Black smoke on start-up

[chevychic]

Hey all,

For the last 3 weeks my truck has been blowing black smoke when I start it. It's just when I start it and not while idling or driving. I adjusted the carb over the weekend and I know I have it adjusted correctly. It was running a little rich before. I just changed the plugs today to have a somewhat fresh start with the newly adjusted carb.

It doesn't matter how warm the engine is, in fact, when it's cold, I don't notice any black smoke. But it doesn't happen ALL the time. Maybe 80% of the times I start it when it's warm.
Also when it does have black smoke, it's really stinky. It doesn't smell rich. It smells like something else is going on. The smell is kind of hard to explain. I guess the closest I can come is it smells like old burning grease. Not quite as bad as hot differential fluid but kind of similar...I think??

Another thing that might be worth noting is I have oil that comes out of the filler hole. I've replaced the PCV valve and checked the new one to make sure it was good and checked the breather hose for obstructions but all is clear.

Overall, it drives really good and has been very reliable lately. I just want to catch this problem before it gets worse and leaves me stranded someday....

Any clues?

[Mike76251]

Too me,
That is your choke coming on.
You know............making the mixture rich (or too rich?)
You might try to back off the choke a little and see if it helps.
If it is running a little rich; that's better than running lean.

[Moloko]

Yeah, but running very rich can be very bad. Thats why I have to rebuild my Chevelle engine. I took the pistons out yesterday, or rather they fell out, since the cylinder walls were so washed with gas.

[Prerunner1982]

ok, heather and myself discussed this last night.. whats with the oil coming out of the breather and pcv? i am having the same problem. and have replaced the pcv..... breather clogged maybe?

[swervin ervin]

The oil coming out of the breather is a sign of worn rings most of the time. It's called blow by. Does it blow oil out or just build up over a period of time? Does it smoke out of the valve cover breather?

[Prerunner1982]

as far as mine, it appears to blow oil as it covers everything on both sides.. and yes it comes out the breather...

[chevychic]

mine blows oil too. Mainly on the side with the filler hole. I can't keep anything on that side of my engine compartment clean because of it.
I have a bit of seepage out of the breather hole that appears to be build up, but its blowing out of the filler hole.

[1FaastC10]

if you've literally got oil blowing out of the valve cover openings, to the point of oil all over everything on that side of the engine, it may be time to start saving for a new engine, or rebuild the one you have. do any of your mechanic buddies have an air compressor that you have access to? if so, get ahold of a leakdown tester, and run a leakdown test. that will tell you the quality of the ring seal. my guess is, its not healthy. it still may be healthy enough to run, and get you where you need to go reliably, just make sure to keep an eye on your oil level.

oh yeah, if you do decide to do any major work to the engine, please take lots of pics. there's nothing sexier than a woman grease covered and elbow deep in an engine.