Black Smoke - help

[sprange67]

Hi All,

Newbi and first post one here.

First I dont have a 309 but a camper (sorry   ) with as XUD9TE engine and this place seem where a lot of you guys know your stuff.

Basically I have black smoke, I know this means either too little air or too much fuel but I'm totally at a loss, see below:

So what I do know and have done

• Engine just fully serviced (low mileage 45K)
  
• All filters changed
  
• Valve clearances adjusted and in spec
  
• New cambelt (plus water pump and tensioners) and timing correct (double checked)
  
• A fully reconditioned Bosch Injection pump (by Diesel Bob) timing checked with dial gauge and spot on
  
• 4 reconditioned injectors from Diesel Bob (with new washers and heat shields).
  
• Plenty of turbo boost – checked with boost gauge – up to 18psi when giving it the full monty
  
• Does not touch any oil whatsoever, goes very well and does not heavily breath (through the dip stick) – So I have assumed the compression is fine, additionally the mileage is low, so I’m not looking at a compression test at the moment.
  
• 4 new heater plugs (I know that will have no issues with black smoke)
  
• New fuel pipe clips on all the fuel lines
  
• All new injector leak off pipes
  
• Clean gauss on fuel pickup pipe
  
• Induction air pipes all good, clips tight, no collapsing going on, which is reflected by boost
  

 
Issue
Unless the throttle is very lightly pressed it black smokes, which at night is excessive. Basically it will put down a blanket of smoke if booted.  I disconnected the boost pipe, but when revved (stationary), it will black smoke.  Because of this, I’ve assumed that its not the boost mechanism causing the smoke.  Also when flat out, full boost - no smoke
 
Makes no difference with the EGR enabled or disabled. The EGR valve has been replaced and is fully works (I have also tried blanking as a belts and braces approach).
 
I have disconnected the cold start advance solenoid, which helped.  So I assumed I got the timing wrong.  So have made incremental adjustments to the pumps retard/advance position. The best result was someone’s online suggestion to use a 6.5mm drill bit to set a starting point, maybe I moved to pump too far in my incremental steps?


My last thought is there is potentially a slightly clogged intercooler as the boost measurements are pre intercooler, but would have thought not

Any thoughts or suggestions (scrapping is not an option) dont care what it is, as I'm at the point of trying anything

Thanks in advance
Steve

[ekjdm14]

Restricted on the exhaust side, internally collapsed silencer maybe? Quick test run with the downpipe disconnected would show it up.

Apart from that, what did your pump guy have to say as regards the LDA pin, preload, stop and general pump settings? If the LDA stop is wound too far in, or the spring preload too low that'd cause excessive smoke off boost/on light boost. If the pump has anything in the way of non-factory tuning (steeply ground LDA pin etc/gov mod) that'll affect things too.

If the exhaust doesn't yield anything, I'd probably read up on how the LDA works so you're more familiar with what settings affect what part of the fueling & turn the pin to a less aggressive slope if it's not already on the "tame" side, then experiment with winding the stop out a few turns (best shot IMO as you mention smoke with LDA disconnected) or increasing the preload