TrollHammer

Finally decided that 300,500 miles was enough on my wife's GC, so we traded it for one with lower miles, around 150k. We were told it might have a blown head gasket.

Tinkered with it a little, hoping that plugs and wires and a water pump gasket would fix it, but indeed it appears the head gasket is bad, and it appears that the oil isnt draining on one head, looks like quite a bit of build up.

We decided to start over from new on it and Im going to rebuild it.

It is a 93 grand cherokee limited with a V8. i have had experience working with the old one, but not a complete rebuild, and Im sure Im going to have questions. Already do:

What place has the best deal on a rebuild kit?

Would it be easier to pull the engine with the trans attached or detach the trans in the vehicle?

What issues have others found in pulling/ rebuilding the V8? Anything odd Im going to run into?

Bustedback

In this day and age it is more cost effective to buy a reman long block, less time consuming too.

jronald

If you have the time, rebuilding the engine could be very rewarding. That said IF you have the time.
As the 93 was a slightly EPA'ed version of the classic Dodge 318, there are tons of kits and easy upgrades that the engine will respond to. Porting and polishing the intake and exhaust are easy to do if semi-time consuming. 3 angle valve jobs, matching gaskets and may other old school ideas. Careful assembly is worth an easy 25 horses over stock. Here are a few ideas: http://eddiesvalvegrinding.com/dodge...nce-engine.htm . Do a bit of research before you start and incorporate as you go. Work on air flow and liquid flow. DO NOT use a High Volume pump. Its not needed with a properly set up engine.
In no particular order:
Port match the gaskets, intake and exhaust ports (airflow)
Clean the inside of the block of casting flash (oil drain back)
Touch up the piston rod beams of flash (oil drain back)
Port match the oil drainback holes in the heads
Polish the pocket around the valves
3 angle valve job
Pick a cam company and work with them on springs and duration
Shim the spring on a stock pump (dont use HV pumps)
Make 100% sure your bottom end has the right clearance.

Ron

Jordan1996 ZJ

when you say "port" the intake and exaust manifolds how would you do that? a pencil grinder? I am rebuilding mine and i have all the time in the world

and whats a 3 angle valve job?

jronald

3 angle
http://www.vadriven.com/forums/showthread.php?t=112972

Port and Polish
http://www.ehow.com/how_4928270_port...der-heads.html

Basically, its all about air flow. For street cars at the Hot Rod shop we would always buy several different brands on Intake Manifold Gaskets, and who ever had the biggest ports, we ground to match them.

Hey one other idea I thought about:
Attach a vacuum source to the "EMPTY" engine once assembled then with an auto stethoscope apply sealer to all the areas that hiss. You will end all you oil leaks. I had a Chevy that t 125k, all you needed after you worked on that engine was a single paper towel!

Ron

jronald

Heres a decent Small Block Chevy description of Port and Polish.
http://www.ehow.com/how_7663863_port...sbc-heads.html

Ron

celicoupe

If it needs head gaskets then it overheated. Make sure you don't have small cracks between your valves. The Magnums are notorious for that. I replaced mine with "Iron Ram" heads from Hughes Engines. They have pressed in valve seats which are way better than the stockers. They flow better too.

jronald

celi, I don't understand your comment. Anytime you remove the head, it needs head gaskets.

Ron

taythegibs

Right, you would have to put in new ones for a rebuild, but as he is saying if the reason for tearing into your engine is because of head gaskets then there is a chance that there could be trouble with the heads.

TrollHammer

Good points, thanks everyone! I never new what caused head gaskets to fail, the only one that ever failed on me did multiple times, and had the valve guide cracking you mentioned, but never noticed it overheating prior to that. It was a LeBaron and the computer blew right after the second head gasket, so perhaps it wasnt seeing the temp right (digital bar grapg displays)

Anyway, it sounds like some things to think about and Ill look into those links when I get to a regular computer (phone right now).

We had swapped the GC origionally because that one wasnt worth rebuilding, the whole jeep had small minor issues that added up to low overall value. This one is clean except for.the engine, and I was told a rebuild kit could be had for much less than a replacemrnt. im still looking for a cheap drop in, obviously, but they are rare in these parts. The only one I saw was snapped up before I even saw the listing.

I need the experience anyway. Eventually Id like to build up a stroker, but have only done theory and small engines so far. Figure rebuilding stock or near stock would be better to learn on.

How much time, in hours, would you say a rebuild takes? I have set aside a week this month to pull it and tear into it, and a week next month to hopefully put it all back together. I also have two former mechanics in the family that can help me on some of the more difficult parts.

Doesnt sound like some of these upgrades would be much expense or effort, versus boring cylenders and buying crank shafts. What other.vehicles was this engine used in, what years, and is that dodge engine its predicessor like the 4.2 was to the 4.0? Most of my experience.in research is with the 4.0.

Would those heads mentioned be stronger than stock, or do they just have better guides?

Should mention that this will still be a pavement pounder for my wife. She might do some green dot trails now and then but generally just a backup daily driver for both of us. I have some plans for my current DD that will take it off line for a week, so this one needs up and running first.

freegdr

agreed plus you get a warranty

jronald

Rule of thumb is 30 hours:
10 hours in and out
10 hours machine
10 hours dis and then reassembly.

That said, it does not sound like that's what you are planning.
If you are talking no machine work, do some research on the following subjects: File to fit piston rings and 1 thousand over bearings, rod and mains. I have seen some PicNic table rebuilds do perfectly fine for 100,000 miles. That will give you plenty of miles and years to add.

Ron

celicoupe

The iron ram heads aren't really stronger but they wont crack between the valves because the valve seats are a better design. They are fairly pricey though. hughesengines.com

TrollHammer

Looking at rebuild kits vs a drive for a donor vehicle, im now thinking of just poppong the heads off and seeing what they look like. I didnt get a brace up to pull the engine, and the lower block is a little intimidating at the moment.

Is there a trick to the dreaded passenger side exhaust coupling? Getting the bolts out isnt a big deal, but the upper one is a pain to get back in. Can I just leave the pipes attached and lift the heads out leaving the manifold in there or do I have to deal with that stupid bolt?

Any other thoughs on heads?

Looking at remanufactured engines, i dont see the cost benifit in getting one. 1500 bucks for a jeep that bluebooks at 2k doesnt line up.

Well, Ill know more about the condition of the engine when I pop the heads. Itll take me a while to get everything cleared off the top before gettting to the exhaust.

TrollHammer

Wow, they are dumb at the parts store. Cant tell me anything for the size of the end shaft socket or fuel line disconnect tool, just "bring it in or use something to get the size". If I had something that size I wouldnt need the tool.

$80 to rent a set of sockets to save... Possibly no gas?. Grrr.

Oh well, good excuse to buy tools.

Anyone kniw what size the vib dampener bolt (or whatever the bolt is on the end of the engine with the pulley) is?