Hey guys, I've got a 1968 mustang with a 200 inline 6. About 2 weeks ago, I was leaving work and I turned the car on, and as I was pulling out of the parking lot and got on the gas a little, a bunch of white smoke was coming out of my hood vents. So when I got home I saw that the hose that goes from my oil cap to my air cleaner was disconnected, so I conected it back up and now there is no more noticible smoke while driving. But now, I am finding oil inside of the air cleaner, lots of smoke coming out of the dipstick, lots of smoke coming out of the pcv port on the valve cover when I remove the pcv valve while the car is running, and there is no suction on the oil filler on the valve cover and smoke is coming out of it instead. I just replaced the valve cover gasket thinking it could've been that, but I am still having the same problem. Any ideas of what it could be? When I take the pcv valve off of the car while it's running, and put my finger to the end of it, it's still got lots of suction, so I don't think it would be clogged. Any help would be appreciated because it currently is my daily driver and I don't want to make the problem worse than it is by driving it around even more.
Oil smoke coming out of dipstick
Nathanamaya
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Hey guys, I've got a 1968 mustang with a 200 inline 6. About 2 weeks ago, I was leaving work and I turned the car on, and as I was pulling out of the parking lot and got on the gas a little, a bunch of white smoke was coming out of my hood vents. So when I got home I saw that the hose that goes from my oil cap to my air cleaner was disconnected, so I conected it back up and now there is no more noticible smoke while driving. But now, I am finding oil inside of the air cleaner, lots of smoke coming out of the dipstick, lots of smoke coming out of the pcv port on the valve cover when I remove the pcv valve while the car is running, and there is no suction on the oil filler on the valve cover and smoke is coming out of it instead. I just replaced the valve cover gasket thinking it could've been that, but I am still having the same problem. Any ideas of what it could be? When I take the pcv valve off of the car while it's running, and put my finger to the end of it, it's still got lots of suction, so I don't think it would be clogged. Any help would be appreciated because it currently is my daily driver and I don't want to make the problem worse than it is by driving it around even more.
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What's happening, is the amount of blow-by is exceeding the amount the PCV can handle, which causes positive crankcase pressure, which in turn forces crankcase vapors or oil to leak. This is most likely due to worn piston rings and cylinder wall wear, the only real fix is to rebuild the motor. You can try cleaning the PCV which may make some improvement, but it won't be very significant. Changing the oil may help. You could also replace the PCV with one for an engine with more CID, but again it is not a big change. And lastly, you can just live with it, and change the air filter more often. My 2 cts. Good Luck.
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You might also try connecting your PCV directly to the full intake vacuum instead of the air cleaner. However if you are getting a huge amount of blowby this may increase your idle speed too high. If that's the case, a rebuild is the only option.
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I'm thinking this is backwards, and that the line to the air filter just draws filtered air through the crankcase (normally anyway; probably not in this case). The PCV valve is in the line hooked to engine vacuum. At least that's the way it is in my '66, although the fresh air side isn't connected to the air filter.
If the PCV valve is working and you have vacuum on it, then I'm afraid the comments about too much blow-by for it to handle are probably right.
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Yes, Charles, you are correct. The PCV valves are not connected to the air cleaner but to manifold vacuum through the adapter under the carb. The valves are nearly closed at idle and draw very little of anything. At idle they can't cope with excessive blowby which will find its way outside through any available opening such as breather cap and/or dipstick tube.
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Thanks for all the help and info guys. Was hoping I wouldn't have to do a full rebuild, but it makes me feel a bit better knowing what the problem is now. On the bright side, she'll be running better than ever with this rebuild ? Thanks again for all the info guys, really appreciate it!
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Older models had the PCV hooked up to the intake: full vacuum. That's the way my '64 TBird is set up. Later years they used partial vacuum, as in the air cleaner. At idle, air cleaner vacuum is low, while manifold vacuum is high.
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Technically the PCV should be connected to a plate under the carburetor, so even when manifold vacuum is low (acceleration), there is air flow through the throats of the carb into the intake manifold, and the plate with its openings will still have a draft, or at least that's the way I understand it. I have never hooked anything to it that would check the flow. And my understanding of the filter and the tube from the valve cover to the air breather, was due to the emission changes, which made any blow-by the PCV system could not take care of be burned in the engine, instead of being released in the atmosphere. My 2 cts. Good Luck.
Nathanamaya,
"Technically" you probably have a broken ring or ring land , or at least severely worn. When crankcase pressure is extreme , it is because the rings are not doing their job. If "I" were in you position , I would be building ( or buying a rebuilt) one to replace the one in the car. A 6 cylinder can be swapped in a weekend by an amature , no problem. The smoking isn't going to magically stop.
"Technically" you probably have a broken ring or ring land , or at least severely worn. When crankcase pressure is extreme , it is because the rings are not doing their job. If "I" were in you position , I would be building ( or buying a rebuilt) one to replace the one in the car. A 6 cylinder can be swapped in a weekend by an amature , no problem. The smoking isn't going to magically stop.
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