[n20jeep]

ok i may have uped the shot of nitrous a lil to much....(found pieces of ring in oil pan and other random pieces of iron )....so i was wondering....has anyone here pulled there head off and how hard was it to do?....any hints on what parts i should remove and what order i should do them in?....

[silverxj2001]

try posting this on NAXJA in the "street and performance & other tech" forum.. .not many people i know here run nitrous, a bunch of guys there sure do though

sorry to bear about your problem

[n20jeep]

its not the nitrous that is my question.....its just the removle of the cylinder head i would like some advise on.....like say you were going to replace a head gasket or something along those lines....i just need to know so i can replace a piston and some rings

[XJ4oh]

How will you replace rings just from taking the head off? Piston will only reach top dead center..

[twisted_ed]

best thing u can do is make a call to the dealer and get the number to order a service manual, it will tell you how to rebuild that motor which is essentially what you need to do

[xjgrn]

Here's some more good news, you have to take out the crankshaft. That means from the bottom. thats besides the intake and exhaust, drainning the coolant Then with any luluck, you havent gouged the hell out of the cyl. wall. It might be cheaper to find another engine, than to do anything with that one.Lots of luck

[badron]

I would say you got a 500lb door stop. Rings or parts there of, just do not fall out. You got at least one blown piston. If she got more than 20k miles on her she needs to be bord out and a new piston fitted. (IMO)
Better off just getting a new motor.

R Robinson

P.S. Are you sure you over shot or did you lean out. Lean out is a common problem with new systems. I weak pump or a clogged filter will do fine putting around. But under high demand they may wimp out and let her go lean. Keep a close eye on your plugs. Plugs will tell you more about what going on inside the engine then a truck load of computers. A fuel presser gauge will let you know if the pump is keeping up to.

[n20jeep]

ok i know i ran lean .....and i know ive got a piston out ....but u guys are missing the main question....

...also u can pull a piston without pulling out the crank.....just pull off the head, the oil pan....then the rod caps....then push out the piston throught the top of the block.....next use a handheld hone(not sure of the tech name).....insert new piston with rings and push back down into the motor....its called a "inframe overhaul".....no need to pull motor or drop the crank

[cmotsvt]

Yeah you can do it without taking the crankshaft, but you cant do it RIGHT!

[twisted_ed]

i talked to my mechanic father, father in law and uncle in law, so out of 3 mechaincs they all said:

yes you can take it out the bottom without much dissassembly but getting a new piston in will be a problem

and you wont be able to tell if the cylinder walls are messed up

any if you do replace and anything in there is messed up such as valves and what not ull never know.

either full rebuild, replace or in my opinion if you have to bore and hone buggered up walls, STROKE it.

either way if you do it the easy and cheap way it will prob cost you mroe in the end cause of an additional full rebuild.

thats my research for the day.

[n20jeep]

twisted....i was actually planning on stroking it to a 4.7 soon....but the main point of this thread was not what i was going to do after i get the head off it was what was the best way to remove the head to atleast get a better look at the damage


....p.s. the valves would not be a problem....i have done a pretty good amount of head work in the past on other vehicles....so repairing broke valves and such would not be a big issue....would also be a good time to do a port an polish along with a full valve job ....and possibly upgrade to some roller rockers

[twisted_ed]

you're absoulutly right about the valves, i was under the impression you might replace a pisotn from the bottom in which case you wouldnt see or be able to replace a valve, i would think taking the head off would be the same with most motor, pull it, take off the manifold, valve cover and remove the head bolts. but then i havent taken the 4.0 apart yet. but i would think it would be fairly simple.. good luck

[artsound]

Originally Posted by n20jeep

ok i know i ran lean .....and i know ive got a piston out ....but u guys are missing the main question....

...also u can pull a piston without pulling out the crank.....just pull off the head, the oil pan....then the rod caps....then push out the piston throught the top of the block.....next use a handheld hone(not sure of the tech name).....insert new piston with rings and push back down into the motor....its called a "inframe overhaul".....no need to pull motor or drop the crank

Ok, you need to remove your serpentine belt-disconnect the fuel rails and wireing harness to the injectors-PS pump and bracket-then your intake and exhaust manifold--then the top bolts on your ac bracket(don't remove the bracket or ac just the bolts that aattach to the head) then the valve cover-rocker arms and bridges -pushrods
then remove the head(14 bolts and studds IIRC)-you will need to replace tyhe head gasket and get a manual and a torque wrench for proper reinstall bolt order and torque----2hours my guess-good luck

[n20jeep]

Originally Posted by artsound

Ok, you need to remove your serpentine belt-disconnect the fuel rails and wireing harness to the injectors-PS pump and bracket-then your intake and exhaust manifold--then the top bolts on your ac bracket(don't remove the bracket or ac just the bolts that aattach to the head) then the valve cover-rocker arms and bridges -pushrods
then remove the head(14 bolts and studds IIRC)-you will need to replace tyhe head gasket and get a manual and a torque wrench for proper reinstall bolt order and torque----2hours my guess-good luck

thanks.... i just needed a basic order of events....

[Dvs_Lance]

Didn't I just say not to long ago on another post that this was a bad idea???? Your jeep engine is just as easy to remove the cylinder head as a four banger. Only half the work of typical chevy or ford. Very easy, I would remove the intake first, exhaust second, then the valve cover. Helps keep all that nasty -=-=-=-= out of your valve train. If you are going to have the head rebuilt or replaced, you might want to remove the valve cover first, prob give just a tad more room. Make sure you buy a decent head kit for reinstallation, as the bolts used on the head of a 4.0 are what are known as "Torque to Yield". This means that they strech to a certain point to hold the head on well. They just don't need to be reused unless you have to. If I was going to pull mine, I would go ahead and order a kit from ARP, or another reputable after market performance company. That way you are going to get good bolts and believe me, if you ever have to pull it again, you dont want to break one! I would pick up a hayes manual or chilton manual for this if you have never done it. Its probably the one procedure that is explained as well as it should be. Good luck.

edit- here is a link that I use if I have any questions like yours. Its not exactly a repair manual, but it covers a lot.http://arrc.epnet.com/autoasp/index.asp?sid=2513715&uid=s9015408.main.autorefctr

edit - You will have to remove fuel lines and all the little stuff before you do anything else, i should have stated that above. I like using a roll of that blue masking tape to lable everything that I remove. It helps speed the process of putting it all back together


sorry about that link not staying in working order, Its something I have access to through the school, it seems after I post it, it only works for a little while.