Cold start...too much smoke?

[oneday1]

So I've searched the forum with not too much luck to try and find an answer to my question so I'll go ahead and ask.

When I start my truck after sitting overnight it will start and run fine but after about 30 seconds it starts pumping a good deal of smoke out of the tailpipe. I'm thinking when it warms up enough to activate the choke? The smoke increases for a bit and then after about 5 minutes will stop.

Video here: http://youtu.be/r_3oWINPMY0

Can run the truck all day and never see that amount again even if stopped for an hour or so. Only happens on cold starts. And cold is relative, doesn't get much below 40 here. This is a fairly recent development and although I have done a few things to the truck (full fluid changes, rebuilt carb, normal tune up stuff) I haven't opened up or worked on the engine at all. I do believe it's running a little rich but would that be the cause? No emissions control stuff on this truck at all if that is important. It doesn't seem like a huge deal but since it's a recent development I don't want to miss something big that might be waiting to fail. Thanks in advance for the help!

[Malo83]

My 83 does the same, first start in the morning after sitting overnite, I believe my valve guide seals are bad/worn, once the oil is burned off she's good the rest of the day,no smoke

[Zane M]

Valve guide seals would be my guess(smoke doesn't look black, more blue).
Your initial start up will burn off the oil that has seeped past the seals. That will continue for a bit until things warm up and the oil burns off.

[lha1992]

That looks like condensation. It'll do it til the truck is warmed up then go away.

Mine gives off a puff of blue smoke also because its got worn valve guides too. An when its cold outside it'll give off condensation an then go away after a Lil driving.

[cardreams]

but a bottle of locus in it it will stop it

[oneday1]

Thanks all!! Was thinking valve seals as a possibility. Didn't think gasket leak since the smoke doesn't have a sweet smell like coolant but was hoping for some outside input. Thinking too much makes me crazy! Have been putting off digging into the engine much since it's pretty much my daily driver and don't want to put it out of commission for too long. I have a few days off coming up though so I guess it's time. Thanks again!

[Malo83]

Mines been this way for a few years, like you it's my DD, i'm in no hurry right now but when the time comes i'll invest in some new complete rebuilt heads

[motornut]

1978 Jimmy cold start 02 - YouTube

most of mine clears up....

[dieseldawg142]

i'd say it sure looks like your valve seals. had the same prob in my '90, after changing them, no smoke at all.
their pretty cheap to buy, but will take you awhile to install.
i would recommend you get a air hose you can thread into your spark plug hole to keep the valves up. i didn't have one, so i brought each piston to tdc, then stuffed a long piece of 1/4 rope in the hole so i wouldn't lose the valves. time consuming!
you might want to address it soon. after mine came out, couldn't belive how brittle they were