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  #1  
Old 03-20-2011, 11:28 AM
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02 Overland

Hello everyone,

New to the site and loving it so far. I just bought a 2002 Overland with 155,000 miles on it that is SUPER clean. Only problem is the 4.7 HO under the hood runs but only on about half the cyl's. Seems to be making quite a bit of noise from the top end. I only ran it for a min or so. I have no idea how long the last owner ran it. I am unfamiliar with this engine. The last one I had was a 4.0. Can someone lead me in the right direction with this thing before I tear into it?

I only paid $1000 for it and figured it was atleast worth that.

Thanks in advance for any info on the gremlins in the 4.7 HO
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Old 03-20-2011, 03:21 PM
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Re: 02 Overland

Welcome to the garage.
You have to remove the cylinder head covers and check for out of place rocker arms. Seems that sometimes a valve guide can drop, for whatever reason i don't know. Don't run it anymore before you know what is wrong, you will do more damage to it.
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Old 03-20-2011, 04:20 PM
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Re: 02 Overland

Welcome! Awesome Deal! Good Luck with everything!
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Old 03-20-2011, 06:00 PM
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Re: 02 Overland

So is there a chance of the valves hitting the pistons? Or is it just a valve train issue? I just hope the previous owner didn't run it much.

I will post up some pics of it soon.

Thanks for the info so far.
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Old 03-20-2011, 06:49 PM
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Re: 02 Overland

Welcome to the forum!! Post up some photos!!
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Old 03-20-2011, 07:08 PM
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Re: 02 Overland

I'm not sure if the pistons can hit the valves. Some say they do and some say they don't. I also hope its just a valve train issue and not a dropped valve guide. But my recomendation is to start pull the cylinder head covers and see if there is something wrong there. Depending on the noise, it could also be an empty hydraulic valve lash adjuster, but unfortunately i also heard some stories about the dropped valve guides.
By the way, is the "check engine"light on and did you check for failure codes?
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Old 03-20-2011, 08:27 PM
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Re: 02 Overland

Quote:
Originally Posted by Frango100 View Post
I'm not sure if the pistons can hit the valves. Some say they do and some say they don't. I also hope its just a valve train issue and not a dropped valve guide. But my recomendation is to start pull the cylinder head covers and see if there is something wrong there. Depending on the noise, it could also be an empty hydraulic valve lash adjuster, but unfortunately i also heard some stories about the dropped valve guides.
By the way, is the "check engine"light on and did you check for failure codes?
Still on the trailer at the moment. The engine light was on when I started it up when I bought it. It ran for less than a min.

Haven't checked for codes yet.

I got to roll it in the garage and start diving into it. Any words of advice on the tear down? Any thing special I should know about?

Thanks again for the help.
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Old 03-20-2011, 08:36 PM
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Re: 02 Overland

Start reading the fault code(s). Just switch the ignition on/off 3 times and leave it in on after the third time. The fault codes will be shown in the odometer. It can already show you on which side to look at, when for example misfire is detected.
Is the sound a hard knocking or rattle?
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Old 03-20-2011, 08:45 PM
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Re: 02 Overland

Quote:
Originally Posted by Frango100 View Post
Start reading the fault code(s). Just switch the ignition on/off 3 times and leave it in on after the third time. The fault codes will be shown in the odometer. It can already show you on which side to look at, when for example misfire is detected.
Is the sound a hard knocking or rattle?
I am gonna go with a rattle. Like a lifter issue on other engines.

I will go through the codes tomorrow. As well as post up some pics if I can figure that out.

Thanks
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Old 03-24-2011, 05:58 PM
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Re: 02 Overland

Quote:
Originally Posted by Frango100 View Post
Start reading the fault code(s). Just switch the ignition on/off 3 times and leave it in on after the third time. The fault codes will be shown in the odometer. It can already show you on which side to look at, when for example misfire is detected.
Is the sound a hard knocking or rattle?
Been crazy busy. Wish I could have been working on the jeep.

The only code coming up is p0203.

Any idea's?

Thanks
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Old 03-24-2011, 06:16 PM
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Re: 02 Overland

The P0203 code tells that there is a problem in the cylinder #3injector cirquit. It can be the injector, but also wiring or PCM. You could try to swap the injector with an other position to see if the injector is the problem or not.
Lifter tick seems to be a more common problem on the 4.7. Could be one or more of the hydraulic lash adjusters.
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