The dreaded symptoms

[bromel]

I understand it is extremely tough to place a 4.0 out of a grand Cherokee in a TJ but can the head be used? I have access to an engine out of a Cherokee and knowing my luck (now that I have talked about it) my 2001 head will break tomorrow. I would recon this head for insurance. thanks

Yes, but I would only use a 0331 head from a 2003 or 2004 Grand Cherokee. (Maybe 2002, though I think the WJ used the bad casting for an extra year.)

Make sure the head is stamped TUPY as that signifies the updated casting.

Also, my understanding is that WJ and 2000+ TJ blocks are interchangeable and can freely swap.

 

[williambmac]

I understand it is extremely tough to place a 4.0 out of a grand Cherokee in a TJ but can the head be used? I have access to an engine out of a Cherokee and knowing my luck (now that I have talked about it) my 2001 head will break tomorrow. I would recon this head for insurance. thanks

You re incorrect. the 2000-04 wj motor is a direct swap for a tj. The xj 4.0 is different.

 

[sam53]

Hey, great, thanks!

 

[jeepguy03]

You re incorrect. the 2000-04 wj motor is a direct swap for a tj. The xj 4.0 is different.

Not quite. It depends what year. The later model TJs with the alternator up top were the same blocks as a WJ 4.0L, the earlier TJs (97-99) were the same block as an XJ/ZJ.

 

[williambmac]

Not quite. It depends what year. The later model TJs with the alternator up top were the same blocks as a WJ 4.0L, the earlier TJs (97-99) were the same block as an XJ/ZJ.

I'm talking 2000 and up tj's

 

[onoffroad]

"I used vice grips to set the small knob to 110 ft-lbs and it didn't move on it's own when I was tightening." Doesn't sound right. But maybe I'm not reading it right . I would never tighten the adjustments on a calibrated tool like this.

 

[jeepguy03]

"I used vice grips to set the small knob to 110 ft-lbs and it didn't move on it's own when I was tightening." Doesn't sound right. But maybe I'm not reading it right . I would never tighten the adjustments on a calibrated tool like this.

+1

What kind of torque wrench is this?

 

[TJFett01]

+1

What kind of torque wrench is this?

I have a 1/2" Tekton. P/n: 24340

"I used vice grips to set the small knob to 110 ft-lbs and it didn't move on it's own when I was tightening." Doesn't sound right. But maybe I'm not reading it right . I would never tighten the adjustments on a calibrated tool like this.

I was referring to the locking nut on the bottom of the handle as the small knob. Sorry for any confusion, hopefully I am able to clarify.

I loosened the locking nut, turned the main handle by hand to 110 ft-lbs, hand tightened the locking nut and used vice grips to snug the locking nut (barely a quarter turn). Double checked to make sure the locking nut wasn't loose or the handle (for setting ft-lbs) didn't move to a different number.

After #13 bolt snapped, I looked at the torque wrench and it was still at 110 ft-lbs.

At some point this week I will check calibration to see if my torque wrench is or isn't in spec.

 

[TJFett01]

Update:

Waiting on new ARP head bolts, engine pan support, Mopar timing chain, camshaft gear, and crankshaft gear. I'm changing the timing parts because I have a feeling I'll kick myself later for not doing it.

Been cleaning the block, oil pan, and valve cover in the meantime.

A few questions:

Does anyone know what head bolt chaser size to use on the engine block?

My timing cover has no external damper timing mark that I can see. Do all 4.0 timing covers have this or did mine get removed/ broken off? Is this a different style to determine TDC?

On the inside of my timing cover there seems to be strange cracks, does anyone know what could have caused that? The rubbing block inside had a broken tab.

 

[TJFett01]

Bump

 

[JKP]

Looks like it was broken off.

 

[JKP]

https://www.carparts.com/details/Je...fmu_IkzoZl8oc3KhpF8aAg_HEALw_wcB&gclsrc=aw.ds

 

[jeepguy03]

The "cracks" aren't actually cracks they are just imperfections in the casting and shouldn't hurt anything. That is really strange that the timing piece is missing. Maybe it was damaged when someone attempted to replace a harmonic balancer?

 

[TJFett01]

Looks like it was broken off.

I think you’re right.

The "cracks" aren't actually cracks they are just imperfections in the casting and shouldn't hurt anything. That is really strange that the timing piece is missing. Maybe it was damaged when someone attempted to replace a harmonic balancer?

Awesome. Glad its an imperfection and not damaged. If someone did work under the timing cover, that would explain why I was missing a bolt (red arrow in pic) which was buried under 1/2" of sluge/road grime (green arrow).


Should I get a new timing cover or just roll with what I have?

 

[JKP]

After thinking about it, I think this is your TDC pointer that you would line up with the mark on the damper:

There should be a rubber snubber between those tabs on the inside.

 

[jeepguy03]

I think you’re right.


Awesome. Glad its an imperfection and not damaged. If someone did work under the timing cover, that would explain why I was missing a bolt (red arrow in pic) which was buried under 1/2" of sluge/road grime (green arrow).


Should I get a new timing cover or just roll with what I have?

View attachment 225015

Jeez, it looks like someone was messing around on that thing, and holy grease! I mean if the cover is otherwise fine you can replace the chain and just line up the timing marks before disassembly/re-assembling it. Plus you can make sure you are at TDC since you have the cylinder head off. Does the damper look like someone was prying on it? That's the only thing I can think of as to why that would break off.

 

[TJFett01]

After thinking about it, I think this is your TDC pointer that you would line up with the mark on the damper:
View attachment 225030

There should be a rubber snubber between those tabs on the inside.

I placed my timing cover back on and the harmonic balancer (not all the way on). After checking my index points on my gears, it seems like that point is for TDC. I learn something new everyday.

Are the numbers on the cover there to indicate how warn the chain is?

Do you have a picture the rubber snubber? Do you mean the rubber tensioner inside the cover?

Jeez, it looks like someone was messing around on that thing, and holy grease! I mean if the cover is otherwise fine you can replace the chain and just line up the timing marks before disassembly/re-assembling it. Plus you can make sure you are at TDC since you have the cylinder head off. Does the damper look like someone was prying on it? That's the only thing I can think of as to why that would break off.

The front and driver side of the engine block is caked in about 3/8" of grease. Since I have the intake and exhaust manifolds out of the way I can actually do some cleaning.

I'll have to find the damper since it vanished into thin air. It broke right where the tab began. I ordered a new one.

 

[JKP]

Yeah, some call it a tensioner, Mopar calls it a snubber:

The numbers are there for the old 4.0s with a distributor so that the timing could be set.

My '92 has them, even though the distributor on it is not adjustable. But you can see how much advance it is running with a timing light.

 

[TJFett01]

Yeah, some call it a tensioner, Mopar calls it a snubber:
View attachment 225197


The numbers are there for the old 4.0s with a distributor so that the timing could be set.

My '92 has them, even though the distributor on it is not adjustable. But you can see how much advance it is running with a timing light.

Ahh okay, thanks for clarifying!

 

[TJFett01]

Update and some good news!

Since my previous post, I was waiting for my timing chain and gears and my schedule to line up with my buddy to finish the work.

The parts were delayed a few days because of a snow storm in Ohio. Got the parts in and they are much tighter than the original chain. Glad I decided to get new timing pieces so that I won't have to worry about it.

We put everything together, topped off the fluids and started it up. After 30 seconds of running on the first startup, the thermostat gasket leaked coolant onto the belt and sprayed the driver side. After replacing the gasket it was smooth sailing.

For the second startup, the jeep ran a little rough for the first 2-3 minutes (it sat for almost a month waiting for parts) but smoothed out afterwards. There was white smoke upon start up however it went away after a few minutes and hasn't returned.

The engine sounds great, just as it did before it overheated. Might I dare say slightly better than before! No weird nosies to report.

Been driving for a week and checking my fluids after every trip. No leaks detected, no oil/coolant contamination evident, and no temperature issues going 100 miles strong!

The only issue I had was my bank 2 sensor 2 tripping the CEL for P0158 and P0161. It was a Bosch sensor that has been there for years without issues, but I believe it might have been damaged when the exhaust was removed (as we left them in, just unplugged them). A new NTK seems to have fixed the problem after 25 miles.

Within the next few days, I'm going to finish a writeup of what exactly I did with this repair/ rebuild. Provid part numbers for reference and my thoughts on the whole process.

Stay tuned!