[B2CARPEN]

Hi my JF buddies!! It's been quite a while since I've been active on this forum due to some prior time restrictions, but now I finally have the time to document the current project that I've been sloooowly working on the past few months... very exciting :2thumbsup:

Background...
About two winters ago the 4.0L developed a loud knocking noise that I originally thought to be a collapsed lifter, so I decided to park the jeep in my garage until I found the time to tear into the engine. A few month ago I began disassembling the engine and removed the cylinder head to gain access to the lifters and investigated to see if any were heavily damaged enough to cause the symptomatic knocking noise. They were all collapsed, but not smashed or pancaked. This only meant that the issue was in the lower end and most likely a broken piston skirt (very common issue for high mileaged jeeps).

When i dropped the oil pan down for inspection this is what I found...



This means that I'm looking at a full engine rebuild at best, but from a positive point of view this gave me the excuse to ditch the AMC 242 crank and stroke the motor :devil: and that's exactly what this thread is about.

The motor has about 185k miles, but surprisingly there were not many unexpected challenges that have popped up so far, but I intend to share this entire process from start to finish and ongoing thereafter. This should be a lot of fun and I will do my best to document as much as possible along the way... picture heavy! :duhrock:

more to come soon...

 

[B2CARPEN]

Look who is back now...

Your jeep transformed into beast mode! Damn :drool:

 

[B2CARPEN]

Thanks Bud. Can't wait to see yours with a 4.7!

It's good to be back wrenching on the jeep again Mike, I'm excited as well.

 

[B2CARPEN]

Organization is key when tearing apart something you intend on putting back together again, so lable, bag, and separate out every bolt, wire, part you plan to reuse or reinstall. I took the precaution to organize everything since I was originally planning on rebuilding the 4.0L, but it doesn't hurt even tho nearly everything will be replaced.

Here's some pics of the engine tear down...

Valve cover removed, everything looked so clean considering the mileage...



Rocker arms and push rods removed...





Fuel rail removed, you can see how dirty these lil injectors are...







Spark plugs were shot...



Removed front of motor components (therm housing, water pump, fan clutch, move power steering pump to the side)



Wiring moved to the side and labled...

 

[B2CARPEN]

Some other things worth mentioning... remove the spark plug rail, alternator, A/C hard lines and compressor (if you happen to have A/C), disconnect all cables, wires, and vacuum lines from the intake manifold so you basically have left the manifold and headers to still be remove and then the cylinder head.

Don't forget to drain the coolant from the radiator and do your best to drain the heater hoses into a bucket or container, remove the radiator hoses. Drain the oil!! You do not want to drop that oil pan when it's filled with oil, you will be sorry.

 

[B2CARPEN]

Intake manifold removed, you can see the years worth of grime and carbon buildup ...

 

[B2CARPEN]

Next were the Exhaust headers.. (fyi - the bolts for the intake and exhaust were not as bad to get to as everyone makes them out to be, you just need a good set of socket extensions with a wobble ends, these will make your life so much better)

 

[B2CARPEN]

Then you can safely remove the cylinder head, which weighs 60lbs and is filthy and covered in oil (bad valve cover) and just plain sucky to lift off the block, just be careful and take your time. Once it's removed then you can remove the oil pan and gain access to the connecting rod bolts, you will slide the pistons straight up and out the top of the block.

So everyone who asks "can I remove the pistons without removing the head??" The correct answer is no. Even if u get it out after nicking up your crank journals, how do you plan to get new pistons installed? And if you have any real mileage on your engine (like mine) then you MUST take the block to a machine shop anyway... don't take short cuts here...

Pics of the cylinder head removed, removing lifters out from the lifter bores using an extended magnet, oil pan removed, in reverse order lol...

 

[B2CARPEN]

Well, look who is drinking some awesome sauce.

Subscribed.

Thank's brotha, good to have you on board! :cheers2:

 

[B2CARPEN]

Many more updates to come... have to head out to the machine shop now. I will report back soon.

 

[B2CARPEN]

Holy ****, he lives.

Lol yes indeed and my jeep will live again soon too

 

[B2CARPEN]

Here's the culprit, piston #6

 

[B2CARPEN]

The block and head are now in good hands at Speed Performance CNC machine shop in Wauconda IL, Tony is an amazing guy who has been in the machining and engine building business for 25+ years and knows his ****. Not only will this engine be machined to perfection, but it will also look badass once I rebuild it, paint it and drop it back into a clean and painted engine bay.

 

[B2CARPEN]

I will get back to posting more of the tear down pics shortly

 

[B2CARPEN]

Here's pics of the combustion chambers and valve seats of the head after being degreased then power washed. It will even look better after a good port and polish and bead blast. I'm still figuring out what cam, valves, and springs I'm going to run, but not worried about that quite yet...

 

[B2CARPEN]

It was this point that I decided to pull the block and go the stroker route. If you are just rebuilding your 4.0L or going nuts building a torque monster stroker you should ALWAYS send your block, head, connecting rods and pistons, crank, and anything else associated with your build to a machine shop for proper inspection, cleaning, machining, and balancing.

The tolerances are within thousands of inches which take special tools and gauges to figure out, so taking your engine and components to a machine shop is a must! It is money well spent and foolish to skip this step. Just my two cents.

Here's the jeep with the front grill removed to make life so much better when removing the block from the trans...

Engine hoist in position and attached to 4 head bolts on each corner of the deck...

 

[B2CARPEN]

Removed all the bolts attached from the trans (NV).. there are 4 of those bolts connected to the engine and the top two are E12 6 point star bolts and a complete ***** to remove. I ended up removing the motor mounts first so I could lower the block and trans to gain better access to those two upper bolts. After stripping the daylights out of them, I went for a different approach lol..

With the heads of those bolts cut off, the rest threaded out by hand. Then the block carefully was pulled apart from the trans. I used a ratchet strap around the frame rails under the trans to support it while the block was out.

 

[B2CARPEN]

Setting up the engine stand and getting it into position, removed the clutch, pressure plate, and fly wheel while hanging from the hoist. You have to try and torque the bolts off the fly wheel while preventing the crank from spinning and the block from swinging around.. fun times.

 

[B2CARPEN]

Looks like my past weekend with a L-226.

Anyway good to see you back after lurking for what seems like eons!

Lol funny that you noticed I have been lurking and seldomly posting here and there.. It is good to be back writing my own posts with some progress. This stroker build is by far my favorite mod to date

 

[B2CARPEN]

This is looking awesome man!

I agree! Thank you! Just wait till you see some of the goodies that are waiting to be installed