Black smoke at idle. . .when warm

[jaynes]

Now I've posted on this subject a dozen times already, and I haven't posted in a while. My truck is still puffing black smoke while idling in gear at a stoplight or something. But I also noticed the other that it puffs a very thin cloud of black smoke in park or neutral even! Could this be due to a clogged air filter? Not getting enough air or something? I just relized that the air filter probably hasn't been changed since I bought it two years ago. Could this pose a problem? #ad
#ad
I hope I haven't done damage to my baby. I haven't checked the injectors. I've only seen it done, I've never done it myself. Cracking them, i mean.

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'91 D-250, Cummins, 3 speed auto, 165k, Hurculiner bedliner, after market bumper,custom one tone metallic blue paint job (sorry no pics) and completely stock... . for now anyway

 

[BushWakr - RIP]

Jaynes,

I'll take a shot here. How's your idle speed, is it rough/smooth, general engine smoothness?? If you haven't changed the air filter in 2 years you really should do so straight away. If its plugged it will mean that you are running much richer than you should. Also if its done this since you got it you may need to adjust the AFC counterclockwise a bit, as well as starwheel I would think (JUMP IN HERE PIERS!)
Do you use any additive for your fuel? You may want to clean out the injectors. If they get a bit clogged they will end up spraying a "coarse" fuel cloud and it won't burn properly/fully. That will mean black soot out the tailpipe. Whats it like under WOT conditions??
Just my . 02cents.

 

[jaynes]

Well, the engine runs great. Idle is really smooth. But, in gear, especially when hot, it idles really slowly. I've heard other CTD's that idle alot faster than mine when in gear stopped. The engine also runs really hot in the summer. The gauge gets to the middle point and sometimes further in the summer. It then starts to idle erratically. I don't know how to adjust the AFC wheel or the star wheel. I don't even know what AFC stands for. I don't know what WOT stands for either. I'm going to change the air filter, but I don't know how to check or clean the injectors. I need some education guys, and so far you've all been a big help. Can you teach me some stuff here so I can fix my idle smoke problem? Thanks!

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'91 D-250, Cummins, 3 speed auto, 165k, Hurculiner bedliner, after market bumper,custom one tone metallic blue paint job (sorry no pics) and completely stock... . for now anyway

 

[BushWakr - RIP]

Ok Jaynes,
I'll do my best here. First I'd recommend you look at the picture on the website below... http://www.tstproducts.com/pump_adjustment.html
Then start by reading the topic called Super Hot Pre 93, the address for this is ... . https://www.turbodieselregister.com/ubb//Forum13/HTML/000084.html
Its right here on this web site, just search the 1st Gen. forums for pump adjusting, or VE-44 pumps etc. This will get you started on the basics of what things look like, what they do, and how to adjust them.
I'm like to try and email you a color picture of the injector pump on your truck. Let me know your email address so I can send it ok?
Just click on the little icon second from left above my post to email me.
A couple of the best sources for this around here is Piers Harry or Old School so they may also help you out. In the mean time I'll do my best to get you rolling. I'm off to work so I'll check in again tomorrow and see what else we can do. BTW, Wot = Wide Open Throttle, the AFC will adjust smoke particularily from idle to the first 30 feet of "launch" or so as I like to describe it.
The Star Wheel adjusts fueling before any significant boost comes on.
Regards, Bush'

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93. 5 W250 4X4,HD Spring Pkg, Rancho 7000's, Rear Swaybar,Dual Shock Front Stabilizer,BD 180HP Injectors,31/2" Mandrel bent exhaust,BD16cm 'Hot End',Modest Pump Tweaks(lock collar still on)Star Wheel@3oclock/Timed @ 1. 37mm,K&N Air,Isspro Pyro (Post Turbo),Tach,transmission Temp,Auto Meter Oil Filled Boost Ga. , 3:54's, 4 Speed Auto, Clubcab, Aftermarket Reclining Buckets w/ctr Drop Down seat/console, Black over Silver, 22psi,285-65R-16's,American Racing Clear Coat Mags, Amsoil 15W-40HD Marine,12,000 lb. Warn Winch,KC Spots. 103,900 Kms (64,600 mi's). NOT A VENDOR,Just an end user

[This message has been edited by BushWakr (edited 05-09-2001). ]

[This message has been edited by BushWakr (edited 05-09-2001). ]

 

[Lil' Dog]

If you could somehow check the idle speed, I think Bush is on the right track. The high engine temps at idle are a syptom of low idle speed as the water pump turns too slowly to circulate the coolant properly. Before the air/Fuel controls are adjusted the idle speed should be investigated. Setting the speed to above 750 is recommended. I run mine around 800 for smooth idle and higher oil pressure.

J-eh

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Jason Hoffman
Lil' Mack - 89 D250LE 5 Spd 3. 54 LSD Reg Cab. K&N,"tweaked pump", BD Injectors, Banks Pyro/Boost, 3. 5" Exst tail section straight. E&M Custom seats. Bosch H4, PIAA 80W/80W HdLites. 100W Drv,55W Fogs.
237,500 miles (380,000 Kms) 7850 Hrs. Cummins Power Booster member.
The Original Turbo Diesel

Lil' Mack Pics/March 2001

 

[Scott Elliott]

Thank you Bushwakr for those links... now for a stupid question. When adjusting the smoke or idle speed, can this be done with the engine running or does it have to be off?

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1993 silver and black D250 club cab,le, long bed, 2wd, automatic,3. 54 anti-spin, 95000 miles, stock truck except for the K&N air filter, and US Gear Gauges (tach, pyro, trans temp, turbo boost)

 

[BushWakr - RIP]

You can adjust both with the engine running but the idle adjust. will be a bit tricky. I found the lock nut wants to "run" away along the adjust. screw, plus it can be frustrating to keep the screwdriver in the slot. Then you have to try and get a socket on it while its rattling around. Some guys use a little punch and tap the nut one way to tighten and the other to loosen. I prefer a 1/4"drive deep socket (10mm I think) and 1 1/4" extension on the end to do this part.
The smoke adjust should be no problem, in fact thats how I've done mine on a couple occasions.

[This message has been edited by BushWakr (edited 05-11-2001). ]

 

[Power Wagon]

No pump adjustment will have any effect on air/fuel conditions at no-load idle.

Your mention that it idles slow is a good clue... It's idling too slow. Speed it up to about 750 to 800 in neutral, and all the smoke and heating should go away.


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ICQ 3807791 Power Wagon
www.my2kcity.com/powerwagon
Mark Koskenmaki, General Diesel Moderator