Getting Black Smoke like a MAC truck from my 300d - PeachParts Mercedes-Benz Forum

777funk · #1 06-29-2009, 09:28 PM

My 603 is smoking like a mac truck currently. I have been trying to figure out why. I removed the ALDA a while back which of course smoked when I gave the pedal some metal. But I've since put it back on and I'm still getting lots of smoke.

I'll jump right to my question. I revved the engine in park to around 3k or so from idle and I notice no movement of the wastegate actuator rod. I'm assuming I should see it move. Is that right?

A little history on the car. The MB dealer replaced the turbo and exhaust a year ago for free with the Trap Oxidizer recall work. This was one year ago on July 5th. I noticed that there is oil all over the outside of the turbo housing (I'm guessing it's slowly coming from the oil feed line). So... that means that someone's seal job work wasn't the greatest. I am also noticing that the car has blue smoke after it's warmed up. Maybe the turbo is shot??? Could this be? It still goes pretty good and I can hear it whistling (I think anyways) as I drive up hills and put my foot into it.

I'm taking it to the dealer who did the trap ox job on Wednesday but I want to have an idea of what I'm talking about before I head in to there.

thanks,
Nick

kerry · #2 06-29-2009, 09:49 PM

Change your air filter?

777funk · #3 06-29-2009, 10:27 PM

Quote:

Originally Posted by kerry

Change your air filter?

The air filter is nearly brand new (well less than 3-4k on it).

777funk · #4 06-29-2009, 11:37 PM

any clue on the wastegate? Should the wastegate actuator be moving if I rev it to 3k in park?

rcounts · #5 06-30-2009, 12:29 AM

I kind of doubt that the turbo is going to build enough pressure to even start to open the waste gate with no load on the engine. I know a lot of turbos won't build significant pressure unless the engine is actually under load. Even 3000 RPMs in park probably isn't going to build up the 6 or 8 PSI it takes to make the actuator move and open up the wastegate.

I may be wrong, and if I am I'm sure someone else will chime in to correct me.

compress ignite · #6 06-30-2009, 01:20 AM

'Turbo still thinks your @ Idle,need to put it in gear and drive (Load) to have
Turbocharger pressurize the intake.
Black smoke is typically over-fueling.(That's why you got question about AF)
BUT,If something is dumping enough oil into the intake (Turbo seals gone) it might look "Black".
Motor Oil is FUEL to these engines,once they're Operating!

So ,if you've got your normal Diesel Fuel from the Injection System AND
Motor Oil from somewhere else (In the Intake system) ,You're Over-Fueling.

What's your oil consumption like?

LUVMBDiesels · #7 06-30-2009, 06:57 AM

^^^ Exactly.

Also how is your driving style. If you loaf along a lot staying off the turbo, you can build up carbon and soot in the exhaust which then gets blown out when you hit the accelerator. I notice that in my 603. If I am doing a lot of city driving and don't get into boost that much, when I take it on the highway it smokes a lot more than if I am doing lots of highway driving. Take her out for an "Italian Tuneup" and see what happens. It is fun too!

777funk · #8 06-30-2009, 08:15 AM

Well oil on the outside of the turbo is probably not a good sign. I'm guessing that means the inside is not getting as much as it should from the oil feed line. I hope the Dealer will stand behind their work.

tbomachines · #9 06-30-2009, 08:28 AM

Quote:

Originally Posted by rcounts

I kind of doubt that the turbo is going to build enough pressure to even start to open the waste gate with no load on the engine. I know a lot of turbos won't build significant pressure unless the engine is actually under load. Even 3000 RPMs in park probably isn't going to build up the 6 or 8 PSI it takes to make the actuator move and open up the wastegate.

I may be wrong, and if I am I'm sure someone else will chime in to correct me.

To my knowledge you're absolutely correct. That's why turbo cars have to really rev it at the line in order to build up some sort of boost at start of a drag race - and even then there is significant lag...Unless they've gone VGT?

Even our cars won't kick in the boost until well into the powerband.

MTUpower · #10 06-30-2009, 08:30 AM

Always help to post the chassis as well as the engine type. How much smoke before the turbo/exhaust change? Before the alda removal? How long has this been going on? Build up slowly or suddenly? No load=no boost=no WA movement.

777funk · #11 06-30-2009, 08:58 AM

Quote:

Originally Posted by MTUpower

Always help to post the chassis as well as the engine type. How much smoke before the turbo/exhaust change? Before the alda removal? How long has this been going on? Build up slowly or suddenly? No load=no boost=no WA movement.

Right now I only have one MB (in my sig line). It's an 87 300d with a 603 turbo 6 Zyl (sp

) engine.

As far as smoke before the dealer update, there was none. Same goes for immediately after. When I removed the ALDA (shortly after the update) it smoked pretty good but only when I floored it. I put the ALDA back on about 6 months after the turbo change and the smoke mostly disappeared but didn't go away which I thought was strange. Lately I'm getting smoke even under light to moderate acceleration and blue smoke at idle. That's when I looked at the banjo oil feed line on the turbo and it's got oil caked all over that area.

777funk · #12 07-03-2009, 09:08 PM

Well,
I got a call from the dealer who said that he tested the turbo and got a little over 9/10ths of a bar which is in spec. So unless he's lying, I'm guessing it's a fuel issue.

On a side note... I just got charged $55 for him to take one measurement. I need to by the fitting for the intake manifold to connect it to my 1/4" Male Pipe thread gauge. Anyone know what size I need for the intake manifold boost pressure on a 603?

Back to the smoke... the car has Bosio injectors. I suppose this could be the issue too. Times like these I wish I had a pop tester!