AZJeff

The fact is that, for a motor mount to do it's job, it has to be compliant. That means the engine must be able to move (to some degree) independent of the chassis. Rubber is chosen for OEM because it achieves that goal best, but with a sacrifice in terms of longevity. Aftermarket "heavy duty" motor mounts wind up making the compliance component (the rubber/poly bushing) stiffer, and the steel parts more robust. The end result is a strong mount, but one that transmits more vibration. Using polyurethane aggravates that problem further, in that poly is not as compliant as rubber, and thus really makes vibrations get transmitted that much more. In summary, there is no free lunch here. If you want minimum vibes, stick with OEM construction. If you want stronger, there are plenty of choices, but ALL of them will transmit more vibrations into the chassis compared to OEM type.

It has been my experience that most of the leaks are going to be in one of three places: 1. the vacuum hose (and nipple) where the vacuum reservior is located 2. the vacuum hose where it travels under/near the battery tray 3. any of the in-iine vacuum hose fittings/"Tees" that head towards the manifold or the heater box Focus on those first, and then expand your inspection from there. Its not complicated, just tedious. Good luck.

A cracked valve cover won’t torque and seal correctly, and will continue to leak, even with a new gasket. getting a new metal valve cover is a good plan. I have an engine from a 2000XJ in my truck, and it uses a stamped steel cover with special grommets that prevent overtorquing the bolts and squishing the gasket too much. It’s pretty much leakproof with the new silicone gaskets.

Elaborate on what you mean by “cracks where the bolts go in” You mean cracks in the valve cover, I presume?

I would use helicoils. Having fasteners of multiple sizes attach the rocker cover would be annoying if it needs to be removed later. Fixing the screwed up holes will require drilling/tapping. Why not do it with Drill/tap that will allow the use of the standard fastener, which can be achieved via helicoil inserts. Those bolts are 1/4-20, by the way.

There is plenty of room UNDER the cab back behind the seats. It’s going to be a PITA to run vacuum lines back there, and then forward again, but it can be done. you will also need to protect it in some manner if you ever do serious off-road stuff. I would suggest locating it just inboard of the “frame” rail on the drivers side, and add a sort of skid plate attached to the “frame” to protect it.

Agreed......but if you explore IN DETAIL and document the wiring COMPLETELY, you can create your own wiring diagrams to keep it running correctly. it would be akin to making the wiring for a custom street rod. But you need to understand wiring, particularly MJ wiring, well to begin with.

Those brackets are useful if you install a larger/heavier front bumper, tow hooks or not.

And although there is an AC compressor, there are no refrigerant lines connected. (Although it seems to have an evaporator in the heater box.) Is there an condenser in the front of the radiator?

Follow up report: I ran the new lifters on the cam per recommendations given here, and the noise is GONE. The engine sounds like a normal 4.0, which isn't the quietest device in the world, but it no longer has that tick at startup, nor on a hot restart. I think I can declare victory. And thanks to all of you guys who offered suggestions and advice!!

I used fully synthetic Dex/Merc in the AW-4 on my 2000XJ and changed it every 25K miles. The vehicle used this stuff for over 100k miles, with no issues. My current MJ is using conventional Dex/Merc, and I just change it more often, due to the heat issues here in Phoenix.

If you are looking for decent, but not pricey, control arms, CORE 4x4 makes a set for the MJ/XJ starting at about $280.

Yeah, guys, I am up to speed on the torque pattern and the one lower-than-the-rest torque value. I also have the thread sealer needed. The FSM is useful here, for sure. All the head bolts are torqued per procedure, and all the valve train is in, slathered with plenty of “Redline” assembly lube. Tomorrow the valve cover, new spark plugs, and the coil rail go on. if the neighbor is available, I will enlist him to help me install the lower manifold bolts, since it’s impossible to see/feel them from above. Then install fuel rail/injectors, and P/S pump & belt, fill with fluids. Standby....

Gotcha. Makes sense. Got the new lifters installed after coating them with Redline assembly lube. Hopefully neighbor can help me lift head back on to block tomorrow. Then time to install new head bolts and torque them to the God-awful level spec’d in the shop manual!

So run it in at 2k for 20 mins steady. Roger that.

So I decided to bite the bullet and put in new lifters to accompany the (relatively) new pushrods, rocker arms, and rocker pivots that I installed when I put on the new Clearwater cylinder head about 5,000 miles ago. So here is my question: I will be using engine assembly lube on all the parts as put the engine back together. I will also be switching to Rotella 15w40 upon reassembly, and I will add some ZDDP supplement to the oil. But...do I need to do any special 'run-in' procedures with the new lifters on the old camshaft? Back in the day (when I was a young man), the recommendation was to run the engine at 2000rpm for something like 20 minutes to "run-in" the lifters to the camshaft. Is this crucial on the 4.0?

I have a tach in the machine. As far as cleaning lifters, since I have to remove the head to remove/replace a lifter, I would spring for a set of lifters. what other ideas would you suggest?

I am skeptical of the cam being trash, and here is why: I know that many guys feel the older flat tappet cams don't do well with modern oil, but I never had any issue with it on my two XJ's, both of which clocked over 100K on them. However, when I pulled the lifters to clean them when I put on the new head, they were RASTY. What I mean is they had varnish on them that was so bad, I had trouble removing a few with the lifter "slide hammer" gadget. After I got them out, they were just plain gunky on the top side, and I did my best to clean them with acetone, and then soak them in ATF before reinstalling them. The bottoms of the lifters where they ride on the cam were flat and smooth. It was obvious that they were still turning as desired, with no wear patterns showing. I almost think my "cleaning" of them may have actually made one or two of them MORE problematic, especially since I did not disassemble them in any way. In retrospect, I should have ignored the old adage about not putting new lifters on an old cam, and just replaced them all. This is me postulating (hoping?) that the issue of cruddy/semi-inoperative lifters is the source of my noise....

That is correct. When I start it cold, there is no tap. After a couple of minutes (no more than 5), the tapping begins. It "peaks" and remains constant until the engine is VERY warm (and you know what "warm" means in PHX.) Once the engine is really good and hot (temperature guage has been at 200-210* for more than 15-20 minutes, and idle oil pressure is now about 20 psi), then tapping sound is "almost" gone. If you listen CAREFULLY, you can hear it, but its no where NEAR as obvious as when in the "warm up" phase. Even my wife commented on the tapping in warm up phase, but she could no longer hear it on a hot engine (but I knew what to listen for, and detected it FAINTLY when hot).

I did not MEASURE them, but I inspected the ball ends for signs of wear, and saw none. When I stand them up on a hard surface, the heights are within 0.005" of each other, roughly. The pushrods I put in were new Melling ones, from Rock Auto.

I just finished taking out each pushrod, and blowing them with the air compressor. They are clear (which makes sense, since the pushrods were new when I installed the head 18 months ago.)

Clear? Meaning free of obstruction and/or not bent? Yes to both.

Well, I think I found the problem, or a least a major contributor: Intake pushrods on #4 and #6 aren't gettting hardly any oil up onto the rockers. I ran it for about 1 minute, and all the other rockers had plenty of oil accumulating in the low spots. Those other two were damned near dry (other than what had splashed around prior to the valve cover removal. I think a set of lifters are the order of the day, don't you?

Roger...standby

Cruiser, I just went out and ran each cylinder through TDC, and confirmed that the pushrods spin (and do not appear to be bent) when in that position on each cylinder. The pushrods were new when I put on the new head, so I don't "think" they could have gotten bent when I installed the new head and valve train. When I did the head, I thought "don't mess with the lifters, since they are run in on the cam" and the old adage was "don't swap lifters between lobes, or put new lifters on an old cam". (I realize this old adage is probably no longer applicable.) When i cleaned the lifters, I did so in acetone, and I will admit, they were somewhat varnish coated, and were tough to get out of their bores with the normal lifter removal tool. There was no scuffing or cupping on the bottoms of the lifters, and when peering down with a flashlight onto the lobes of the cam, I saw no signs of wiping on the cam (but of course, that wouldn't preclude lobe wear.) Whaddya think?