after removing that block. Crankshaft and connecting rods can be nicely seen.


In the middel of engine stripping process.


Sympton of the disease. Stucked piston oil ring.


Dirt in the piston grooves.



I put new piston and oil rings in. Before that I naturally cleaned pistons and grooves.


Cleaned pistons and new rings inside cylinder block. Arrow is pointing right when watching to front from the back of the car.


Because engine was open, I took the opportunity to change chains, slides, chain tensioners and sprockets for timing and oil pump. I also fitted a new oil pump.


New and old oil pump side By side.


A new oil pump in it’s chamber. (Btw, changing it was a waste of money, it had not wear at all.)


When putting on new oil pump’s sprockets I found out that old and new sprockets were different in size. I figured out that with new sprockets oil pump’s shaft was going to rotate a bit faster than before. New parts are in the lower part of the pic. The rightmost part goes in the crankshaft. Interesting part is that it is friction mounted. So the nut which goes on the end of the crankshaft should be in the right torque! Nut also holds multirib pulley in place.


This is a little over 115 000 km used timing sprocket from other end of camshaft.

I also fitted a new oil pan, with a drain plug in it. No picture of it, sorry!


During reassembly I had at least two oops-moment. The first was when I fitted pistons back to engine. I forgot to remove that little nozzle which sprays oil to piston from underneath. Of course connecting rod got stuck to it and nozzle got severe damage. Luckily one member of the Facebook group I belong helped my to sort it out. On the right is obviously unbroken part.


Another oops-moment was when I was torqueing connector rod bolts. My torque wrench was out of calibration and I used too much force to that bolt and it snapped. When that happened I thought that game was over. How on earth I was gonna get that snapped bolt out from connecting rod? Further investigation revealed that it was not a big deal. The bolt came out with just turning it with fingers! Phew, that was a releaf! Actually, it did not went all the way off, it just stretched. The light is visible through bolt.. 🙂


Luckily I checked oil level regularly so engine did not run dry thus cylinder head was salvageable. It only needed new valve guides. I let a proper shop to do that.


Another angle of the refurbished cylinder head.



Refurbished cylinder head in its place. Manouvering in space like this is really painful!


In the middle of the process..

The rest of the job was just a hard work. In the middle of reassembly I thought that maybe I have taken just a little too big bite. Eventually all went well and I have droven my Smart almost a thousand kilometers after that major engine overhaul!


A box full of new spare parts. Worth of it is little over 1200€! In total I spend to this engine rebuilt about 1600€. Smart parts aint cheap.. So better keep my Smart in good condition from now on!



Putting Some Smartness Into A Smart Fortwo

I have been a happy owner of a 2006 700cc Smart Fortwo since last Summer. But I have been want to put some automation to it for a while. I started my endeavor to making windows open even when ignition is off. There is easy to  follow instruction on the net.

I plan to have a spesific feature which for example a coupe BMW has. When door is opened, door window automatically lowers a bit and when closing the door, window goes automatically up. I want it because every time I close the door I feel overpressure in the cabin. It seems there is no pressure relieve valve like in more ordinary cars. Windshield is the biggest window in the car and because overpressure the sealing of it get much stress when closing doors. A very common problem with Smart Fortwo is a leaking winshield. My car had it also. I think that leaking is caused by overpressure. Luckily I managed to find leakage before my control unit got wet. By the way, that control unit controls pretty much everything in this car so it really should stay dry. It is located below dashboard so it easily get wet if windshield leaks.

That window feature is not implemented yet but I have made some testing. Maybe I’ll write something about it when it is done.

At the moment I just finished a very early alpha version of the control of seat heating. A small microcontroller(Arduino) controls with relays contact pads of seat heater switches. It puts them on automatically when head lights are switched on. After 30 seconds it puts them off and they stays off until lights are cycled off and on again. Convenient! Heating time is short because heating element is so powerful.

As I want more, I equipped control system with a rotary encoder, a temperature sensor and an LCD. My plan is that user can control various variables in the system, for example heating time. And of course temperature depended heating. When environment is warm enough one do not want his/hers seat to be heatened! LCD can display temperature readings and/or how much heating time is left.

Here are some pics taken during the process:

The initial plan was to install everything here.


Started to work by removing the Safety Triangle and dissassembling it.


The journey continues by re-engineering.


The very first version of connection board.


Here one can see it from another side. I planned to use PC817 optocouplers for isolation but along the way I switched to relays. More on that later. I took the liberty to use USB-connector for connection with car’s electric system. D9 is for rotary encoder.


This is a starting point for house making to rotary encoder. Black case is from an old wall charger for Nokia mobile phone. Knob is from an old car stereo or something like that.


Here is a rotary encoder soldered in place. When I was continuing this build I realized that I should have put rotary the other way around, three legs pointing to left instead what it is now. Well, it happens to all of us..


I also had to install capacitors to reduce interference. It still needs something, readings are not reliable enough.


There is something in the mess, I rarely see a workbench which is tidy and clean. Hmm, except Quin Dunki’s bench. Her work is amazing.

Anyway, some progress has achieved.


This is my power supply. In it’s early life it served as 12V mobile phone charger. Through this I can safely use my small embedded systems in electrycally noisy car environment.


This is my new connection board equipped with relays. As mentioned, previous plan was to use optocouplers. I did not managet to get them work, maybe because of some my stupid coding error. Anyway, I switched to relays.

Those relays “push” the triangle’s buttons when commanded by Arduino. Smart has conveniently system I like very much: Pushbutton is ON-OFF state information for car’s computer instead of some resistance change. This way relays can be used to “push” buttons.

From left to right connectors are: Black: Temperature probe connection, USB: Power to my system and controlling buttons and D9 is for rotary as earlier mentioned. Temperature connector in salvaged from an old PC’s motherboard. It is an audio connector. In the future there might be coming a minor problem with D9. In the end of cable is a quite heavy connector and stiff car’s suspension combined with that weight might do some issues by removing solder joints during time. That is to be seen.


This is a starting point for facade. The white plate is salvaged from an old laptop LCD monitor.


And here we are: Casing for encoder is ready, temperature sensor(red thing) is ready, main unit is ready. Now it only needs to be installed. And it maybe need some clever programming also. Now it is only a timer ) :


This is only temporarily mock-up.


From another angle. When thinking how to install main unit on top of dashboard wisely(read: do not drill holes in that dashboard) I got an idea: Why not make a console in front of gear stick and stuff the whole system inside it? That way there is room for that earlier mentioned window-control also.

Yes, that is a good idea. But then again that means a lot of work and no automated seat heaters yet. And Summer is coming. Also, I finally want to enjoy the work of my hands. It has been a long building process. What to do? Naturally install the system. Temporarily, of course. 😉

Encoder is located beside the gear stick. Temperature sensor is on the floor, for now. Wires needs to be sorted. But it works. Hooray!


Here is a link for video

That’s all for now!





Honda Quad Starter Motor Repair


A friend of mine has a Honda quad. He told me that it’s starter motor has gave up a ghost. Naturally I had to crack it open. During dissassembly process turned out that my buddy had rolled the quad upside down a couple of times which explains the motor oil inside of starter motor. After some cleaning it was okay, except brushes which were totaled.


Especially the another one. It looks like there has been some sparkling if I interpreter those craters right. 20160302_005-craters

My friend ordered the spare parts and a couple of days later them arrived.


During the assembly process we cleaned the anchor’s contact pads with sandpaper and a cordless drill. Not worthwhile compare to the lathe, but with limited resourses one must do what is doable..


Of course test drive went south. At first it started and ran fine, but during the second flight it stopped and did not started at all. No power, no nothing.  A closer inspection told me that somebody forgot to connect the ground wire to the motor. After reconnecting the quad ran fine and we back in business. Hooray!

Golf IV Brake Pedal Switch

I have a -06 Golf IV Variant and in one day it lit some warning lights to my instrument cluster.


EPC and Engine warning light lit and cruise control not working. Naturally I fired Google up and found that broken brake pedal switch can cause all of those problems. Running Ross Tech’s VCDS’s Measuring Values for cruise control confirmed the case. As one may know, cruise control needs to know when brake pedal is pressed that you don’t fight the engine. In the link provided is info how to check (with appropriate cable and downloaded VCDS-software) if the brake pedal switch is faulty or not. When I checked mine, it turned out that one of the two switches inside that brake pedal switch did not work. So I went to a local dealer and bought a new one for 20€. After fitting that in place I cleared all the DTC’s with VCDS and measured values again. All passed!

Some pictures of the process.

Here is the old one in position.


To remove it, it has to be twisted counter clockwise a bit.


Then it can be removed.


Empty space.


In hands.





A new one.




VCDS: No braking.


Braking. When braking, last two digits in Bin Bits-section must be 1, as they are now.


Happy driving!

Changing Head Gasket for 2001 Clio

After I changed the cabin heater radiator to my ’01 Clio it was obvious that it was not enough. Overpressure in the cooling system was still a problem.  After driving, even if the car was not started in 12 hours, there was still so much pressure in the coolant system that if one opened it, a loud psssshhhh was heard. Next thing to do was to change a head gasket. Here are some pics of the process.

This was the starting point.

And some progress.


Cleaning cylinder head with sandpaper.


Engine bay, top of the cylinders cleaned.


Old gasket was a bit worn..


Closer look.




Fitting a new one..


Tightening order.


After this point I kind of forgot to take pics.  But repairing succeeded and there was no more overpressure problems.

Sail on!

2009 Mini Fuel Leakage

A friend of mine was on a holiday trip with his friends. They were going through the city I live at the moment. Their -09 Mini decided to burst some fuel on to the road only a couple of kilometers away from the place where I stay. 

First inspection showed nothing. But when we started the engine, the problem was clear: Pressurised rubber fuel hose had worn itself out towards the other hose and fuel was literally bursting out. It was Sunday and there was no place to go to get a spare part. And if shops were open, of course they had to order the spare part, I guess. We got an idea: What if we put some copper tubing into the broken area and secure joints with hose clamp? A quick Google search revealed that Mini’s fuel pressure is 4-6 bar. A reference call to a friend of mine confirmed that our idea was worth trying: The same trick has worked with a Mercedes, which has fuel pressure of 9 bar. My friend suggested that we should put two clamps per joint, total of four clamps. By doing that there should not be any problems. We managed to find some copper tube and hose clamps, and voila!


Fixing parts, or what is left after the repair.


Fixed! A friend of mine showing the results of our work.

The replacement part could be quite expensive, those proprietary connectors smells like a good amount of money..


It was a kind of difficult to reach but we managed to get it right.

Testing revealed no leakage. Success! Friends could proceed their trip. I suggested to the owner of the car that he should order correct spare hose as soon as possible.

Later on I got a message from my friend that no leakages has found. Good!

1999 BMW E36 Compact Blower Resistor

I was at a longish trip with my E36. Weather was a bit rainy. During way home my blower decided to quit. At first I did not recognize it but eventually next day I got it: Blower was not working. (Or almost not working, highest speed was okay.) This is very common symptom when blower resistor has broken up. Blower resistor changes the speed of blower. Location of this resistor varies for every manufacturer and even in different models and year, so at first I had to locate it. I looked inside under the both sides of dashboard – no luck. Then I got a hint from one of the forums: Pop up the hood and tear off some parts below windscreen at the engine bay. Couple screws and panels later I was back in business: long missing resistor was at sight. At first I had to remove pollen filter, resistor was under it, very near of the blower itself.

And then I realized why resistor was given up: Pollen filters was so dirty that practically no air could go through and thus resistor was not given any cooling airflow. Raining mentioned at first part of this post was the final key, it had blocked filters with water and dust..

Shiny new ones and old ones for comparison..


Location of pollen filters, new ones fitted for clarity. Blower resistor lies down below the another (right in this picture) pollen filter. Connector was a bit tricky to get back, wire was quite short. But I managed to get it 🙂


Broken resistor looks like this. I decided to try repair it, only problem seemed to be that small metal spring which has lost contact. (Two solder points between dark and light green areas.)




.. And progress. 35€ saved! Soldering was bit challenging so there is so much solder that next time in hot situations it may not work as planned. (It is a thermal fuse). (If you do this kind of soldering you need a good and capable soldering iron, there is quite some copper to be heated up.. )

But in our country very hot weather is rare occasion and I plan to change pollen filters more often than previous owners.. And there is always the another end of spring, which is untouched.


General view. At this point I drove a couple of days like this and tested how blower resistor worked. Everything seemed to be fine, so I proceeded. And I forgot to do another maintenance:  put some oil to blower bearings, at winter they tend to make some noise at higher speeds. Bummer!

But, on the other hand, now I know how to do it, so it is not a big deal. I just have to remember to dot it before winter..


Panels waiting to be fitted back.


Same panels upside down.


Almost ready.


And finally finished!