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1984 300TD
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Discussion Starter #1
Hey Folks
Here is the puzzle I'm working on. its 1984 300TD now with manual 4 spd
the CD repair manual I have produces many heavily pixilated images so Im daunted by guessing at things due to zero clarity for some images, conflict with modern Mac computer with older CD set

Its smoking too much at times so I need to troubleshoot EGR and other systems that may be my issure here

does anyone know where to find repair file 14-100 with crystal clear illustrations or the whole set for that matter that will open clearly on a mac, I need to review trouble shoot EGR and all vacuum connections. If you have it digital and can send it that would be wonderfull
This is 1984 300TD Federal

Already did these things and see good improvement already:
new monarch nozzles with pop test / balance
renew air and fuel filters
engine compression ie ring wear should not be it, less than 100K on rebuild engine, its got good compression
IP timing set at 27 degrees

Now ready to verify turbo boost I'm getting, that could contribute to exhaust smoke

I need to trouble shoot operation of EGR, yesterday cleared near total obstruction by black crap build up in it,

next I'll verify fuel supply connections are snug, not taking in air bubbles.

thanks very much in advance
 

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There is not one person here that will suggest the EGR remain functional. There is literally no benefit to its operation.
 

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1982 300CD
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5,134 Posts
To make sure the connection is closed, you could replace the gasket with a thin piece of metal plate (think soda can), or you could could get a block off kit that allows you to remove the EGR completely, or you could even swap your manifolds with a pre-EGR 617A for the cleanest look possible.
 

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1985 300 TD 1981 300 SD
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348 Posts
I even made my own, the intake block off plate was easy, on the other hand the exhaust manifold port I did my own way by bronzing around the inside of the port then cutting in threads for a pipe plug. Now I did have the manifolds off of the car for cleaning while I was rebuilding the turbo and decided to do the egr block off while I was there.
 

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1984 300TD
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Discussion Starter #7 (Edited)
Thank you for the comments. I'm workin' on those things
In the meantime "pulling the plug" of vacuum feed to EGR and air diverter and capping those vacuum lines off, new monarch nozzles with pop pressure balence a new K&N air filter has made very good progress.
Adding boost controller has been enlightening but is disappointing since it makes little or no difference unless my foot is all the way into the accelerator which it never is during daily driving. Never has been even once until checking the result of adding the boost control.

The FSM plot of turbo performance shows the boost should be: "full load" (pedal to the metal) boost ramp up as strait line from +/- zero boost at 1000 RPM to max boost at 2000 RPM. ON this engine full load ramp up pops above zero just under 2000 RPM and reaches max at around 3500. Irrelevent for daily driving. I'm seeking an answer wtf is with this descrepancy?

Next : ALDA adjust and seeking answer to why the boost ram up seems to be to some extent a function of accelerator pedal motion not just increase in RPM meaning jumping on the accelerator cranks the boost psi up all by itself before the engine RPM has a chance to increase. Seems to .
 

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Get rid of the K&N. It gives ZERO additional power, air is not the limit to power on your engine. The factory paper filter can flow much more than the engine can use while being many times more efficient at filtering out dust than the purple screen door you put in.

Check your throttle linkage that the lever on the pump contacts the stop screw when the pedal is pushed to the floor. The rubber bushing on the firewall can tear and look fine at rest.

The ALDA is the last thing you should touch AFTER checking all other sources for correct operation. Fuel filters, throttle linkage, valve adjustment, turbo bearing play, exhaust restriction (disconnect exhaust pipe to check for internally collapsed muffler/resonator), you've already checked the air filter.

The other thing is you've got a manual. You don't have a torque converter to allow the engine to slip and load up, you can lug the engine down lower RPM than it was designed to run.

Attached is the boost and power curve of a properly tuned 300D on a chassis dyno.
 

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1984 300TD
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Discussion Starter #9 (Edited)
can I ask what are STTP and STPT? HP and torque?
thx
that blue green line describes the boost I seem to be getting very well

Throttle linkage: I assume its possible some of the fuel may not reach the injectors if the linkage travel isn't normal.
Thinking about it: in the "pedal to the metal" setting suddenly max fuel and thus hot expanding combustion products hit the turbine and it responds quickly with rapidly increased boost. The boost pressure gauge is analagous to a turbine speedometer.
 

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Standard Temperature and Pressure.
In a way. RPM increases with flow, but there is far greater increase with pressure ratio.
 
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