this gets worse and worse . . .

[trousertrout666]

frequent viewers of this forum will recognize my sn, and my problems. I know about what white smoke and blueish smoke mean, and I know black smoke isn't good at all, but what does black smoke out of the exhaust mean?!?!

[stock 87]

Your running rich.
Check to see if your choke is stuck closed.

[trousertrout666]

genius! at least compared to me, so that doesn't say much . . .

[botiejeep]

black smoke means fuel

[positrack@earthlink.]

Originally Posted by trousertrout666

I know about what white smoke and blueish smoke mean, and I know black smoke isn't good at all, but what does black smoke out of the exhaust mean?!?!

Actually, of the three, black smoke is by far the least problematic (and least expensive to fix). Like was already said, check the choke to make sure it is opening fully and adjusted properly. If that isn't the problem, you could have a real dirty air filter, a blown power valve (if it's a Holley), or a stuck power piston if it's a Q-jet. When does it smoke? If it's mainly at idle, check your idle mixture screws and turn them in (on most carbs) until the engine starts to idle a little rough, then back them out 1/2 a turn or so. Keep the total number of turns out from the seated position (screwed all the way in) even on both sides. A vacuum gauge hooked up to manifold vacuum makes this easier and more accurate. If it's flooding at idle, check your float level and needle and seat assembly. Has anyone "creatively" jetted or modified your carb? If so, that can be real fun to try to straighten out...

[trousertrout666]

it's a stock carb with no mods, the only real problem is when I rev it up from idle, smoke comes out, and when I'm on the freeway going to pass people and speeding up quickly. It isn't terrible, but I blew some smoke into some old lady's car last week at a stop light, and it was quite noticeable. The choke isn't stuck, so I think it's the idle mixture. I just can't figure out which damn screw it is on the side of the carb. THIS, I'll let a pro take care of . . .

[MochaMike]

Originally Posted by trousertrout666

it's a stock carb with no mods, the only real problem is when I rev it up from idle, smoke comes out, and when I'm on the freeway going to pass people and speeding up quickly. It isn't terrible, but I blew some smoke into some old lady's car last week at a stop light, and it was quite noticeable. The choke isn't stuck, so I think it's the idle mixture. I just can't figure out which damn screw it is on the side of the carb. THIS, I'll let a pro take care of . . .

Dude that's a screwdriver & a 20-30 minute fix at most (vs $100-500 at a shop).

You didn't post any specs & I'm too lazy to search for it, but info would be nice.
Like engine, year, carb etc. etc.....

Do a search for your carb & it will tell you everything you need to know.
When I got my Scout a few years ago (350 SBC w/Rochester 2 BBL), I knew very little about engines... The most I'd done prior to that was changing fluids, brakes, belts & fuses...

Nothing like a few books, friends & tinkering it on yourself.
I've redone everything but the bottom end.
I played with the timing & mixture to get it just where I like.

I've gotten numerous "sounds nice" complements on the trail & the street.
Not bad for 30+ stock motor & carb.

This will pay off in the long run. If you know what makes your baby pur, you won't be left stranded either on the trail or at the mall.

[trousertrout666]

Yeah, I've messed with carbs and messed with this one, but every adjustment I make doesn't seem to do anything. Where's a good place to search for info on my carb and tuning? Everywhere I search I don't find anything . . .

[positrack@earthlink.]

Originally Posted by MochaMike

Dude that's a screwdriver & a 20-30 minute fix at most (vs $100-500 at a shop).

Nothing like a few books, friends & tinkering it on yourself.

EXACTLY.

I learned much the same way. My second car (and my first hot-rod) spun a rod bearing about a month after had I finally saved up enough to get it tagged and insured. At that time, I wasn't quite 17, and my knowledge of engines was barely past the "changing oil" stage. I couldn't afford to get it fixed, so I decided to overhaul it myself (and warm it up in the process). I read absolutely everything about cars/auto mechanics I could get my hands on, I borrowed Chilton manuals from the HS library and read them during study hall, I became an information sponge around the rare few guys that actually knew what they were talking about, and I just learned as I tinkered on my own junk. I have made plenty of mistakes (and will undoubtedly make plenty more...), but at 17 I successfully rebuilt that motor with absolutely no outside help beyond casual advice from a knowledgable few. I haven't had 1 minute of formal training, but I haven't taken a vehicle to a shop since I rebuilt that motor. If I have a problem I don't know how to fix, I just learn how, and then I fix it myself. It takes time, but it really pays off in the long run.

As to your particular problem, If you want to set your idle mixture, just do it. About the only simpler adjustment you can make to a carb is setting the idle speed. Seriously, you do not need to take it to a shop for this if you are willing to attempt the job. Not that you really need it to set your idle mixture, but as general advice, get a GOOD service manual for your vehicle (look for an OLD Chiltons or a factory service manual, Haynes manuals blow ), and follow it's instructions.

If you want any further advice from us, you are going to have to POST YOUR VEHICLE SPECS. (year/make/model/engine/carb).

If you do happen to have a Q-jet, check out this links page:

http://www.florida4x4.com/tech/quadrajet/

Just remember to take most of the "performance" tips you come across with a grain of salt. Generally, on a stock or close to stock engine, the factory settings will work fine, and unless you really know what you are doing, you can get stuff so out of whack trying to "trick it out" that it may never run right again. If you set it to stock, it should run pretty good. As you become more knowledgable, you can try to improve it from there, but if you are concerned about being able to set the idle, I'd stick to the stock specs for now...

[s10er8]

what kind of carb do you have? it could the accelerator pump shooting excess fuel since its doing it when you take off. could be the float also. it might best to tear the carb down and clean it, new gaskets and float then go from there.

[trousertrout666]

sorry, didn't realize I wasn't giving enough info. to actually get assistance. It's a 22R from an '85 yota pickup(probably the simplest carb to work on) I got a manual and have started reading into adjusting carbs, the only thing I'm concerned about is that there is something wrong with the carb the needs the attention of a pro. It'll smoke sometimes, but other times it won't at all. . .

[positrack@earthlink.]

'85 'Yota... I assume that's an electronic feedback carb right? That could open up a whole new range of possibilities. I haven't had much experience with feedback carbs (at least not GOOD experiences), so I can't give you much more advice than I already did. Same principles apply, but now you've got electronic power enrichment, idle solenoids etc... Out of my element. I'd still say check the basics to start: float level, choke, etc... You might get lucky. Also, being a late model emissions carb, the idle screws are probably capped (at least they often are on domestic OEM carbs of that vintage). This might be why you are having trouble finding them. On the plus side, if they are capped, they haven't been tampered with.

How is your mileage? If the idle mixture is set right, your power enrichment circuit (power piston) might be stuck open. This would produce a rich condition at idle, off idle, and at cruise. If it is controlled with an electronic solenoid, it might be working correctly part of the time, and malfunctioning part of the time, giving you an intermittent problem. If your gas mileage is in the toilet, I'd definately check that. I'm certainly no expert on foreign machines, but your manual should give you the specifics. Study the carb section of your manual to see what this stuff is, how it works, and how you can test it. Especially if electronics are involved. Good luck.

[trousertrout666]

that's more info. than anybody's given me ever. I've got a manual, and some help, so I should be able to handle this now. At least I hope so . . . thanks