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Bad Compression

Old Nov 3, 2009 | 05:17 PM
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Default Bad Compression

I have bad compression in my fourth cylinder(25psi).Oil does smell like gas.I think my rings are bad but im no mechanic.
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Old Nov 4, 2009 | 01:28 AM
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is this a question or a statement. Are you wanting advice?????????? Gotta give a little to get a little there buddy!
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Old Nov 4, 2009 | 12:54 PM
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well gearheadette told me it could prob be a fuel pressure regulator that get gas in the oil so it goes past the rings easier.I just wanna know if its something else besides my piston rings or if its them at all.Like what should i check?
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Old Nov 4, 2009 | 02:17 PM
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How do the rest of the cylinders look? if they are all good above 120 then it could be a bad valve or blowen head gasket. If the comp is low on the others then it could be bad rings,need just a bit more info.
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Old Nov 4, 2009 | 08:09 PM
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I think it was 150 in all the others.It dont run hot just runs bad and smoke alot.there is no water in the oil so i dont think the head gasket is blown.
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Old Nov 5, 2009 | 06:49 AM
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how does your exausht look or smell?
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Old Nov 7, 2009 | 11:47 AM
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Originally Posted by gearheadette
how does your exausht look or smell?
well i took the muffler off my exhaust so its loud and im not sure how it smells.I need to record a video of how it runs and let yall listen to it cause its bad lol
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Old Nov 16, 2009 | 12:57 PM
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Here are the compression test results
1-75
2-110
3-150
4-25
5-150
6-150
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Old Nov 16, 2009 | 01:06 PM
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I would do a pressure test on your cooling system to make sure it is not a headgasket problem. But I think you either have valves going bad or rings. On the cylinders that are low use an oil squirt can and put about 3 suirts of oil in the cylinder and check them again and see if the compression comes up,if it does it is rings,(Engine should be warm if you can).if it does not it is either valves or a gasket leak.
How long has your muffler been Off?
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Old Nov 16, 2009 | 01:10 PM
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I put some oil in the bad cylinder and it went up.Guess my rings are bad.O well i will let it sit out there and rot lol. My muffler has been off for awhile but i dont really drive my jeep
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Old Nov 16, 2009 | 01:14 PM
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You can let it sit,but do not let it rot,someday it will be a classic.
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Old Nov 16, 2009 | 01:19 PM
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lol yea one day i will have it running right.Thinkin about just goin to the pull-a-part and gettin a whole motor.They have 85-01 cherokees.And i can get the motor for 125 w/o warranty and about 155 with warranty.Now what would be a good year to get a motor from?
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Old Nov 16, 2009 | 01:50 PM
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Direct fit from an 87-90,or you could use a motor from a 87 and up,just would have to use the longblock after 91 and all your bolt ons,like dist,intake/exhaust,flexplate,etc.
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Old Nov 16, 2009 | 01:58 PM
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so your saying 87-90 will just drop right in and bolt up to what i got and 91+ wont bolt up.Also is there and other jeep models i can use the motor out of?I want to just drop it in no modification needed.
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Old Dec 1, 2009 | 02:38 PM
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Is there anything i can put into my cylinder to help keep good compression long enough till i blow it up?
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