Smoke out of the passenger tail pipe - HELP!

[kajf9491]

Alright ladies & Gents,

I just got my truck running again, and for some reason there is a good amount of smoke coming out of the passenger exhaust. There is a little out the driver side but nothing I wouldn't call abnormal. The passenger side however leaves a pretty good cloud if it's sitting running for a couple of minutes. I apologize for what is about to be a long winded history of my truck, but I feel like some of this may be important for helping diagnose my problem. I had the truck running & driving but certainly not road worthy. Had to deal with some electrical clean-up and do some odds and ends like install fuel pressure gage and tachometer so I can diagnose the truck a little. Long story short it ended up sitting a little while and I went through the all too common carburetor issues of fuel turning to varnish. Once cleaned, I found out my floats had holes in them somehow, so I replaced those. Finally got the truck up and running today and for some reason there is much more smoke coming out of the passenger exhaust than there ever has been. There was also a louder clicking noise coming from the passenger side of the engine while it was running. I assumed that for some reason I needed to check my valve lash. As I did the standard "loosen until you hear it click then tighten a 1/4 turn process" it started smoking more out of the exhaust. I got all of the valves adjusted and the loud rattling went away but now it's smoking more. I've been reading that if it's white smoke it means there's coolant/water getting in the oil and if it's bluefish it's burning oil but I honestly can't tell. Just looks like smoke to me. Doesn't really seem to have a distinctive smell to it either. This is troublesome to me because I didn't have this problem when the truck last ran, and I didn't touch anything except some wiring and the carburetor. Oh, I must mention I did start using ethanol free gasoline as well. I tried taking pictures and those didn't really work that well, so I took a quick video and have posted it to youtube. If you'd be kind enough to chime in and make any suggestions, I'd appreciate it. (Please ignore the rust!)
https://youtu.be/-3Dusp2cOLY

[davepl]

Combustion pressure is far higher than cooling system pressure, so if you have a head gasket leak between the coolant and the combustion chamber, you're not only going to get a little water in the cylinder, you're going to get exhaust in the coolant.

While it's still cool (not hot) start it up without the radiator cap. Get the fluid level high enough that its over the core so you can see it, and look for bubbles. That'd be a symptom of a head gasket leak.

Simply being lean can cause whitish smoke and a distinctive smell, but not clouds of it or anything. I'm not sure how much smoke you're seeing, so it's hard to say.

[70STOVEBOLT]

Two seconds is not long enough to tell anything. Can you take a longer video? It appears to be bluish, but need to see more. How long did it sit for?

[kajf9491]

Thanks Davepl. I'll try looking at the coolant as you recommended.

Sorry for the short video. I'll try uploading a longer video tomorrow when it's light out again.

[cleszkie]

If the smoke got worse after you adjusted the valves, it could be bad valve guides. When you adjusted the vavles, a chunk of brittle guide may have come loose.

If you put your hand in front of the exhaust as its running, and your hand gets very wet, you got either a bad head gasket or more unlikely, a cracked head or block.

[kwmech]

You have an automatic trans?

[n33k0]

Originally Posted by cleszkie

If you put your hand in front of the exhaust as its running, and your hand gets very wet, you got either a bad head gasket or more unlikely, a cracked head or block.

A little water coming out of the exhaust when the engine is cold isn't anything to worry about, right? As long as there isn't water constantly coming out of the exhaust after the engine has warmed up.

[NoNeck]

If the truck sat long enough for the fuel to varnish, it could be a collapsed lifter. If you had a valve train rattle on start up that wasn't there before it sat, the lifter(s) can drain all of the oil from them. This would cause a valve lifter noise, but it should go away once the lifter fills with oil. That could take a few minutes while the oil pressure builds.

One other thing could be the valve seals. They tend to really dry out if not lubricated frequently. If they are dry and brittle oil on that head could be dripping into the combustion chamber.

As cleszkie said, valve seats would be another cause. An old, plugged PCV valve would be another.

POP

[NoNeck]

Oh, one more... clogged oil return holes in the heads could fill the valve cover with too much oil, pushing it past the valve seals/guides, too.

If the oil is full of sludge, SeaFoam might be in order here.

POP

[67 chevelle]

Originally Posted by kajf9491

Alright ladies & Gents,

it ended up sitting a little while and I went through the all too common carburetor issues of fuel turning to varnish.
https://youtu.be/-3Dusp2cOLY

with this in mind , my first thought would be valve seals , the water out the exhaust can also be from the same thing , sitting and not running for awhile , that will burn off after a few hours of operation , if it were me and the engine was high mileage , Id remove heads and have them rebuilt

[davepl]

Originally Posted by kwmech

You have an automatic trans?

I bet you're thinking it's pulling trans fluid through the vacuum line to the modulator valve? Good idea!

Check the vacuum line for any signs of oily residue if you do have one...

[kwmech]

Yup! if the modulator goes out it will pull most of the fluid into #8 cylinder and a small portion into #5.

[old Chevy guy]

Originally Posted by kwmech

Yup! if the modulator goes out it will pull most of the fluid into #8 cylinder and a small portion into #5.

X's 2 . Been there seen that on a few vehicles.

[kajf9491]

Thanks to all of you who have chimed in already to try and help me out. Here's what I was able to check tonight.

- Put my hand under exhaust and it didn't seem to get wet or moist.
- Topped off the coolant, and let it warm up with the radiator cap off. Didn't notice any bubbles forming or rising to the top.
- Let it run for about 20 minutes, didn't really seem to increase or reduce the amount of smoke.
-Checked the vacuum lines going to the carburetor and all seemed to be dry inside.

I did take two more videos that are longer than my original and show the issues a little better. The one is out of focus (sorry) but shows the amount of smoke coming out pretty well.
1st Video: Engine Idle & Rev https://youtu.be/PF7Dmygc66Y

2nd Video: https://youtu.be/IPeodSxgKdA

[cleszkie]

As mentioned by a few others, if you have an auto tranny, pull the rubber vacuum line off the back of the modulator on the rear passenger side of the tranny housing and look/feel for tranny fluid (ATF). If you find some there, then its a good bet that AFT has been sucked up into your intake manifold and burned in you engine. That vacuum line should be dry. If its wet inside, your modulator is toast.

[kajf9491]

I have a 700R4 installed in my truck, so I don't think I have a vacuum modulator. Correct me if I'll wrong, but that probably eliminates that as a culprit.

[kwmech]

Originally Posted by kajf9491

i have a 700r4 installed in my truck, so i don't think i have a vacuum modulator. Correct me if i'll wrong, but that probably eliminates that as a culprit.

yup

[snipescastle2]

if the heads are factory, I.E. never been rebuilt, chances are they have the cheapo "O" ring stem seals. those get brittle and break after a while, causing abnormal oil consumption. Might be time to change over to a nice set of umbrella stem seals or positive type stem seals, however, most of the positive type require machining of the valve guide on the heads.....just thought I'd mention that.....
Ben

[fwayne]

By now you've run it enough to check the spark plugs. Pul those on the smoking bank. If it's oil, those are going to show buildup. If its water, or ATF they will be very clean, if not too clean. Just google "how to read a spark plug color" and you'll find the age old images that tell the story.

Oil can come from leaking intake gaskets too.

One thing I had happen was brake fluid being sucked into the intake from the brake booster, and the booster was filled with fluid from the leaking master cylinder. It smoked a lot with very little observed fluid loss.

I've alway been told that if it smokes under acceleration, its rings, if it smokes most under decelleration (downshift with no throttle) its the valve guides.