Smoke. Clouds and clouds of smoke. 1984 300sd - Page 4 - PeachParts Mercedes-Benz Forum

angst · #46 05-24-2012, 11:48 PM

if by oil in the inlet pipe you mean the pipe between the air filter and the turbo yeah it has always been kind of oily for years and was on my previous 300sd to. I thought it just does that from the valve cover vapor capture thing in there.

So, turbo related leaking is a strong contender.
I would feel a lot more comfortable fiddling with that if I can get to a point where I can call this timing part handled and put the valve cover back on.
Any of you heavy hitters have any ideas about my screwball timing readings?

I've got plenty of time to work on it this weekend but there is a holiday in the states here on Monday so Tuesday would be the soonest any parts ordered Friday would be here. Thinking of ordering at least the injector heat shield washer things so I can do a compression test and at least soak the injectors in something. I did get a slight improvement when I did diesel purge a few months back.

Nailing noise I had this winter is gone though but the smoke has gotten progressively worse over time.
Starts quite easy though even in cold weather down to sub 30f which seems to suggest compression is at least reasonable.

Wagnerwerks · #47 05-25-2012, 12:14 AM

Yup. 1/8th inch play is a crapload and has almost certainly knocked out the seals. I have a small shop and specialize in German cars, mostly tdi vws. Turbo seals go bad around 200k or so. Not an uncommon thing. You can rebuild it with a kit, or get one used.

angst · #48 05-25-2012, 12:16 PM

video of turbo play. There is slop left to right and up and down but none forward and back.
Video of grabbing shaft with piers and wiggling.
Watching the video myself it looks like a lot more slop than I realized before. Is this in the normal, marginal, or way out of tolerance range?
Edit update: spin with fingers test video

Still curious what is going on with my strange timing readings. We have all been kind of stuck on this issue for pages.

funola · #49 05-25-2012, 12:37 PM

From what you posted earlier:

"It is not really hard to start after an overnight sit. After it is warm it is just as easy starting as any gasser with no glow plug time needed."

I gathered that your timing can't be that far off. Single tank WVO blending take it's toll slowly. The extent and how fast it happens is variable depending on various factors. Some get away with it longer than others.

Quote:

Originally Posted by angst

Army
Yep its a turbo. I didn't realize 300sd came in any other flavor.
Brian C did weigh in early in the thread with thoughts that it is either oil or coolant before I got sidetracked on this timing measurement thing that has that I have kind of stalled out on.
From your link regarding cam numbers that one guy replied to you.

Wagnerwerks
by check the downpipe I reckin you mean unbolt the exhaust and look for oil in the first section coming off the turbo?
Ill take another look at the play in the intake side of the turbo and see if I can better quantify how much play is in it.

Funola
interestingly enough the smoke started in November at the same time I stopped blending in alt fuel for the year (I run 100% dino D in the cold months). I had initially thought that I was suffering from bad fuel at the pump.
There is a little crack at the top of the mating surface of the goldenrod spin on filter. I don't know if is sucking air and if that could cause smoke like this but Ill post a pic of that up in case it is relevant.

Stretch · #50 05-25-2012, 01:50 PM

Quote:

Originally Posted by angst

...
Still curious what is going on with my strange timing readings. We have all been kind of stuck on this issue for pages.

That's all I'm worried about.

Did a previous owner set it that way to burn stuff other than diesel?

7 degrees ATDC ain't right!

Stretch · #51 05-25-2012, 01:53 PM

My thanks go out to everyone else who are helping out with this thread - I was running out of steam!

angst · #52 06-08-2012, 05:25 PM

Here is the latest. I adjusted the valves again and put the valve cover back on just to get the satisfaction of it not being a dead carcass in the driveway. (still runs with significant smoke).

I pulled the injectors and took them to a diesel place to get them tested.
The verdict from that is: Opening pressure is kind of low but within tolerance. Spray pattern is terrible. One is stuck open. They pulled one of the injectors apart to get the nozzle number and noted the fuel had a sticky substance in it. (that was not unexpected of course)

Could we have our culprit? A stuck open injector sure seems like the sort of thing that could cause smoke.

They recommended having them rebuild all nozzles for $360us and said I would only get a few days worth of success by cleaning and not replacing the nozzles.
I wanted to try cleaning them myself since I don't have much to loose by trying so I politely back-peddled out of there to take them home and take apart myself and clean them this weekend.
I'm excited that I may be able to actually sink my teeth into a tangible target at this point.
What do y'all think?

bd1308 · #53 06-08-2012, 07:00 PM

I'd look on diesel giant on his howto for nozzle replacement. And please PLEASE run less of WVO. I bought my car last year, and the PO ran veggie oil in his car. I was wondering about WVO when I first bought my car, but now I wont ever run it. It's just too much to risk saving a few bucks when a new engine + IP costs like 9Gs. It ran like absolute crap for the first six months, but everytime I went through a tank of diesel it ran a little bit better. It just now got to the point where I consider the engine to be running "good". I had bad grey smoke too when I first got it.

funola · #54 06-09-2012, 10:50 AM

You have nothing to lose by cleaning the injectors, however, you have to get them pop tested afterwards to be sure you have not made it worse.

Find a different shop maybe?

Stuck open= bad atomization = unburned fuel which could explain the smoke. Some of that sticky substance from bad atomization invariably gets into the piston ring lands and eventually coke them up. They will be much more difficult to diagnose and clean than gunked up injectors.

Quote:

Originally Posted by angst

Here is the latest. I adjusted the valves again and put the valve cover back on just to get the satisfaction of it not being a dead carcass in the driveway. (still runs with significant smoke).

I pulled the injectors and took them to a diesel place to get them tested.
The verdict from that is: Opening pressure is kind of low but within tolerance. Spray pattern is terrible. One is stuck open. They pulled one of the injectors apart to get the nozzle number and noted the fuel had a sticky substance in it. (that was not unexpected of course)

Could we have our culprit? A stuck open injector sure seems like the sort of thing that could cause smoke.

They recommended having them rebuild all nozzles for $360us and said I would only get a few days worth of success by cleaning and not replacing the nozzles.
I wanted to try cleaning them myself since I don't have much to loose by trying so I politely back-peddled out of there to take them home and take apart myself and clean them this weekend.
I'm excited that I may be able to actually sink my teeth into a tangible target at this point.
What do y'all think?

angst · #55 06-09-2012, 03:24 PM

Is the needle supposed to just come right out of the nozzle? All the tutorials are a little vague regarding handling the needle and nozzle.

I took the known problem one apart and tugging with the shaft of needle that is on the inside with pliers it doesn't come out. I disassembled a second injector and it does the same.

I am afraid to put any more tugging pressure till I know what I am dealing with here or if it is ok to grab that.

After reading around a bit it sounds like taking the needle out of the nozzle is bad to do anyway.

So, what should I do here?

funola · #56 06-09-2012, 04:40 PM

The needle should float freely. It acts as a plug against the opening in the npzzle face. Fuel pressure lifts it by opposing spring pressure against the needle and fuel is injected. Sruck open needle = streamers - not good.

Try soaking it in carburettor cleaner and work it loose little by little.

Did you ever sort out where your timing is set?

angst · #57 06-09-2012, 05:20 PM

Ive taken all 5 apart now and they are all the same. I can not get the needle removed from the nozzle even when grabbing the shaft bit and pulling with pliers.
Ive went and bought an ultrasonic cleaner but it doesn't seem to be doing much. Ive tried brake cleaner, carb cleaner, naptha, paint thinner, and simple green citrus cleaner.
After 7 hours wresting these today not a single needle will budge.

I have each set up in a different solvent to sit overnight but hopes are not high. It is looking like this weekend will be a fail and I will have to order parts on monday and this darn beastly project will have to continue to linger.
If I get all new nozzles will I be able to just assemble em up, or am I still going to have to shill out big bucks to a local diesel place to balance them to each other? Remember the place I had em tested ($45) wanted $360 to put new nozzles in the already removed injectors and Im not sure that even included balancing.

I've been reading threads about Monarch nozzles and they sound like the bees knees but there is apparently only one place you can get them and guess which ones they are sold out of as of just a couple months ago..

Should I abandon thoughts of getting a hold of a set of these?

Regarding timing: No, I never did sort out what was going on with the timing so I just moved on to trying other things. I did a bunch of scrubbing the other day around the injector pump and found a chisel mark and can see that the pump is rotated in toward the engine slightly from where the chisel line was made.
Don't know if that is relevant or not.

Update: I powered through for a few more hours till almost and midnight managed to get 4 of the needles out using a method of holding the shaft part in a vice grip and wedging against it with screwdrivers and needle nose pliers. I hope I didn't mar up the mating surface of the nozzle. Ill be able to see in the morning if the garage doesn't burn down overnight with all the fumes in there.

angst · #58 06-10-2012, 11:39 AM

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAGH.
(for brevity imagine 50 curse words here )
(and some more screaming here for good measure)

So close but so far. On the home stretch and the final pin snapped.

Update next day (monday):
Hit the phones and the interwebz wrangling up the part. My ace in the hole local foreign parts place had the nozzles in stock so I picked one up ($42). Whole thing was dipped in wax or something to seal it. Wild.
I methodically prepped all the injectors tonight with additional thorough cleaning and ultra light lapping. The tech at the shop were I got the pop test discouraged lapping altogether as being too high of a risk of making a seal worse. I just did only the weight of the parts in circles on 2000 grit lubricated with diesel.
Tomorrow its off to get a torque wrench to tighten em up and put em in.

angst · #59 06-12-2012, 05:28 PM

While pulling the heat shelds out I discovered that the hole for the #2 injector is 100% occluded with carbon.
I assume this means that injector was not firing or was hardly firing.
I chipped away at that and blew it out with air.

The cleaned up injectors are installed and I did a test drive.
Verdict: Smoke is 90% gone. I can actually sit at a traffic light without enveloping the people around me with smoke. Some billowing at startup and for the first 7 minutes or so of driving but the smoke really drops to almost nothing.
I think the injectors, or specifically the #2 injector was the culprit.

WHOOOO HOOOOO

Stretch · #60 06-13-2012, 03:35 AM

Congratulations - well done.

I still can't understand what was happening with the timing check though...

...anyway for this one I'm happy to say "if it ain't broke don't fix it" - I hope you are too!