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blue smoke!!

Old 10-28-2012, 05:08 AM
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Default blue smoke!!

What's up guys? I'm sure this has been asked a thousand times but when the jeep is idling it pumps out blue smoke. I hear I need do do the heads or just valve seals. Just curious if I replace heads, will it eliminate problem completely? I'm finding a new head set at O'Reilys for $359.00 with one year warranty. Should I just pull the plug and buy it? Any input would be greatly appriciated. Thanks!
Old 10-28-2012, 05:37 AM
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Originally Posted by Torres1219
What's up guys? I'm sure this has been asked a thousand times but when the jeep is idling it pumps out blue smoke. I hear I need do do the heads or just valve seals. Just curious if I replace heads, will it eliminate problem completely? I'm finding a new head set at O'Reilys for $359.00 with one year warranty. Should I just pull the plug and buy it? Any input would be greatly appriciated. Thanks!
Not sure how to help.. are you talking about the cylinder head?
Also year, miles, and any info you feel is needed, welcome to the fourm!
Old 10-28-2012, 05:55 AM
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I'm sorry, yes the cylinder head. Its a 93 xj with what claims to be 127,000 miles but the odometer is broken. Just bought it 2 weeks ago. Doesn't appear to smoke when driving only at full stops on red lights.
Old 10-28-2012, 07:50 AM
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You need to run a compression test, both wet and dry to isolate the issue to valves or rings. But given the symptoms and not knowing the mileage, it sounds like the rings.
Old 10-28-2012, 09:44 AM
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I agree with Kalaie, unfortunatey, that does sound like worn rings. He is absolutely correct, before spending any money, get a compression test. This will tell you if you have a weak cylinder. If none of them shows lower then the others, usually want all of them within 10% of each other, then seek a cylinder leak down test. This will test the valve seats and valve guides for wear. Normally, though, worn valve guides or valve seals, will show by blue smoke when you let off the throttle. Engine creates marked vacuum at that time and oil is sucked by the worn valve guides and seals, into the cylinder and burns.

Hope this helps.
Old 10-28-2012, 01:20 PM
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Make sure your CCV system is operating and not plugged up too.
Old 10-28-2012, 02:35 PM
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Originally Posted by CCPAJeeper
I agree with Kalaie, unfortunatey, that does sound like worn rings. He is absolutely correct, before spending any money, get a compression test. This will tell you if you have a weak cylinder. If none of them shows lower then the others, usually want all of them within 10% of each other, then seek a cylinder leak down test. This will test the valve seats and valve guides for wear. Normally, though, worn valve guides or valve seals, will show by blue smoke when you let off the throttle. Engine creates marked vacuum at that time and oil is sucked by the worn valve guides and seals, into the cylinder and burns.

Hope this helps.
Sounds exactly like valve seals to me. A leakdown test would verify it.

Rings will cause smoking on both acceleration and deceleration, not just at idle.
Old 10-28-2012, 05:50 PM
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Thanks guys, taking it to the shop tomorrow and hopefully get it fixed up. I found a jeep specialist in Atlanta. I'm hoping it won't be too bad. Thanks again for your help!
Old 10-28-2012, 06:25 PM
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Originally Posted by cruiser54
Sounds exactly like valve seals to me. A leakdown test would verify it.

Rings will cause smoking on both acceleration and deceleration, not just at idle.
+1000, nailed it, as usual.
Old 10-31-2012, 05:00 PM
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Well was told engine was shot. Now I need to rebuild it, everyone is saying $4,000-$4,500. Is that the normal price on rebuild?
Old 10-31-2012, 05:32 PM
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Originally Posted by Torres1219
Well was told engine was shot. Now I need to rebuild it, everyone is saying $4,000-$4,500. Is that the normal price on rebuild?
How was it determined that the engine was shot?
Old 10-31-2012, 06:08 PM
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I would not rebuild it. No way.
You can get a whole new XJ for less than $4000.


Blue Smoke (oil)
----------------
1) Clogged CCV / oil seperator
2) Valve cover gaskets?
3) Valve GUIDE Seals
4) Valve stem seals (?)
5) High oil level
6) Worn piston rings
Old 10-31-2012, 10:10 PM
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Ok, what they said was that I didnt see the smoke while driving and that the rings are worn out. I find it crazy because for a truck thats burning oil thru cylinders and running on its last leg, it drives fine. Guy told me in mean time till I get it fixed to keep a heavy oil in it and just check the levels weekly
Old 10-31-2012, 10:24 PM
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Originally Posted by Torres1219
Ok, what they said was that I didnt see the smoke while driving and that the rings are worn out. I find it crazy because for a truck thats burning oil thru cylinders and running on its last leg, it drives fine. Guy told me in mean time till I get it fixed to keep a heavy oil in it and just check the levels weekly
Get a compression or leakdown tester and see for yourself what's up.
Old 10-31-2012, 10:25 PM
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Originally Posted by Torres1219
Ok, what they said was that I didnt see the smoke while driving and that the rings are worn out. I find it crazy because for a truck thats burning oil thru cylinders and running on its last leg, it drives fine. Guy told me in mean time till I get it fixed to keep a heavy oil in it and just check the levels weekly
Do whar Radi says and don't go to that shop anymore.

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