Black smoke under load

[gamber]

I just posted some information on smoke color, now I need some assistance in troubleshooting my IDI
First the link: http://www.vwdiesel.net/phpBB/viewtopic.php?t=10578

My high KM IDI (1400 km per week!) has recently started to smoke under load.  The color is black, so I am assuming it is getting too much fuel.  Any ideas where to start here?
   - increase the boost?
   - decrease the max fuel screw?
   - decrease the enrichment?
   - is it an air leak?

Thanks!

[Black Smokin' Diesel]

First check the air filter to see if it's clean. Then I'd check the boost pressure to make sure it's ok. The diverter valve may be broken and dumping all the pressure out (try to block it to see if it helps).

[rob76]

Every older diesel I see on the road makes black smoke under acceleration. Ever dump truck and school bus too. Unless it's pumping out huge clouds of it I wouldn't worry too much.  But then again I'm no expert.

[Op-Ivy]

First check the air filter to see if it's clean. Then I'd check the boost pressure to make sure it's ok. The diverter valve may be broken and dumping all the pressure out (try to block it to see if it helps).

I second the air filter idea.

Also, do you run any additives? Plugged up or worn injectors can cause unburnt fuel.




Matt