Biggest mistake you can make, if you don't want to do it over, is not getting exactly the OE head gasket. .045 thick. ( As opposed to the heavier .055", unless you set the lifter preload. It will throw the lifter lash off, WAY off, and you will (somewhat silently) pound your lifters and cam until one breaks and starves the others for oil. ) So, if you're not going to set up the lifter preload, with new or old lifters, at least use the OE gasket that way you stand a chance of not getting it wrong. But with a new head you should really be setting preload. But if you dont at least use the OE thickness gasket. this is more important than anything else you can do outside of putting it together wrong.
REMEMBER, only a high idle when you start it up, until the lifters are all oiling,. crank the starter with the coil disconnected first to pump them up somewhat.
And use lots of cam lube! Always good advice.

 

Head came in last night! This past week was a bit of a bust due to my illnesses, and we are a bit behind on the block cleaning. We're hoping to tackle it today. Exhaust manifold bolts are in the old head but look like they're in good shape, so we're going to try and pull them. We have to check the block and new head to see what is/isn't there are far as pins. So that might be another thing we have to order and wait for. My partner picked forcep-things to pluck things out of that cavity, the shop vac is ready to go, and today is going to be an official clean-the-f*$&-out-of-the-block day. Thanks again all - I'll likely post an update with photos later today.

 

*rolls eyes*

 

Not sure why you’re rolling your eyes at me, but whatever. Sorry I’m excited about pulling apart my first motor and getting advice on how to go about it ¯\_(ツ)_/¯

So while cleaning up the block we saw some marking on cylinder 5. It still feels smooth and not pitted or anything but does anyone know what this is and if we need to do anything f about it?

 

Looks like maybe the piston sat in that spot for a while maybe with some fluid in the upper cylinder and it made a mark. the mark looks like the oil control ring. wouldn't worry too much about it nothing you can or should do at this point.
Green scrubber, a couple cans of brake cleaner, and steel wool are your friends here. Be sure to blow out the top of the rings good.
Was rolling my eyes because your focus seems to be on the cleaning and not the assembly as you don't seem to respond to comments such as mine in post #46.

 

Understood. Right now we are focused on cleaning before we put it back together. We’ve been trying to figure out what/how to clean because a lot of the stuff we’ve seen online contradicts other stuff so I figured it’d be best to ask people who actually have this engine and have done the work. I don’t have anyone in my life that I can really ask. I totally appreciate all the advice and input that’s been shared here, but it’s hard for me to focus on the next steps while I’m still on this step if that makes sense.

I’m glad to hear the stain isn’t really a concern at this point. One less thing to obsess over! We have brake and carb cleaner, going out to get a green scrubber - we have steel wool but it sheds a lot more than we expected and my partner’s anxious about the debris.

 

Good. Yes I have done this twice in the last 9 months. If you don't want to do it twice, take my advice above.
Not too sure about the steel wool actually, I think the brake cleaner and green scrubber works best (works better than carb cleaner) and a single edge razor blade were the weapons of choice the first time around. Second time it was relatively clean. Also a 'gasket scraper' for the bigger stuff. Main thing of course is to clean the mating surfaces of the block, this is where novices screw up. Get every millimetre clean or you might not seal right. And Pay Attention to the thickness of the head gasket PLEASE or you'll do this over again. You dont want to soak your IAC or TPS with fluids, keep them dry. Buy some actual CAM LUBE ($4 autozone) and coat the cam and bottom of the lifters, rocker arms where they contact the valves and pushrods, please replace the lifters also you won't get another chance. Dollar store rubber gloves are mandatory also. Lol

 

We have so many gloves lol. We got a Felpro gasket set from Rock Auto. I showed my partner all the **** about the lifters and he isn’t as confused as I am, so that’s good. It’s really his truck so he’s making most of the calls on it (except the new head, he kept waffling about it and I made that call - it was the original 0331). I have all the razors and gasket scrapers we need.

Another silly question: should I be cleaning the rocker arms and pushrods? All are in good shape - no twists or bends or anything. If so, anything special I should take into consideration?

 

Helps to spin the engine over during cleaning also, do this by hand. You should be able to just grab the balancer and turn it with gloves on. If not , loop the serp belt around it and tug.

 

I DO NOT recommend the use of steel wool, Scotch-Brite type pads and other abrasives for this work. They all shed abrasive particles that you do not want to get into oil passages, lifters, between piston to bore clearance, into the oil pump, etc. Preventing foreign object damage is important in this type of work. Steel wool, wire wheels and similar generate bits of steel debris and as they come in contact with air and moisture they form iron oxide, a harder abrasive. Green, red and other color scouring type pads, Roloc discs and related are made with a fiber such as nylon coated with abrasives including aluminum oxide and titanium oxide which are very hard, sharp particles. Getting debris 100% cleaned up from using these is practically impossible. A Google search for something like “use of abrasive pad in engine” will likely identify a number warnings against using such on engine work. A razor blade, clean rags and carb cleaner used carefully is the best solution for this type of work. Don’t risk additional engine issues.

 

You can go on the rockauto site and find the one you bought and they should say. If not, FelPro is very good, just google up "thickness of XXXXXX felpro gasket". You want it to be around the factory .044 or so. Felpro makes the thicker one which you want to avoid, this is where I went wrong first time around. The thicker one had blue sealing material around it. You can use it but you MUST set preload with the rocker shims if you go that route.

Now, ..if you can see through the pushrods, and they aren't visibly worn or damaged, you can just coat them with the cam lube, ...same for the rockers, and pivots. USE the lube! It sticks like glue!! The lobes on the cam and the lifter bottoms are under immense pressure and they are only lubed by splash from the rods so it takes a while to get them oiled. You need the lube.

I did replace all that stuff but you can likely be fine with the old, as long as they aren't worn or damaged. Now would be the time to change them if you are going to and again stay with the oe spec ones. They're of course a little worn justt from the mileage, but they will work fine and the only consideration, again, is how many thousandths they change the preload, but you have a range there of .020 to .060 and normal wear on those components shouldn't throw you out of spec. The head gasket however, will, if you change to a bigger one so I know I sound like a broken record but use the OE thickness on that.

 

Right. Ixnay on the steel wool. The other 90% of my tips are good.

 

So I've been quiet for a bit. I've been sick and we're experiencing a depressive state over here because there is a crack in the wall of cylinder 6.

A moment of silence.

My first teardown. Everything was going well. Or so I thought. We were cleaning the top of the block, vacuuming things out of places they shouldn't be, all the good stuff. And we turned the engine and got 1 and 6 low and everything seemed fine. My partner was doing what we thought would be a final wipe down and clean up of everything - we have pipes and chains and extra hands to lower the head on tonight. As he was wiping down cylinder 6 he caught something and called me and I felt the crack. It's fairly jagged and runs from the piston up almost halfway up the cylinder wall.

So. I'm already into this Jeep for more than I care to admit. To be honest, I really should not have purchased this jeep but we had a NEED for a second car and I know this is supposed to be a 'bulletproof' engine. Ha. When we started this teardown, I told my partner (he's usually the primary driver of the Jeep) that I was in this for the long haul. This Jeep is going to get driven again. The head gasket was most definitely blown so I still feel like the teardown was the right thing to do. I may not have purchased a Clearwater head if I knew there was a crack, but here we are.

My ideas right now are: shop for a new block, look for a junkyard block, pull the block and bring it to a machine shop and see if they can do something about the crack (bore and sleeve it?). I am accepting all suggestions at this point.

 

Ugh! That seems unusual, quite unusual, if it is so. . .. .. .. thinking...Can you post a photo of it? Maybe its a scratch and not a crack? Maybe moving the pistons up and down, some bit of debris got caught in the upper ring?
Also you say the head gasket was bad, can you say where it had failed at?

 

So that crack has a smudge from a finger on it but you can see it. It seems too jagged to be from moving the pistons, and also we didn’t move them too much. Also took all the recommended precautions and did as much as we could to keep things out of the pistons. It doesn’t feel like a scratch - one side of the crack is higher than the other if that makes sense. My partner didn’t want to pull the oil pan to check for any piston skirt debris..... (I have refrained from saying ‘I told you so’ and I deserve an award for that).

At the beginning we did a compression test - cylinders 1 2 4 5 all had around 170/175. 3 was at 85, 6 was at 125. There was a lot of carbon on top of all pistons. Gasket was blown right behind 6.