tore down the motor today
 

And was amazed by how much sludge is in there! No wonder the darn thing blew up. I'm sure there were plugged oil passages that led to the rod leaving the block. Now that I've got the head off I noticed a broken valve spring as well which will have to be fixed. My question is, does anyone know the differences between a 94 grand cherokee head and a 99 cherokee sport head? I'm putting the 94 grand cherokee motor in my 99 cherokee sport and am wondering if it is really necessary to swap the heads, especially now that I found a broken valve spring? Also, if I do have to swap the heads, can I use one of the valve springs out of the 94 head or are they different? :brickwall:

http://i78.photobucket.com/albums/j1...1/30fbf642.jpg

http://i78.photobucket.com/albums/j1...1/537d16f3.jpg

http://i78.photobucket.com/albums/j1...1/8bc64e02.jpg

http://i78.photobucket.com/albums/j1...1/fe62be15.jpg

omfg

Yes indeed :no:

I swear I bought it that way, I change my oil regularly :icon_cheesygrin:

ive seen worse but not on this new of a vechicle,was the oil pan full of crap also

I didn't even pull it yet, kinda figured there was no point since it's junk anyway but I am kind of curious as to what it looks like in there. Maybe I'll go pull it after lunch and see. I need to figure out what I'm gonna do for a head though. I don't have the tools to do the valve spring so it would be really nice if I could use the 94 head. :whistling2:

do some research on the part number between the years if there the same you can use it for ther head and the spring you can rent the valve spring tool at auto zone when you return it they give you all the money back

Went ahead and pulled the pan to check it out. I think that will buff out. :dunno:

http://i78.photobucket.com/albums/j1...1/6b71c09b.jpg

http://i78.photobucket.com/albums/j1...1/ce7d9753.jpg

http://i78.photobucket.com/albums/j1...1/c57e80bd.jpg

thats just fing crazy dirty

and crazy destruction

thanks for the pics!

My dad is a tv repairman, he has an awesome set of tools! We can fix it!


But seriously, Ouch and ouch again,

motor time.


ouch.

cpnwrench:nuke::pinch::nuke:

Well I went out and started comparing the two motors and I think I'm gonna try to run the 94 motor with the 94 head. I swapped over all of the accessories and sensors and the intake and exhaust manifolds and everything seems to bolt right up. I also swapped out the flexplate since the converter bolt pattern was different and also because I'm betting the cps needs to see the same ring. Anyway, looks like it all should work from the outside so I'm gonna run with it. :dunno:

What #cylinder was that?

As far as the baked on crud in the oil pan, I've found that a can of oven cleaner will work wonders. I use the cheap stuff, too.

Sorry about your block! But I doubt it was your maintenance. Did you find any of the old con rod bearing? If there's no obvious damage due to lack of oil, then probably the rod bolt failed before anything else.

You know, you've asked a question I've been trying to get a straight answer for and I dont' think you'll find it on the forums because we really need to ask an engine builder.

The difference between these two years is the cam. The grinds are completly different, and Chrysler did this because of emmissions and power. I'm told the 97+ dual pattern cam is desired both for more power and to allow the engine to run properly with the newer computer/emmissions. I don't know what's going to happen if you use the complete block unchanged from the '94- maybe nothing, or maybe it might run even better, who knows.

In my case I want to run a older block (with a single pattern cam) with a newer head and I'm not sure what rockers and lifters to use, the old ones or the new ones, and wether I should install a dual pattern cam. Wish I could find a professional Jeep engine builder who knew what they were talking about.

Well I might not be able to answer all you questions but I can tell you this:

1. The complete 94 motor will bolt right in. I had to change every single external part on it though. Motor mounts, flex plate, all the accessories, sensor etc. all had to be swapped out.

2. It runs great! :thumbup: I got it all put together today and it fired right up. I drove it around a bit and it is running great, has plenty of power and so far no check engine lights or anything.


As far as putting the newer head on the older block I'm not really sure. I know the newer head has dowels that the old one doesn't and different valve springs etc. so I don't really know if it would work right with the older cam or not.

I'm just extremely happy that the older motor seems to work great with my computer and everything and has no CEL. Power output seems to be pretty darn good too. :batman: