head gasket or piston rings?
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head gasket or piston rings?
I have a ton of pressure in my valve cover, and when driven I'm assuming the pressure causes the dipstick to come out and blow oil everywhere. With that in mind does that seem more like a head gasket or piston ring problem? I'm pretty sure my rings aren't in great condition considering the fact that my spark plugs are always covered in oil and my jeep burns the oil very quickly. And I have seen it smoke lately, and it seems to me to be white smoke, I've always had some coming from the oil cap but now it's blowing from the exhaust when I crank it and give it gas. But does the oil burning seem more like a valve problem?
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A leak down test would determine the cause.You can not tell just by looking at it and guessing.It could be your rings or it could be valve seals,valve guides or a combination of any of that. There is no way to be sure with out doing some tests. I would start with the leak down test.
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Okay, thank you. I'm gonna give that a shot. I don't know if it has to do with either of those things but I also have a TON of blow by that has literally turned my air filter black. and so far I haven't seen any milky oil or anything. I haven't tried the leak down before though, I have done a compression test before and all the cylinders except for maybe one, were way off where their supposed to be.
Thanks for the reply!
Thanks for the reply!
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I may have jumped ahead a bit. Check what Scott mentioned and see if that helps.
Also if you are getting oil in your cylinders it will mess up your compression readings.
Also if you are getting oil in your cylinders it will mess up your compression readings.
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#7
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None have a PCV valve. It's a CCV system.
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If you have a bunch of case pressure and it's vented right it's probably blow-by. How many miles? Pull all the plugs and check comp. warm. I like 7 strokes. Then add a couple cap-fulls of oil & do it again. Those two sets of 6 numbers will help decide where to go from there.
A few feet of clear vinyl tube makes a handy way to measure, (sort of) 2 or three tablespoons of oil and blow it in there.
There was such a thing as a "road draft tube" (for that stuff which is now going into your air cleaner) I had one that was metal and went just past the motor mount down there. Was cut at a 45* so air could cause a little suction cruzen.
Edit...Blow-by the rings, I'm sure it DOES happen!
A few feet of clear vinyl tube makes a handy way to measure, (sort of) 2 or three tablespoons of oil and blow it in there.
There was such a thing as a "road draft tube" (for that stuff which is now going into your air cleaner) I had one that was metal and went just past the motor mount down there. Was cut at a 45* so air could cause a little suction cruzen.
Edit...Blow-by the rings, I'm sure it DOES happen!
Last edited by DFlintstone; 10-25-2011 at 11:49 PM.
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[QUOTE=Spoonman;1281077]I don't think that worn rings would raise crank case pressure.
Most certainly will. The cylinder pressure goes past the rings and pressures up the crankcase. That's why it's caused "blow-by".
A dry, then wet compression test will determine if it's rings.
To the OP: Can you feel the pressure or are you just getting oil in the air cleaner?
Most certainly will. The cylinder pressure goes past the rings and pressures up the crankcase. That's why it's caused "blow-by".
A dry, then wet compression test will determine if it's rings.
To the OP: Can you feel the pressure or are you just getting oil in the air cleaner?
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To the OP: Can you feel the pressure or are you just getting oil in the air cleaner?[/QUOTE]
Yeah, definitely. If I place my hand over the oil cap with it off I can feel alot of pressure, enough to move the oil cap if I just place it over the hole.
I appreciate all the feedback guys. I wanna do the leak down test also, as soon as I can find an air compressor.
Yeah, definitely. If I place my hand over the oil cap with it off I can feel alot of pressure, enough to move the oil cap if I just place it over the hole.
I appreciate all the feedback guys. I wanna do the leak down test also, as soon as I can find an air compressor.
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There's also a "dynamic compression" test. Could be looked up. Idling warm you unplug, (then re plug), plug wires one at a time from the dist, note the rpm drop. Then you can do it again at a higher rpm. Again you'd get two sets of 6#'s that can help with figuring it out. They must sell a short block for these?
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There's also a "dynamic compression" test. Could be looked up. Idling warm you unplug, (then re plug), plug wires one at a time from the dist, note the rpm drop. Then you can do it again at a higher rpm. Again you'd get two sets of 6#'s that can help with figuring it out. They must sell a short block for these?
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Gotch'ya /\...had meant to wright "another set of 6#". Got curious and looked at Ebay. This outfit in Texas does have good feedback. $900 short block;
http://www.ebay.com/itm/4-0-242-Jeep...item3a6b37dba7
http://www.ebay.com/itm/4-0-242-Jeep...item3a6b37dba7
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Wether it's rings or head gasket you're at least going to have to take the head off to do either repair, so start by doing that. If it's a head gasket, replace it. If not then start looking for another motor.
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