oil leak-pcv system? help!
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Originally Posted by Radi
Good. Out of curiosity, are you certain the oil is coming from the dipstick tube and not the more-common oil filter adapter leak? They're pretty close together. You said the oil is staying out of the air filter box now? I'm thinking your CCV is probably working correctly then.
Oil blowing out of the dipstick tube with a properly functioning CCV might indicate other problems, ie: worn rings causing excessive blowby. OTOH a leak from the filter adapter just means the adapter is loose or the o-rings are shot.
What happens if you remove the oil filler cap with the engine running? Do you get smoke or vapor puffing out the filler?
There shouldn't be any pressure there, if anything a slight vacuum.
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Your rings are probably getting a bit tired, allowing more pressure to escape into the crankcase than the CCV system can remove. It's just part of the joy of an older motor, nothing to stay awake at night over. Just keep up with the oil changes as the blowby does contaminate the oil a bit faster.
Last edited by Radi; 04-18-2012 at 12:10 AM.
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Originally Posted by Radi
That whiteish smoke is compression blowby. There will be a small amount of water vapor in there until the engine oil heats up enough to drive it out. If you drive mostly short trips the oil may never get hot enough.
Your rings are probably getting a bit tired, allowing more pressure to escape into the crankcase than the CCV system can remove. It's just part of the joy of an older motor, nothing to stay awake at night over. Just keep up with the oil changes as the blowby does contaminate the oil a bit faster.
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There will always be some condensation going on when metal is heated, cooled, heated, cooled...that leaves a small amount of water in the oil. You really see it here where we have "winter", lol. White sludge under the oil filler cap. When the oil heats up that water evaporates creating the whitish smoke. It should go away after the motor runs at operating temp for a while.
When you have excessive blowby, what you are really getting is a bit of gasoline and a bit of exhaust pumped past the rings and right into the oil pan... regular oil changes are even more important than usual. It'll run a long time yet provided you keep the oil clean.
Rings aren't too bad to change in this motor. Problem is by the time the rings wear due to age, the cylinder walls, crank, bearings, cam, lifters, valves, timing chain/gears and everything else are also worn. You can do a 40K mile "rebuild", just brushing the cylinders and snapping in rings and bearings, or a 200K mile rebuild, resurfacing/replacing worn parts from top to bottom. There's really no free lunch with worn metal.
This motor lends itself very well to DIY, it's an easy rebuild. Heck, I think I can rebuild a 4.0 in less time than it takes me to remove and disassemble a Northstar.
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Last edited by Radi; 04-18-2012 at 01:12 AM.
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Originally Posted by Radi
There will always be some condensation going on when metal is heated, cooled, heated, cooled...that leaves a small amount of water in the oil. You really see it here where we have "winter", lol. White sludge under the oil filler cap. When the oil heats up that water evaporates creating the whitish smoke. It should go away after the motor runs at operating temp for a while.
When you have excessive blowby, you are also getting a bit of gasoline and a bit of exhaust pumped right into the oil pan... regular oil changes are even more important that usual. It'll run a long time yet provided you keep the oil clean.
Rings aren't too bad to change in this motor. Problem is when the rings wear due to age, the cylinder walls, crank, bearings, cam, lifters and everything else is also worn. You can do a 40K mile "rebuild", just brushing the cylinders and snapping in rings and bearings, or a 200K mile rebuild, resurfacing/replacing worn parts from top to bottom. There's really no free lunch with worn metal.
This motor lends itself very well to DIY, it's an easy rebuild. Heck, I think I can rebuild a 4.0 in less time than it takes me to remove and disassemble a Northstar.
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Another question, is there a way to stop or slow the flow of oil into the air box now? Its not that bad but still.
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You could splice one of those plastic fuel filters inline and toss it when it starts to get full. Some folks run an old-style draft tube down under the axle, but that leaves oil all over your driveway, and does nothing to filter the incoming air should it breathe in instead of blow. Or just wipe it out every so often.
As long as it isn't enough to foul your plugs, it's not harming anything.
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Originally Posted by Radi
If the CCV lines and elbows are all clean and you're still getting it- there really isn't a simple fix. It's another one of those "features" of an older 4.0.
You could splice one of those plastic fuel filters inline and toss it when it starts to get full. Some folks run an old-style draft tube down under the axle, but that leaves oil all over your driveway, and does nothing to filter the incoming air should it breathe in instead of blow. Or just wipe it out every so often.
As long as it isn't enough to foul your plugs, it's not harming anything.
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Well it's leaking now from the dipstick again. And I'm almost 100 %sure that's we're it's commin from. I don't know why could it be because of my bad rings? Or is something else clogged causing this. I did a coolant flush befor I had all these problems. Heeeeeeeeelp
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I think you're at the point of needing to run a compression or leakdown test to check the rings. I suppose that fuel filter added just enough backpressure to make the dipstick tube a more attractive outlet for the blowby.
How much of the engine's history do you know? Any chance it was neglected before you got it, where the rings might be stuck instead of worn?
How much of the engine's history do you know? Any chance it was neglected before you got it, where the rings might be stuck instead of worn?
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Originally Posted by Radi
I think you're at the point of needing to run a compression or leakdown test to check the rings. I suppose that fuel filter added just enough backpressure to make the dipstick tube a more attractive outlet for the blowby.
How much of the engine's history do you know? Any chance it was neglected before you got it, where the rings might be stuck instead of worn?
How much of the engine's history do you know? Any chance it was neglected before you got it, where the rings might be stuck instead of worn?
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