Black Smoke from exhaust???

altoids

Well-Known Member
Joined
Oct 24, 2007
Location
Archdale
Here are some specs about my vehicle before I get to the questions
.
’95 Jeep Wrangler with ’83 Chevrolet Suburban 350 4 bolt main estimate 200,000k miles.
670 Holley Truck Avenger w/.035 pump discharge nozzle & blue accelerator pump cam in the #2 hole.
Mallory 85 Series HEI distributor w/high performance coil
Accel 9000 high temp wires with DEI foil cover over boots & DEI 6” boot covers on top of that.
Accel shorty plugs gapped to .047
Hugger headers wrapped
K&N 14’ air filter
The reason I have all the protection for my wires is b/c my #5 cylinder kept burning my boot at the header. Had Taylor 8mm wires then put MSD Super Conductor 8.5mm (ones with extra thick boot) wires on they all ended up getting brittle at #5 cylinder. Just got the Accel’s last week trying them out hopefully they’ll work w/the added protection, if not it’s the Jacobs Electronics ceramic boot wires.
I changed my plugs & wires last week & I’ve noticed black smoke coming from the exhaust (I know it’s from being too rich, I can smell the gas). It seems to be bad only at idle. It smoked a little before I changed the plugs & wires, but not as much. I used the same type of plugs I had in it before. It idles between about 775-850RPM.
My question(s)
1. If I make the spark plug gap smaller will it help to burn more of the fuel?
2. If I lean out the idle adjustment screws should that cure the problem?
3. I plan on cleaning the air filter, will that help a little?
4. If I turn up the idle will that help at all (I think HEI’s can idle around 900-950RPM)?
Any other suggestions would be greatly appreciated. Thanks.
 
My suggestions-

yes, lean the idle screws, that's what they're there for.
put some regular delco plugs in it.
ditch the K&N and get a real air FILTER. (Purolator is my personal choice)
 
with a gasser...I always thought black smoke was oil, blueish was gas, and white was water...(I know black with a diesel can be fuel)...

this obviously isn't going to fix the problem...just want to make sure to correct my "mental encyclopedia" of troubleshooting...

Greg
 
Blue = oil, black = gas.
 
Oh yeah. :rolleyes: 14" typo error, it happens. I adjusted my idle screws & cleaned the filter, cleaned the carb up some. Fired it up, little puff of smoke came out. It had alittle hesitation at first but now it's running like it was before. Still smokes alittle (nothing like it was) but I expect some from an '83 engine with 200k + miles. I do have a small stumble when I shift from 2nd to 3rd mainly when the engine is cold. It's done this for awhile. Any ideas what might cause this?
 
I'm sure the timing chain being more worn out than a 45-year old hooker doesn't help keep everything in perfect alignment...
 
I'm sure the timing chain being more worn out than a 45-year old hooker doesn't help keep everything in perfect alignment...


...bad visal first thing in the AM.

The stock timing chains are crap after a while.....
 
Timing chain is only about 1 1/2 years old. Oil pump 2 years, water pump 1 1/2 years, fuel pump 2 years, starter 2 years. Can't figure out the stumble, it's not bad just annoying sometimes. I'll probably just let it be till I rebuid it after I put my Vortec stroker in. Thanks for the input. Side note: A 45 year old hooker should have master'd her kegel muscles long ago, no loosey loosey.
 
Have you tried bigger jets on the primary side of the carb to get rid of that stumble? Even though your idle is to rich that suburban needs lots of gas on that 2-3 shift.
Try 2 sizes bigger, you can always switch it back if it doesn't work. No comment on the hooker.
 
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