So on to the head project! 0331... gotta change it... enough said. After doing my homework I decided on a brand new casting from Clearwater Cylinder Heads. It showed up about a week later and upon opening the top of the box I could see a beautiful and visibly thicker head with valves and springs installed. It took a couple weeks from there to get the time to install it but that went down last week. I'm not doing a write-up as there is plenty of info out there, and I also really appreciated this guy's video. In all it was a suprisingly easy job, just takes time, but I did encounter a few little unforeseen road blocks that I'll point out.
Let's start with the tools you'll want to have on hand. To get the party going you basically unbolt everything on and around the head, which took much longer than actually swapping the head. I read stories about the lower exhaust manifold bolts but personally I did not find them difficult to reach, but I've also got a full array of deep sockets (you'll need deep sockets) and extensions and u-joint/wobble/flex sockets. Getting them back on was just a little more tricky, but not too difficult. Some of the most valuable tools in my chest are ratcheting box end wrenches
. These things are fantastic and you would do well to own a set of four or five ranging from 10-15mm. Secondly, I love LOVE love my socket to drill adapters
. $3.85, are you kidding me? I crack a bolt loose then spin it off with my drill motor, saves enough time to make it worth it. The last special tool I had to buy leads me to my first unforeseen delay...
It wasn't until I actually mounted the new head that I noticed that the two studs for the exhaust manifold weren't included with the new head. They use a male torx bolt meaning you need a female torx socket, which I don't have and couldn't find anywhere. After striking out at numerous stores I happened to see these things out of the corner of my eye at Lowes, Kobalt's Xtreme Sockets
. They grip onto several types of bolts and worked like a charm on the exhaust studs. The next road block is that the intake manifold alignment dowels weren't included in the new head. I didn't pull the head all the way out of the box before mounting it (at 85 pounds it's not something I wanted to move around very much). You can't tap them out, they must be pulled, but I didn't want to risk deforming them with vice grips and didn't think that would work anyway. My local Jeep dealership said it would take nearly 2 weeks to get them in so that wasn't what I wanted to hear. I found some online but have ordered Jeep products online before only to get an email a few days later saying they were out of stock, so I wasn't going through that again. I ended up bringing the old head to our local machine shop in town and the guy had them out in 2 minutes for $5. He has a dowel puller that clamps onto the little thing then uses a slide hammer to pop them out. Perfect, we're back in business. Aside from that everything went very smoothly as far as installation goes. The only other thing I would recommend is to use a floor jack under the exhaust collector to get the manifold back into place.
Nothing special with these, but pictures are always fun!
This is one of the two exhaust studs I'm referring to.
Getting ready to break the head bolts loose. I used a highly specialized tool for this job, a thick pipe over my wrench.
Both the Haynes manual I used as well as the guy in the video I linked to (working on an XJ) mentioned the lack of room for the rear bolt, but there is enough space on the WJ to pull it out. Once again, WJ's triumph.
I was thrilled at the lack of crud and sludge (none, even at 185k) in the top of the old head.
Either call a buddy or just assume the position by sitting on the radiator support and give her a mighty heave ho. Thankful for the time I invest on the pullup bar. Not that bad actually, and yes, I'm proud of my self photography in setting the self timer on this one.
I wasn't as proud that I overlooked this ground and had to set the head back down, climb down from the front of the WJ to find the wrench, then shimmy back up there.
By the way, I had a scrap of plywood sitting over the battery with towels underneath to protect the fender, so the head went into my lap and then onto the plywood. From there I climbed down and pulled the head off the board and installation was reverse of removal with attention being paid to how I placed the head on the board so that I wouldn't have to rotate the cylinder head as it sat in my lap to get it ready to place on the block. Yes, the head really does weigh 85 lbs, but not a big deal.
While I was in there I went ahead and replaced the lifters. No special tool needed, just a telescoping magnet pen. Yet again I was thrilled at their condition as they didn't show any wear, and this is at 185K miles. New on the left, old on the right.
The new lifters I bought were branded Sealed Power by Federal Mogul. I was nervous about them being a littler shorter than the stockers, but after setting pushrods on top of them they were at the same height so that eased my fears. My pushrods also checked out to be straight after rolling them on a pane of glass.
After going this far you begin to pray that these lovely ladies don't crack their skirts, then start covering them up again.
Pretty new hardware in place, ready for pushrods/rocker arms/valve cover.
The conclusion? Well she runs strong... now! When I finished buttoning everything up and double checked everything I turned the key and she fired right up and was running very quiet as far as valve train was concerned but a bit rough as if missing a cylinder. No codes so I started unplugging injectors as I was concerned about a weak connection. It stumbled for every one except for #2 so I knew something was up there. By this point it was 1:30am and I was tired and frustrated so I called it a night.
Back up at 6am I installed new spark plugs and again she fired right up and was running perfectly smooth this time, but there was a terrible tapping noise! This is what I feared the most, that perhaps it was a mistake to pull those lifters and now I had a bad one. I let it warm a bit but the noise didn't subside and it would increase with (light) throttle. I cut it off and pulled the valve cover thinking maybe a lifter wasn't filling with oil and that a rocker must be dry. I cranked it with the valve cover off (which was pretty fascinating!) but thankfully it filled with oil just fine. I kept feeling around to locate the noise but couldn't find it! It was so loud it seemed like it had to be mechanical but after probing all around with a rod to my ear I realized it wasn't a mechanical sound. At that point I happened to see a blue flash and upon further inspection I realized I didn't have a good connection between my plug boot/coil rail and the #2 spark plug, so it was arcing between them and making a loud pop! I pulled the plug just to make sure it was ok and then made sure I had a good connection. I fired her off one more time and she was running just a smooth and quiet as ever!