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Empty_Pockets 07-15-2013 09:41 PM

WJ noob looking for some tech info
 
Dont kill me its probably a dumb question but im new to WJ's and 4.7L's. I found a gorgeous 03 WJ overland that im going to look at tomorrow. It dropped some valves, I was thinking of swapping a 5.3L chevy in it but the swap is way over my head after seeing a few swap threads. Will a dodge ram 4.7L work in the wj? Is there a way to fix the valve issues that they 4.7's have? How is the 4.7 on fuel?
Im switching for an xj to this truck they are alot different, any tips as to what to look for on these trucks would be helpful as well.
:cheers:

cubalz 07-16-2013 07:04 AM

I would just repair the engine that is in it. Replace the heads but make sure that the piston is not damaged where the valves dropped. Why make it super hard on yourself but fixing a head issue by doing some sort of swap? As far as fuel mileage? I get roughly the same mpg with my GC with the 4.7 as I do with my Rubicon with a 4.0 running 35's. Both suck but no one buys a Jeep for its stellar mpg's (GC CRD's excluded ;))

Make sure that your offer for the Overland takes into account the outlay of cash to fix the known issue and any others that may rear their ugly head after you get it running and driving. Good Luck

Empty_Pockets 07-16-2013 08:52 AM

Im just looking for something thats gonna be somewhat decent on gas. My Camaro with a cammed 6.0 gets about 9mpg around town and doenst see weather. As for the motor I was thinking about swapping engines just for piece of mind, what if the piston has a tiny crack I cant see or a broken ring land or something.

cubalz 07-16-2013 09:03 AM

You wont know until you dig into it and pull the heads. A scored piston top is not a deal breaker by any means as far as reusing/repairing the original engine.

Empty_Pockets 07-16-2013 09:14 AM

Ill have to look into what the parts are going to cost for either. Ill be doing all the work so labor isnt an issue.

Jeeples 07-16-2013 10:18 AM

Quote:

Originally Posted by Empty_Pockets (Post 15681112)
Dont kill me its probably a dumb question but im new to WJ's and 4.7L's. I found a gorgeous 03 WJ overland that im going to look at tomorrow. It dropped some valves, I was thinking of swapping a 5.3L chevy in it but the swap is way over my head after seeing a few swap threads. Will a dodge ram 4.7L work in the wj? Is there a way to fix the valve issues that they 4.7's have? How is the 4.7 on fuel?
Im switching for an xj to this truck they are alot different, any tips as to what to look for on these trucks would be helpful as well.
:cheers:

IIRC, the Dodge 4.7 has the starter mounted on the driver's side of the engine which won't work with the WJ's transmission.

As for preventing the valve seats from dropping, it's the same as any other aluminum headed motor:

Don't allow the engine to overheat, follow recommended cooling system maintenance intervals and use the proper coolant. You have a hardened steel valve seat pressed into a soft aluminum head. They already expand and contract at differing rates, but once you overheat the motor you can cause stress cracks around the seat in the head or weaken the press fit on the seat.

Quote:

Originally Posted by Empty_Pockets (Post 15682368)
Im just looking for something thats gonna be somewhat decent on gas. My Camaro with a cammed 6.0 gets about 9mpg around town and doenst see weather. As for the motor I was thinking about swapping engines just for piece of mind, what if the piston has a tiny crack I cant see or a broken ring land or something.

Go buy a Cobalt or a Neon if you're wanting to save a noticeable amount in fuel for a DD. Realistically you'll get 16, maybe 17 MPG driving like a grandma in mixed city/freeway driving conditions with a WJ.

Double E 07-16-2013 10:31 AM

+1. The 4.7 will return 21MPG if driven on the highway with fresh fluids and all maintenance done (TB & IAC clean, plugs & fuel filter).

17 is the best you'll do around town and that's driving like grandma.

If you buy it, do not crank it. Pull the heads & see what you have. There are a LOT of pics on this forum that show the droped valve seat issue and you'll see why you do not want to crank it.

Keep in mind that it also probably overheated at some point so there's a second, underlying problem. Still not a big deal to fix though.

Hope you can pick it up for $1000 or less and after putting 2K into heads, gaskets, new piston(s), etc. you should have a $7000 dollar vehicle to sell for something that gives you cargo room, some off-road capability, economy and reliability.

Or keep it and try to keep the MPG above 16. You'd have a great platform to upgrade with a solid front axle that you've been through yourself and know it's good for 150K miles.

Empty_Pockets 07-16-2013 10:42 AM

Quote:

Originally Posted by Jeeples (Post 15682653)
IIRC, the Dodge 4.7 has the starter mounted on the driver's side of the engine which won't work with the WJ's transmission.

As for preventing the valve seats from dropping, it's the same as any other aluminum headed motor:

Don't allow the engine to overheat, follow recommended cooling system maintenance intervals and use the proper coolant. You have a hardened steel valve seat pressed into a soft aluminum head. They already expand and contract at differing rates, but once you overheat the motor you can cause stress cracks around the seat in the head or weaken the press fit on the seat.



Go buy a Cobalt or a Neon if you're wanting to save a noticeable amount in fuel for a DD. Realistically you'll get 16, maybe 17 MPG driving like a grandma in mixed city/freeway driving conditions with a WJ.

No need to be a ****** dude. I was just asking. What I consider decent gas mileage is about that anyways I daily drove my Camaro for years and my current daily is an xj so I wasn't expecting it to get 25-30 mpg.

Empty_Pockets 07-16-2013 10:46 AM

Quote:

Originally Posted by Double E (Post 15682705)
+1. The 4.7 will return 21MPG if driven on the highway with fresh fluids and all maintenance done (TB & IAC clean, plugs & fuel filter).

17 is the best you'll do around town and that's driving like grandma.

If you buy it, do not crank it. Pull the heads & see what you have. There are a LOT of pics on this forum that show the droped valve seat issue and you'll see why you do not want to crank it.

Keep in mind that it also probably overheated at some point so there's a second, underlying problem. Still not a big deal to fix though.

Hope you can pick it up for $1000 or less and after putting 2K into heads, gaskets, new piston(s), etc. you should have a $7000 dollar vehicle to sell for something that gives you cargo room, some off-road capability, economy and reliability.

Or keep it and try to keep the MPG above 16. You'd have a great platform to upgrade with a solid front axle that you've been through yourself and know it's good for 150K miles.

I'll have to see if there are titanium seats avaliable I've had good luck with them in ls engines. Thanks for the advice. Any other problems With the WJ's other then blend doors to look out for?

rdkendrick 07-16-2013 11:10 AM

"No need to be a ****** dude. I was just asking. What I consider decent gas mileage is about that anyways I daily drove my Camaro for years and my current daily is an xj so I wasn't expecting it to get 25-30 mpg."

Lighten up, Francis. These people are only trying to help you. If you cannot say something nice, don't say anything at all. As the saying goes, you catch more flies with honey, than you do with vinegar.
Good luck in whatever you decide to do.

Sent from my iPad using Forum Runner

Jeeples 07-16-2013 11:26 AM

Quote:

Originally Posted by Empty_Pockets (Post 15682749)
No need to be a ****** dude. I was just asking. What I consider decent gas mileage is about that anyways I daily drove my Camaro for years and my current daily is an xj so I wasn't expecting it to get 25-30 mpg.

I fail to see how I was being an *******? You asked several questions and I answered them all with factual information that can readily be found here on this forum. I even had another senior member (Double E) back me up on my response. But you're right, a marginal increase in fuel economy easily justifies a second car payment, insurance, mods (because let's face it, that Jeep won't be stock for long), and the money spent to get the WJ running. It should only take 15 years of use for that WJ to pay for itself, assuming you never DD your F-Body again.

If I was going to be an *******, I would have :laugh: at your silly 11 second 4th Gen F-body getting 9 MPG. Then I would have went on about how I could take my crappy Neon, spend about $2k for an upgraded fuel system and big turbo kit then easily get into the 11's. All while still get 20+ MPG driving around town and closer to 30 MPG on the freeway at half the cost of your Camaro.

That better? :kiss:

alfaitalia 07-16-2013 11:48 AM

Now, now....play nicely children!:thumbsup:

Jeeples 07-16-2013 11:59 AM

Quote:

Originally Posted by alfaitalia (Post 15683003)
Now, now....play nicely children!:thumbsup:

The last half of my previous post was purely hypothetical :D

Regardless, there are much better choices out there for a fuel friendly DD. However, buying a WJ, particularly a 4.7, with a blown engine can be a bit risky if you're planning on rebuilding the existing engine. It would be much better idea to just replace it with a rebuilt long block and save money on repairs elsewhere.

Empty_Pockets 07-16-2013 12:41 PM

Quote:

Originally Posted by Jeeples (Post 15683053)
The last half of my previous post was purely hypothetical :D

Regardless, there are much better choices out there for a fuel friendly DD. However, buying a WJ, particularly a 4.7, with a blown engine can be a bit risky if you're planning on rebuilding the existing engine. It would be much better idea to just replace it with a rebuilt long block and save money on repairs elsewhere.

I was not planning on just doing a top end, I was looking at replacing the engine. I would not trust a piston that made contact with a valve, that just me. I wouldnt want to do all that work to find out that the piston was damaged and I couldnt tell or was weakened. Ive learned that lesson lol. I would rather spend alittle more time and money to do the repair once then twice the amount of time and money to do it twice. I was just wondering if it would be on par with my xj on 33 which is seems it will be.

rdkendrick 07-16-2013 12:58 PM

Quote:

Originally Posted by Empty_Pockets (Post 15683255)

I was not planning on just doing a top end, I was looking at replacing the engine. I would not trust a piston that made contact with a valve, that just me. I wouldnt want to do all that work to find out that the piston was damaged and I couldnt tell or was weakened. Ive learned that lesson lol. I would rather spend alittle more time and money to do the repair once then twice the amount of time and money to do it twice. I was just wondering if it would be on par with my xj on 33 which is seems it will be.

Well, the Overland has a 4.7 HO, is that what you were planning on putting back into it? It's a good, strong engine. You might want to take a look at 65Mustang's re-build thread, or MikeBeans thread:
http://www.jeepforum.com/forum/showt...errerid=432347
that shows where his valve did hit a piston and he just changed the head.

Sent from my iPad using Forum Runner


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