200D finally starts, but smokes alot
 

Hello forum,

I've got a 200D here that has sat for 12 years. Now it finally started to deliver fuel to the injectors, but when it finally starts, it quickly dies again, after a few revolutions.

I have video of it, and i would appreciate any help and ideas of what could be wrong.
Trying to start a Mercedes W115 200D after 12 years. Failed - YouTube

Thanks in advance, and greetings from germany,

Moe


Oh and I forgot to mention:
-Diesel pre and main filter are new,
-oil is new
-Clear diesel lines replaced, hence no visible air in the diesel system
-I freed the IP up with some rust easer, because it was stuck

What i haven't done yet:
-Adjusted the valves (they were all more or less in spec, so I will adjust them once I get/make the special wrenches). But i think if this would be the problem, it woudn't even start a little, right?
-Adjusted the injection timing. Does the same apply as with valve clearance above?

Are the glow plugs working? I would not have released the starter as soon as you did. I would have helped it run with the starter for a number of seconds to get it running well before disengaging the starter. It behaves exactly like a diesel trying to start at 25 degrees below zero which makes me suspect bad glowplugs. I'd also consider giving it a separate fuel supply in a gallon jug to rule out any fuel delivery problems from the tank.

Fuel delivery is fine, I have propably pumped over a liter of diesel with the handpump, no problem.

Hmmmm glowplugs... Is it normal for the coils between them to become hot?

Edit: right now the battery is charging, so later i will try to engage the starter a little bit longer, to see if that helps. Would be awesome if that made it run :D
Also thanks for your quick answer :)

Yes, if the squiggly wires between the plugs get hot, they are energized. I suppose it is possible for the wires to get hot and the plugs not work if the insulators were not in the right places, but that's not likely.
Engine was turning a little slow with the starter in my opinion but I thought the battery might be low.

Well then only time will tell. I will update this thread when I know more.

:D:D:D:D:D

IT'S ALIVE!!!!

Video to follow

1975 Mercedes /8 First start in 12 years! - YouTube

and here is a second video of the smoke that comes out of the exhaust:
Mercedes 200D Start - YouTube

Next thing I'll do is adjust the valves, but first I have to bend some wrenches... :)

It could be an issue with the Pneumatic Governor Diaphragm or a leak in the system.

Thanks for the tip. I'll check that tomorrow.

Another thing i remembered: the idle seems to go up-down-up-down, by about 100 rpm every 2 or so seconds

Mojoan-
Glad you got it started. Perhaps everything is fine at this point, but I heard one noise in your videos which I wanted to mention. It is a high pitched whoosh of air, that sounds like a dummer tapping on a snare drum (or maybe high hat). I got that noise on my car when I overtightened a glow plug, which broke it. This caused a leak of air to occur after each ignition in that cylinder. My car was able to start with this condition, but would not run well. So I might be imagining the noise in your videos, but I wanted to mention it.

Oh, and by the way, I challenge you to a drag race!

Thanks!

I accept the challenge but only if the amount of smoke you produce gives points too because you have an unfair advantage with those 10 extra horses ;)

Oh and i never touched the glowplugs, they are fine...

Just a thought: Could the diaphragm get dried out from 12 years of sitting?

This car does not have the rapid heat glow plugs that are used today. You have to hold the knob on the dash in the first position until the indicator glows red inside- this indicates the GP's are up to temperature. This could take as long as a minute.

There's a neat Bosch "quick glow" system that's available for these older models that works just GREAT!

Fluctuating idle RPM can be caused by sloppy throttle shaft at the intake butterfly, or sloppy shaft in the rear housing of the injection pump. Both need to have very minimal to no up and down play- some axial play is OK.

Replacing those with good tight ones makes all the difference in these old Diesels.

Black smoke is unburnt fuel. I'm betting your compression is low from sitting so long so you're getting incomplete combustion. I think after driving it a while the smoke might go away. Or, your air filter may be dirty.

After 12 years, all the soot in the exhaust system will come loose and blow out. That could be what you're seeing. If it continues, it's something else.

On the Compression issue He might have some sticking Piston Rings. Running the Engine may cure that but if not soaking the Piston/Cylinders in something like Marvel Mystery Oil might free them up.

Some People say using Synthetic Oil would also in time do the same.

Granted, it's not cold outside yet, but if you hooked up your block heater, you will nbe giving the cylinders a real advantage in case you have glow plug relay or glow plus heat issues.

Having a warm block makes life much easier.

Another day, another try.

I tried to start it in the morning, with a full battery and everything. Didn't work. Despite letting it glow for a while.

Ok, i thought to myself. Maybe it just needs some more cranking, just load up the battery and try again in 2 hours...

During those to hours my cousin called if she could come by to see the 200D run. "uuuhhmmm yeah. It doesnt run. But you can stop by and we can pull-start it."

1 hour later - 1pm my cousin arrives, and we hook the 200D up to the W124. After 200 meters of pulling it starts, ok let it settle in a bit before we stop and i drive it home by itself I think to myself.
That's when the engine starts to go TACKATACKATACKATACKATACKA-BUMM.




F**K.



I wildly honk at my cousin and gesture to stop, while forgetting to shut the engine down. Smoke pours out of the engine compartment. When we are at a standstill, i shut the engine down too.
A quick look into the engine compartment reviels the problem: Cylinder number two had blown out his glowplug :eek:...

Keep in mind, the engine kept running on 3 cylinders until i shut it off, no problem whatsoever. Well, apart from the huge cloud of smoke and the weird noise and... but im getting distracted here.

So i tell my cousin to drive to the next village where we can turn round.
Off we go, everythings fine, until on the last turn after which the road goes back to my home, we cut the corner too tightly, and the rope snaps :mad:

You're thinking now, that this might not be my day? Continue reading.


So now i get a ****storm from somebody who lives in the neighbourhood, of what in hell am I thinking, what if an accident had happened, and how do i plan to get that piece of ***** home? Calm down, i live 2 km down the road nothing will happen, we won't do it again. So he drives off, and we are right in business again, just reattach the cars, and then head home.

Just as we're about to do that, another man comes by foot with his family. He seems to be nice, at first he semms to smile at this whole mess I'm in. I greet him, and he asks me what we did there. So i tell him the story minus the part where the glowplug shot out of the engine block. He then asks me if I am aware of how illegal what I'm doing is. I tell him no, (Hell yes I am aware of it, i just didnt think it would go THAT wrong) He then proceeds to tell me why exactly it is illegal, and then he casually throws in there that he's A EFFING COP My brain goes all like :eek: WTF...

Luckily he let us go without any form of punishment, wich i'm very grateful for and i told him that.
But part of the "no punishment" deal was to not pull it back home like this, even if it was just 2 km.
So i call somebody I know who has access to a trailer and ask him if he can tow it back. Thankfully he agreed, (I'm also very grateful for that, since I only know him casually, mostly because he is into old benzes too :D)

So there we are. Car back in the driveway, bit more broken than before.
And i learned that a lot can go wrong, but if you're lucky about the people you encounter and know, it won't be so bad :)

Oh and here's a pic of the glowplug:
http://imageshack.us/a/img836/7708/glhkerze.jpg

So i sourced another glowplug, but i would appreciate input on what could have been wrong there, and if it maybe had anything to do with the rough black smoke?

Obviously the main problem was a faulty glowplug, but I don't want to take any risks ;)

What could have been Wrong? Re-read Post #10. Maybe that previous owner overtightend the Glow Plugs.

I had something similar once when I tried to remove an old glow plug from a friend's car me and my friend were working on. The top part with the loop remained in the engine, whilst the rest came out. My friend made a tool from a left-threader extractor: a ring was welded to it, so we could remove the remaining glow plug with a large fork. See the pictures below:

http://i185.photobucket.com/albums/x...waarland10.jpg

http://i185.photobucket.com/albums/x...waarland11.jpg

Now I realise we could have just started the engine (or rather, let the engine rotate on the starter engine).

These old glowers are prone to coming apart. Best to replace them all or upgrade to pencil type.

them big ole nuts, sure are easy to crank tight... someone must have reefed on it, and broken it loose in the center.

I LOVE the pencil plugs, but you've got to be GENTLE with the electrical nuts.

I really like them too, otherwise it would've probably been wise to just upgrade :)

Luckily the same guy who trailered me home has a lot of parts, and he gave me another glowplug, which, after some contact problems now works fine.

But working on an old benz is always a neverending story as many of you surely know ;)

Now it's the starter, but luckily the problem seems to only be worn down brushes, which I will buy and install tomorrow, so it will hopefully live to die another day :D

Govert:

I don't understand how your glowplug broke off in that spot in the first place o_O

What would have also worked for you and your friend is one of those teleskope magnets, wich are really useful if you drop a nut or washer into something. Especially if it's dropped into the engine. Don't ask me how I know.

ugh, you must be in Germany

How do you know? :P

This makes a good case for Reaming or otherwise cleaning out the Carbon from the Glow plug Holes.

It made a good case for not using Bosch loop glowers.

Also reaming out the glow plug hole still wouldn't help with an old glow plug which has been in there for years.

Magnets don't really worked, because the part of the glow plug was stuck into the engine. We removed the injector and tried to push the thing out, but that didn't work either.

I rebuilt the starter today, the most difficult part was soldering the brushes onto the old wires since i never soldered before, but it worked quite well.

Now the starter spins a lot faster, and it is possible to start the engine on one battery :D

Next problem to fix: Huge cloud of black smoke out back.

It most likely is the diaphragm in the injection pump since i have the most common symptom of diaphragm failure, that is oil in the vacuum line towards the intake.

Not an easy job, but what choice do i have /:

It is not impossible, but watch out for all the small parts inside the governor. If you can get hold of the axle bearings of the auxiliary mechanical governor, replace them too.

You need a dial measurement device to set the compensation path:

http://i185.photobucket.com/albums/x.../membraan2.jpg

http://i185.photobucket.com/albums/x...d/membraan.jpg

And here in reality, slightly improvised:

http://i185.photobucket.com/albums/x...d/DSC_0702.jpg

Read about replacing the membrane in the FSM/WIS and follow all the steps:

07.1 Diesel Injection System - OM616

there 07-215

Attaching the membrane to the control rod is the most complicated, certainly with the diesel pump still on the engine (and the engine in the car).

Thanks for the link, a lot of useful stuff in there :)


Oh and I forgot to mention something: glow plugs # 3 & 4 are bubbling when the engine runs... looks like they wanna be like their brother # 2 :rolleyes:

I'm probably gonna end up replacing them all anyways during the restauration.

Hi everybody,

for the last few weeks, i've been pretty occupied by school, but I managed to find out that bosch charges a whopping 350 % :eek: more for a diaphragm than the mercedes dealer! (60ish€ vs. 270€)

And in other news, I'm back to the point where it wont start again:(
It does fire after a lot of cranking, but it sounds miserable and dies again after a few secs.

Does anybody know from expierience if it can be enrichened so much by the diaphragm, that it just wont be able to run?

Greetings, moe :)

Maybe because of the torn diaphragm, the idle speed has been turned back by means of the screw of the air valve.

Did you change the diaphragm? What else was replaced/done? Does it glow normally? How long do you glow? Old glowers have to glow for about 30 seconds.

The diaphragm cannot “enrich”: the mixture of a diesel engine is always lean. If you have a pneumatic governor and there is an air leak (such as a torn diaphragm), it can happen that the air valve is closed, so it is difficult to suck in air, while the control rod of the IP is too far in the full-load direction, that will result in smoke, but the engine will run.

During starting you pull the lever of the IP in the start position, then the start quantity of fuel is injected, that is even more than the normal maximum amount of fuel.

Non running of the engine usually means not enough diesel injected.

great way to kill a good starter - too long a crank period, oh well - I like to attach a charger to my battery to assist in such situations. Have fun! Hooray!

Thanks for the info,

so if i understand that correctly what you're saying is that it's simply impossible for a diesel to die from too much fuel? Are you 100% sure?

(Also another thought that just occured: I filled the IP with oil, and I remember reading somewhere that it somehow gets rid of excess oil. Does it do that by injecting it? That would make too much fuel very possible.)

I'm just asking this question specifically, because I don't want to go about changing the diaphragm for a lot of money just to have a non-running engine afterwards and another problem to fix ;)



Well we seem to have a different definition of "good starter", here's what the brushes looked like vs. new ones:
http://img822.imageshack.us/img822/2161/img1883c.jpg
and the inside AFTER cleaning it with sand paper:
http://img259.imageshack.us/img259/1354/img1881x.jpg
:P

after replacing them it turned a lot faster. :D

Today I took out the IP vacuum regulator, cleaned it and visually inspected the diaphragm - not only did it look ok, but it also held vacuum quite well after I put it back together :)
(tested it with the thumb on vacuum connection method)

I also adjusted the gorilla knob a bit, I wasn't sure if it was too far in at the "running" position.

Sadly I couldn't try to start it afterwards, the battery's empty. But I was going to properly adjust the valves tomorrow, and replace the two other faulty glowplugs, maybe they somehow affect compression? Wouldn't surprise me with bubbles already forming at the seams :rolleyes:

Oh and FYI: the idle adjust screw still had factory paint on it - I don't think it has been turned.

If the glow plugs seal, they won't affect compression, even if they are broken.

As the diaphragm wasn't torn and the governor vacuum chamber holds vacuum, there was no need to adjust the idle.

The gorilla knob cable should pull on the lever when in the starting position and push on the lever when in the stop position. When at the drive or glow position, the lever should not be actuated. You can try pushing the accelerator pedal a bit during and after starting. Don't high rev the engine before there is oil pressure.

Diesels don't die from too much fuel, they may smoke or (if the governor doesn't work or in your case, start the engine without the air hose attached) overspeed, but they don't die. During starting the governor injects even more fuel than normally under full-load condition, just to help starting.

The IP has its own oil supply, that should be changed every time you change the engine oil.

Unscrew the level screw (it is hollow, so don't need to remove it entirely) and let diesel/oil leak out. Have some rags ready. The screw is at the red arrow in the picture below:

http://i185.photobucket.com/albums/x...ieselpomp1.jpg

Close-up:

http://i185.photobucket.com/albums/x...ieselpomp2.jpg

Unscrew the red filling cap (blue arrow), pour in engine oil until fresh engine oil comes from the level screw. That usually takes about 200 ml or 6–8 fluid oz.

Screw back the level screw and put back the red cap and you are done.

There is a vent tube at the back of the pump, if the level of oil/diesel rises too much, it will come out of this vent tube.

Any changes???

Sorry, I haven't updated this thread in a while, since I was busy with school :rolleyes:

Also it blew another glow plug wich was getting annoying, so I ordered four new ones, and today it finally STARTED UP again :)

I did however run it off a can of diesel purge, and it started much quicker on that than with the normal fuel line connected to the tank.
My thinking is that either the diesel pump is shot, or the fuel line is plugged/has a leak. Doesn't matter, since I plan on replacing ALL steel lines on the car eventually.


My biggest concern right now is the surging at idle speed, wich is quite hefty.

I'm going to measure the fuel consumption at idle again on the weekend, because it still smokes black like crazy, and I suspect that there is way too much fuel injected.


Edit: I forgot to mention, the smoke signals the diesel produced attracted a arab fella in an audi A6 who wanted to buy the 200D/My Mum's Opel Combo/My 230E, to all of wich I responded with no. :D

Edit2: I inspected the Diaphragm both visually and with the 'thumb on vacuum line connection method', and it seems to be ok :)

Did you hear the click when you removed your thumb? Even after some time? Try it after 15, 30, 45 and 60 seconds. Smoke and surging suggests a vacuum leak. Did you adjust the linkage according to specs?

Adjusting the linkage along with the valves (again) is next on my list, and I'm going to test the governor again at those time intervals according to your post.

Very good writeup by the way :)

I fired it up and moved it into the garage today, which was no problem even at 0° Celcius :)

I then tried adjusting the throttle linkage, but the german instructions I used weren't really suited. I did however manage to get it running sorta right by depressing the IP lever manually.
I'll try to adjust it according to the manual on Thatcher Mathias' site.

And I tested the vacuum in the IP regulator again today, this time while looking at the clock. It only holds vacuum for a dissapointing ~8 seconds.

If it's just a bad seal between the two housings, i will try to smear a little grease in there, and try again afterwards. If that doesnt help than a new diaphragma will be ordered.

But before any of that, there is a) the end of the world, or if a doesnt happen b) Christmas :)

So happy holidays to all of you :)

Often the air leakage isn't because of the diaphragm, but because of a worn-out axle of the poppet cam. That is on the back of the IP, connected to a lever and a rod. You can test this by dropping some oil on both sides of the axle, so you get a temporary seal. If the idle decreases (and/or steadies), than it is the axle.

Thanks for the tip - I think I know which axle you are talking about. Definetly worth a try.

Black smoke = too much fuel. White (pure white) smoke which disipates into thin air = steam. Whitish (bluish) smoke that wafts away in the wind or hangs around = unburned fuel/oil burning.

Black smoke without the engine exceeding idle, and assuming good compression/mechanicals, is most likely a bad injector or something at the IP such as a stuck delivery valve.

The cylinder responsible "may" be able to be isolated by cracking individual lines at each injector, in turn, and listening to the engine and watching the exhaust.

Black smoke could also be caused by air getting into the pump and the air can delay injection because of contraction, then diesel (explode) inside the injection line and blow excess fuel into the cylinder late, and cause all kinds of weird running problems. That it ran better on the purge may in fact point to that issue.

I tried dropping some oil on there, and it held vacuum for about 30 sec. and maybe more, but I couldn't test it for a longer timespan because my finger was freezing off. :P

Is there any way to get a proper seal at the axle?

There are two methods:

1. Replace the entire back cover with a new one (use a new gasket). MB used to sell these back covers, but I think they are no longer available. You could try at the dealer. (Bosch) diesel workshops sometimes sell them.

2. Replace the bearings and O rings of the axle. The problem is to find a good (Bosch) diesel workshop who sells these parts.

So yes, but finding the part(s) can be difficult.

Maybe a metal workshop can make the bearings for you. Rubber O rings can be universal.

Two things:

The SKF company has the largest selection of bearings in the world and they may have a reference for yours.

O-rings are avalable here in the US from a source which sources MB, Chrysler, Ford and GM in a city near Detroit.

I buy many unusual O-rings there for Citroens, so it is easy to mail O-rings if you need them.

Plus, if you need such helkp, I speak, read, write German and I can look to see if I have the Reparatur handbuch for the 200D in German if you need this.

But ebay.de has these also for not so expensive a price.

Viel Gluck!

Thanks for your tips :)

I have no real progress to speak of here, more of a leap backwards :mad:

The starter refused to work again, and then the my DD started to act up with vacuum problems and took away the time I wanted to spend on the 200D. Also I got more lazy as the temperature continued to fall :D

I have a question regarding the starter wiring: How do I jump the starter directly from the battery?

Do I just connect the positive battery pole with the small wire (golden philips screw in the picture below) and off it goes? Or would that short the circuit?
http://img843.imageshack.us/img843/9687/img2110f.jpg

If that doesn't do it, then it is likely that the copper wires I soldered together sperated again...

The starter turned out to be toast, the brushes had already disintegrated completely, probably due to some short in the starter itself. So i went out and got a good used one, which has a busted gear wheel... So it will turn the engine for 15 sec. and then go free spinning :mad:

And the W124 is acting up with the TÜV inspection due this month, so that's not helping with this project. :P