Winter Hibernation

With the recent addition of a winter car, I'm able to spare this car the heavy burden of winter driving. In a way it makes me sad to part with the car for so long, but at the same time, I'm glad I'm not putting it through yet another winter. It could handle it fine, but since I now have an alternative, I just elect to invest in the car's future and not risk further salt corrosion.

Putting a car away for the winter is a process in itself.

First step, there was the scheduled service. Engine oil (10W-30) & filter, power steering fluid flush and top up with Mobil ATF. Coolant topped up and checked for low temperature resistance.

Second, vacuum out all the leaves and similar autumnal crud...

Third, the final hand wash of the season.

Washing the car at barely above freezing was exhilarating as always...

Fourth, roadworthiness inspection:

Passed fine. Brakes are okay, suspension is nearly perfect, underside is fine, wheel bearings very slightly worn in the front but still average condition. No electrical malfunctions. One lower ball joint boot was ripped, need to fix that. Power steering has a fluid leak, need to investigate that. Next year.

Emission numbers:
HC 145 ppm
CO 0.16 %
CO2  13.20 %
O2 2.55 %
These are very good considering the cat's been removed.

Fifth, last family photo before going away:

Sixth: go to sleep :-(

I can rest easy, though, because I need to go back there to take out the battery and throw in a de-humidifier. So I will see it again soon, yay.

Suddenly, Things To Talk About

The next step in diagnosing my full-throttle misfire issue was to try a guaranteed-to-work loaner EHA (Electro-Hydraulic Actuator for the fuel injection system).

The CIS-E fuel injection system is really finicky in places and although it's commonly thought you will see or smell a fuel leak when the EHA fails, this is not true in all cases. You may have a perfectly fine looking EHA with great O-rings and still you may have misfires at various RPMs and throttle positions. This is because your engine will be receiving more, or less fuel than is appropriate for the situation at hand. None of it may end up outside the EHA or the fuel lines but it is surely ending up in the combustion chamber and that would cause a misfire.

I happened to have a working EHA available, so I gave it a go in my car. It's a simple job: remove air filter casing, disconnect the electric connector on the EHA, remove two bolts that hold it in place, and it will drop in your hand. The only things you need to pay attention to: some fuel will spray uncontrollably because the fuel lines are under pressure, and the little rubber O-rings between the EHA and the fuel distributor may drop and get lost.

Sadly, switching out the EHA made no difference to the misfires I'm experiencing. I still have an idle misfire when engine is slightly warm but not up to full operating temperature, and a consistent misfire/hesitation under WOT acceleration. This is where I currently stand in the diagnosing:

• Spark plugs
• Spark plug wires
• Distributor cap and rotor
• Fuel/Air mixture
• Fuel filter
• Fuel pumps
• EHA
• Fuel pressure regulator
• Fuel accumulator
• Ignition timing

So, next up will be the fuel pressure regulator, and fuel accumulator as suggested by Dr. Greene earlier in this blog. The accumulator is not expensive, only about 100 EUR, but the pressure regulator is many times that, so I may have to wait again until I find a working loaner.


Despite the misfire problem I couldn't resist taking the car to the strip yesterday. I had beaten my friend's 560 SEC ECE in the dynamometer, and now, with him having replaced his EHA, it was time for a rematch in an actual performance arena.

Having lined up at the start, I put the gear selector in "2 B", and then back to D. This will ready the gearbox for a first gear start in a European W126 car. Consider this "launch control" from the 1980s... Otherwise the car will always start in 2nd gear, for smoothness, even in S-mode. Speaking of, I had the gearbox in S-mode, which will allow the engine to rev to the redline, unlike the E-mode which will shift pretty early in comparison.

I stood on the breaks, built some revs until the car was eager to go, and made my start. Accompanied by two(!) long black lines and some tire smoke from my cheapo tires, I made the quarter mile in 15,39 seconds. In 2011, I had achieved 15,37 seconds. As the car stands, I believe it would do under 15,3 seconds, if not for the "showy" start.

There are some US websites listing 15,2 second quarter miles for 560 SEC cars, which may be on the less powerful US version. With the misfire fixed, I believe mine could do a sub-15 second quarter mile.


And an announcement: 320 000 km, last Thursday, congratz car!

This will mean a scheduled service. This time around, engine oil and filter, and power steering fluid only.

Broke Another Mercedes, Part II: Back from the Menders

About two months ago, I had the misfortune of a Volkswagen colliding with my front bumper. Last Friday I got the car back, with the damaged bits put right on the other party's insurance.

The repair started with me requesting very specific shops for the bodywork and paint. The bodywork shop Heinonen in Lappeenranta is a family business spanning four decades and is known for top notch repairs. A friend of mine took his 1964 "Pagoda" 230 SL there for a rear quarter panel rebuild and the car ended up excellent. Thus I trusted this shop with the front wing of my SEC. For paint, I chose Nokkala just down the road. This paint shop has the same credentials, and with over 60 years of family-owned auto painting, combined with a great local reputation, I trusted them to handle my car with the respect it deserves.

Not everything went smoothly. My insurance company decided to turn lazy, and took many weeks to even acknowledge my repair claim. It wasn't until I reminded them with another message that they promptly sent approval to have the damage inspected and budget set.

With the budget in place, the insurance company took its sweet time again until the budget was approved and I was allowed to book the repairs. There was probably a good 2-3 weeks of waiting for the budget approval, and then another week until the repair date. When the repair date dawned, it was found that the M-B dealer had shipped the passenger side chrome. Fortunately the chrome is a reassembly phase part and the correct part was shipped while the repair was progressing. The repair itself would take one week from Monday to Friday.

The original rust-free front wing was straightened and painted. The bumper was fully repainted. New Bosch (OEM) corner light was installed, as was a new chrome strip for the driver's corner of the front bumper.

This is what happens to bumper chrome on Gen-2 W126 cars after decades of use. They rust from the inside outwards. This does not happen with Gen-1 cars. At least the problem is not as pronounced. As you can see here there is nothing left even of the fastening points.

Visible side of the old bumper chrome, showing the rust on the right.

New chrome that went on the car. Interestingly it had the often-seen yellow seal paint on the back. I suggested to the bodyshop that Tectyl be added so that the rust problem is avoided to the best of our ability.

Bumper is attached to this part. The stem pointing downwards here is the part that broke in the collision. This part is clearly made of a light alloy; it felt extremely light in my hand... M-B was saving weight in surprising places.

Bodywork only took a day. Paint, two. Reassembly took a day. The bodywork shop, while reassembling, had trouble locating the block pre-heater (it is in the block, near the exhaust manifold, on the driver's side) but this was sorted over the phone.

While I had the car in a skillful bodyshop, I thought I'd have them execute a repair that I had on hold ever since I paid a visit to my friend Matyas in Helsinki. He had informed me of a repair he saw coming: both my interior door handles were sagging. This is a type fault in the W126 chassis. All the cars will face it eventually.

The door handle will start hanging, first a little, then it will start hanging outside of the facia it normally sits in, then considerable slop will appear (you can even move the handle up and down) and eventually, the axle which the handle revolves around will snap. At this point the door handle is still attached to the unlock wire and thus usable for opening the door, but you must position the handle with one hand and do the door opening action with the other. This happened to me on the drivers side a few months ago; I felt an odd sensation in the door handle and the off-track movement almost gauged it out of the door. The passenger side handle was also hanging and there was some slop.

Fortunately the door handles are still available from the dealer and even online parts suppliers like Autohaus AZ. From the local dealer I got both sides for less than 90 EUR total after club discount which I would consider very reasonable.

Old picture as a reference; you can see the passenger side door handle hanging at a downward angle.

Changing the door handles was a breeze for the body shop and I was only charged an hour's work for the two handles. This was a dirt cheap fix in contrast to it being a considerable facelift for the interior and I interact with the door handles more than almost anything else in the car.

Here are pics of the car as it stands today, door handles and all.

This chrome strip used to be the only one showing rust; I now have rust-free chrome over all of the front bumper.

Once finished, I asked the repair staff what the tally ended up at. I was told "over 1500 EUR but under 2000 EUR, closer to 2000". Thus my lowball estimate of 1500 EUR was surprisingly accurate. Yay for insurance.

Fun at the Dynamometer

Last Saturday I took the car west to Kausala, about 110 km away, where the M-B club held a dyno event. Here's a video of the numerous dyno pulls we took with my car.

The car put out 213 hp at the rear wheels at 4800 rpm and 370 Nm of torque at 3000 rpm. If you're wondering about the low amount of horsepower, note that there are numerous factors you must consider:

• Dynamometers do not put out comparable horsepower readings, each dyno will be biased one way or the other.
• Dynos do not measure horsepower, they measure among other things speed and torque. Horsepower is always calculated which means dynos will use differing formulas for getting a horsepower reading.
• Dynoing cars with wet automatic gearboxes will always result in a false reading because the torque converter distorts the torque reading.
• Performance measured at the rear wheels cannot ever be reliably compared to performance measured at the flywheel due to drivetrain loss.

This is not to say my car is "actually as good as new although the dyno says otherwise". It is old and probably tired. But a 560 SEC ECE, with 300 hp from the factory, was measured at 182 hp in the same dyno, so there you go!

You can see big clouds of blue smoke exiting the tailpipe after each pull. It sure looks scary but note that no blue smoke exits the exhaust during the power band, only on overrun. We speculated that this is typical for old M-B engines and the M117 in particular; when the engine is at the top of the revband, there is a hard vacuum inside the engine. Then you let go of the throttle and the air intake closes. The vacuum state causes some of the oil in the head to enter the combustion chamber past the valve stems. I measured the oil level when I got back home and there was no visible difference. Also my car loses no oil between oil changes.

New Fuel Pumps

My last attempt at trying to fix the high-rpm misfire was changing the fuel filter and spark plugs. In addition to those, I've got new spark plug wires, the distributor cap and rotor are as good as new, fuel mixture has been verified in a machine. None of this fixed the problem: at full throttle, in a long gear, at about 3200rpm (120 kph or faster), the engine begins to misfire and no longer pulls clean. The performance just goes away.

It's starting to feel like this is a fuel pressure issue. I'm saying this because I can pull full throttle accelerations around town all day long, until I go so fast I dare not keep going. It feels like the fuel system has just enough pressure in there for normal driving, and to provide short bursts of acceleration.

All Gen-2 V8-powered W126 cars have twin fuel pumps arranged in series (not parallel, mind you). Fuel system pressure is around 6 - 6.5 bar. These V8 barges take a lot of fuel to propel at full acceleration. I have measured 6.6 bar of pressure in my car:

This is a little high, but then the pressure meter could easily have an error margin of 0.5 bar.

In any case, I'm thinking, one of my fuel pumps may be weakening, which they have a tendency to do with age. The fuel pumps provide just enough fuel and fuel pressure to get around, but not enough to really get the performance out of the engine. When a lot of fuel is needed, the supply just is not enough. The other option is that my fuel pressure regulator has failed, but since it's more expensive than the two pumps, and a fellow enthusiast declared they never fail and I'm stupid for even considering it, I'm first going to try the pumps.

I ordered two OEM Bosch fuel pumps from MB Classics in Vechta, Germany. The pumps are generic so they will fit almost any M-B from the period, in either a single pump or twin pump configuration. Part number is 0580254911 and they cost roughly 140 EUR per pump.

The pumps are shipped with connectors for the electrics and some extra fuel line bits. The latter will probably come in handy, because fuel lines are usually rusted solid...

So, come Saturday, I had access to a garage with a maintenance pit. I got down to business with the pump swap operation...

This is an old photo. It shows the general arrangement of the fuel pumps. As I mentioned earlier there are two pumps in series. After that, the fuel filter (the void in the photo), and after that, the fuel pressure regulator. Fuel inlet from the tank is in the very front of the image, on the right. Exit from the fuel pressure regulator is hidden quite deep within the rear suspension. As you can see in the photo, the frame of the left fuel pump is not connected to the big frame. I didn't notice this at the time but today installed a bolt to hold the pump in place.

From the pumps onwards until the pressure regulator, fuel travels in metal pipes. These are prone to rust and will snap if stressed excessively while opening nuts.  New ones are expensive so I had to be extra careful while swapping the pumps.

All nuts and bolts involved in the swap came off without much of a fuss, except one. The one was in a pump frame, visible above, so I could put it in a vice and work the bolt with CRC until it eventually came loose.

Visible here is the pressure side of a fuel pump. The nuts opposing each other are the power connectors. While changing the pumps you must pay attention which way the terminals are facing as the power leads are rather short. Out of four power leads involved in the swap, one broke, so I had to cut and install a new abico connector. The + and - terminals are sized differently (7mm and 8mm) so theoretically you can't install it wrong. The leads in the car are brown for earth and black (masked) for voltage. The terminals are covered with rubber hoods which, along with new abico connectors and nuts, come with the Bosch pumps. This is good because all of the old rubber hoods on my car had expired.

All the fuel line nuts and fasteners have copper washers which are not supplied with the pump so you would be well advised to buy some before taking on this task.

Since I had a lot of parts off the car, I decided to clean them up a little. This is something you get to do when you work on the car yourself... The piece of fuel line between the pumps had considerable surface rust on it but it's still solid and dry. The pump brackets were also badly corroded but still have life left in them and the basic shape was still in tact. All the parts had dirt and dust on them. The plastic casing had a thick rustproofing coat on it, so at least there was no rust... (tip: white spirit is excellent for removing rustproofing agent.)

Hose clamp cleaned - even that has the M-B logo!

Casing cleaned up.

New fuel pumps installed, wired and tested. Filter in the middle, pressure regulator in the background. In this picture you can see, just right of the right side fuel pump, the fuel pump for the Webasto heater. This is a factory installation so on Webasto-equipped cars, there are three fuel pumps inside the fuel block.

Casing sealed.

I took a test drive and sadly the acceleration misfire is still there. Bummer.

The work was not for nothing, of course. Having new fuel pumps can only be a plus. I've got a lot of life in my fuel block now, I got to empty the fuel tank completely which is good for reliability and I learned how to work on this part of the car. The new fuel pumps are much quieter than the old ones. I can probably sell the old fuel pumps, after I've tested them. At the end of the day, I got to work on the car, which is always nice.

Broke Another Mercedes, Part I

Life. It just keeps on giving. Today, true to its ways, it gave me lemons.

It's Friday. I'd left work, the sun was shining. I was going to get pizza. I turned into the parking lot of my favourite pizza joint.  Found an empty spot, drove past it, stopped to reverse in. I turned my head and started to reverse.

Suddenly, there was a muffled thud. It sounded as if I'd reversed into a pile of snow. But no, somewhere up front, a Volkswagen had crashed into me.

A grey-haired man, in his late 70s, had not seen me coming. This is understandable. He had also not heard me coming. This is less understandable. He had started reversing out of his parking space, and before he knew it, he was riding on my front bumper.

Not even a W126 will withstand the weight of a Passat pressing on its cold-weakened extremities. The driver side front wing was dinged and rashed, the bumper was scratched and torn off its brackets, the amber cornerlight broke, and the bumper chrome was dinged.

The grey-haired man evaluated the front of my car, and concluded the bumper had been scratched. After I had corrected his evaluation, he proceeded to claim it was impossible that the damage beyond the leading edge of my bumper was caused by the crash. I calmly explained to him that our opinions are irrelevant, and the police, who I shall invite over immediately, will judge the situation objectively. I inquired if the grey-haired man was in a hurry. As it turned out, he was, and asked me what sum of monetary compensation would free him and get him on his way. I gave him a lowball estimate of 1500€, which he claimed not to have. He told me, if he could see any evidence of the damage having occurred at the time of the accident, there would be no problem. Silently, I pointed at a shattered piece of amber corner light, laying on the ground two meters away from the grey-haired man.

The man, starting to realize the facts of the situation, agreed to stop bickering and wait for the boys in blue. As we were waiting for the Official Volkswagen Transporter, we started chatting. I told him about the SEC, and about the Club. He told me of the relatively low mileage of his Passat, and of the 1970s Yankee muscle in his garage. The mood began to lift.

Eventually, the police arrived. Data was entered into form fields. Zeroes were blown into a breathalyzer. Hands were shaken. The grey-haired man invited me over for coffee.

Naturally, the insurance of the grey-haired man will cover the repair of the SEC. This is bad news for the insurance company, which is the same one I have. They will no doubt remember my red W124, which they spent over 8000€ repairing. Hopefully, the parties involved will have noted my eye for detail, and will execute the repair to my satisfaction the first time round.

To be continued.

BE1319 - Becker Grand Prix 2000

Dear divine entity of automotive originality, forgive me for I have sinned. I have installed a non-period radio head unit in my car.

Granted, it's not the Japanese christmas tree you were probably expecting.

I was able to get a very reasonably priced Becker Grand Prix 2000 to replace the Mexico Diversity. This Grand Prix 2000 is a rare and pretty expensive model in that it has support for a Silverstone 10-CD changer. It also has all the same bells and whistles as the Mexico Diversity, and more: this one has RDS. I can now see channel names on the display.

The Becker 1319, or Grand Prix 2000 with CD capability, was introduced in 1991. It was sometimes installed in 1991 model-year C126 cars, but I believe it is very rarely seen in 126 chassis cars. Usually Mexico head units were used as those where the top of the line. The Grand Prix line was positioned below the Mexicos.

Thus the silver strip does not belong in the center console of my car. This is surely a peeve, but fortunately, there is grey everywhere in my car, so the silver strip at least somewhat fits. Looking at it in a positive way: installing this radio gives the interior a two-year facelift.

The radio is very nice compared to the Mexico. It has a way more sensitive tuner, meaning I get noticeably better radio reception. It also has way cleaner heads for the cassette, meaning cassette sound quality is excellent. Dare I say, cassettes in this GP2000 sound better than MP3s I played with the christmas tree I had in 2010.

More importantly, this radio will not overheat after an hour's listening. Even all the lights work, and the display is perfect!

There are drawbacks, of course. The reason this one was cheap (I paid 130 EUR whereas a perfect unit will cost up to 200 EUR) was that it has bad condensators. The radio takes a while to warm up and in the mean time, there is no radio reception at all. The cassette works, of course, so I can live with no radio until the car is warmed up.

There are other differences, too. The Mexico switched channels instantly. The Grand Prix takes a moment to tune in the new station (I assume this is because the Diversity has dual tuners but don't quote me on this). Also, the volume and tuning controls on the Grand Prix have a less chunky feel to them. Finally, the cassette mechanism is fully manual, whereas the Mexico did some of the work for you.

If I win the lottery, I might have the condensators replaced, and install a CD changer, another 150 EUR worth of audio equipment.


 

(The blog has now reached current events. Starting now, I'm blogging live.)