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Tips

smoke out of tail pipe

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AN5Sprite said:
My .02

If you've already done a leak-down, why not do a compression test as well? If you do have coolant getting into a cylinder a compression test will show you. You'll have a much higher reading on the offending cylinder, and probably water in you compression tester. If that winds up to be the case with a little light you'll probably be able to see coolant sitting on top of a piston too. If none of that happens I would think you could rule the head gasket out.

Also, if you're not sure what's coming out of the tailpipe, hold a piece of paper up to it. If it's H20 you'll know quickly.
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haven't seen any water in the cylinders even after turning over the engine for a compression test.
 
Boink said:
It might be steam... but I'll also add again, white smoke (though not bright white) isn't always steam. Steam will linger for a long time in the air when mixed with exhaust. "White" smoke is often a very light grey smoke and can be due to a LOT of oil (and it won't be blue until it becomes dilute). I've seen this on my own 1275 when the PCV valve gulped a relatively small amount of oil directly into the intake manifold... and it took several minutes to burn off. That was very smoky and it wasn't black at all; in fact, it looked rather white. :smile:

See if a shop can verify combustion gases in the coolant. Combining that with the leak-down test (and the fact that you're not losing any coolant), and I might turn to something else. BTW, does the oil look normal?
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but I did a leak down test with the radiator cap off and did see any bubles or feel any air coming out of it. I did feel air coming out of dipstick and valve cover as only source of leaking air (all cylinders recorded 20-25% leakage).
 
How long are you letting the car run? Is it getting up to temp and are you driving it or is it in the driveway? I run into the old gas problems with boat motors and with ethanol used in the gas it seems to attract water. I get a white steam out of the exhaust for 5 to 15 minutes after the engine starts. Is it possible that the Weber has a little too much varnish from sitting and its causing it to run rich? If the car is able to go on the road I'd be inclined to drive it for an hour or so and see if the problem goes away.
Rut
 
Rut said:
How long are you letting the car run? Is it getting up to temp and are you driving it or is it in the driveway? I run into the old gas problems with boat motors and with ethanol used in the gas it seems to attract water. I get a white steam out of the exhaust for 5 to 15 minutes after the engine starts. Is it possible that the Weber has a little too much varnish from sitting and its causing it to run rich? If the car is able to go on the road I'd be inclined to drive it for an hour or so and see if the problem goes away.
Rut
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I let the car run for about 20 minutes in the drive way. It was able to get up to running temp, even when at running temp (water thermostat open), I still have the smoke coming out. I did put some fuel stabilizer in it in September last year after the last drive (tank has about 1/3 full of gas).
 
Hmmm... perplexing. Could there be a crack in the block such that you're allowing oil into the intake?
 
AN5Sprite said:
My .02

If you've already done a leak-down, why not do a compression test as well? If you do have coolant getting into a cylinder a compression test will show you. You'll have a much higher reading on the offending cylinder, and probably water in you compression tester. If that winds up to be the case with a little light you'll probably be able to see coolant sitting on top of a piston too. If none of that happens I would think you could rule the head gasket out.

Also, if you're not sure what's coming out of the tailpipe, hold a piece of paper up to it. If it's H20 you'll know quickly.
Click to expand...

I did a compression test on a warmed up engine and saw 150 psi on all cylinders.
In a test I also ran the engine with the hose that goes from the valve cover back to the intake of the carb (in case it is gulping oil), and this did nothing.
In removing the spark plugs on all cylinders, all spark plugs are black with soot and smell of fuel.
I also filled up the tank full of fuel (originally it was about 1/3 full) in case the fuel is old, no difference.
Do see any bubles in the radiator. Also with the radiator cap removed I don't see coolent being pushed out (even when reving the engine).
 
replaced the fuel filter and sprayed carb clean in the carb. Still have problems. Thinking it might be the gas or carb causing the issue of the smoke out the tale pipe.
 
Hard to tell from here, but it sounds to me like you need to drive it enough to run a couple tanks of gas through.
 
Those sooty plugs and smell of gas still point us to carburation and/or gas.
 
Why would the plugs be black and exhaust be greyish/whitish? I do remember shecking the plugs last summer before having this issue and they were normal.
 
I think that just getting the water temp up in the driveway isn't enough to show you what's going on.

You haven't found a major problem with compression/leak tests, I assume there are no bad knocking/grinding/rattling noises and your oil pressure is good... If you had a really bad case fuel phase separation I think you'd have a car that wouldn't run at all. That gas is old though and could be bad-ish. If it were me, I'd check the ignition system, maybe start with some fresh plugs, put in some fresh high octane fuel and DRIVE.
 
Steve X2...
 
The car has been sitting for a while. You've change fluids and radiator. If radiator was bad and now you have a new one maybe up to pressure. But, that will not affect carb. Maybe the smoke you see is old vapor that has been sitting in the mufflers for 3 months. I do a radiator pressure test for leaks. Thermostat for what temp? Warm carb up real good, change plugs and refire ( while warm ) and run for a while then check again. I do believe that 3 & 4 could be the coldest cylinders until warmed up good. Use a coolant sniffer in tailpipe before teardown to eliminate coolant. If all is the same with no overheating rejet carb.
 
see link below, this is not my car, but this is about how much smoke is coming out, even with engine sitting in driveway warmed up to operating temp. I have ran it for about 20-30 minutes and it still looks like it. When idleing it is not this much smoke, but when engine is revved up about the same amount of smoke is coming out as shown in the picture from the link below (also about the same color). Spark plugs sooty black. I am running on the idea that there was some separation of the ethanol and more of the ethanol that typical is going through the engine, which therefore more vapor is coming out of the exhaust. I plan to drain some of the fuel (to hopefully get out this bottom layar) and then drive the car to eventully fill up with fresh fuel.
https://www.chemistryland.com/CHM107Lab/Exp02_Exhaust/ExhaustVapor.jpg
 
I don't know the temp in Oregon but that much vapor is coolant if 50 deg and up. Alcohol in the fuel seperating has nothing to do with it as the engine will not burn water which what would be at the bottom of the tank on fuel/water/alcohol seperation. Temp and rich fuel is reason for plugs. Engine if not to temperature will not burn off plugs. Try new plugs and DRIVE until up to temp then check plugs. Pressure test rad. or do leak down for coolant check. OR go to NAPA and get the tester set for checking antifreeze in exhaust. If driven until warm and plugs are checked and one is clean, might be the area to start looking.
 
LarryK said:
I don't know the temp in Oregon but that much vapor is coolant if 50 deg and up. Alcohol in the fuel seperating has nothing to do with it as the engine will not burn water which what would be at the bottom of the tank on fuel/water/alcohol seperation. Temp and rich fuel is reason for plugs. Engine if not to temperature will not burn off plugs. Try new plugs and DRIVE until up to temp then check plugs. Pressure test rad. or do leak down for coolant check. OR go to NAPA and get the tester set for checking antifreeze in exhaust. If driven until warm and plugs are checked and one is clean, might be the area to start looking.
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Already did a compression test (150 psi on all 4 cylinders) and did a leak down test (20% leakage on all 4 cylinders, and didn't see any bubbles or hear (with a hose to my ear) any air come out of radiator, all leakage was coming out of dipstick and rocker cover).
 
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did all the testing and troubleshooting I could. Went for a short drive down the highway (about 5 miles), during the drive exhaust was clear. After getting back home, revved the engine in the drive way and the exhaust was still clear.
 
Now, after the drive ( while warm ) check the plugs and see if they cleared. If not, change plugs ( or clean ) and drive and check plugs for soot. Hopefully, it will clear itself on just being warmed up. When restarted after a cool-down does it smoke?
 
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