Liquid_Cure

This is my first time posting, but first I would like to say thanks to all the helpful people that respond to everyones questions, I've found a lot of good information for my 97 Cherokee 4.0L

Here it goes, I'll try to be brief, but it detail explain how I got here so other people can get advice from this as well.

I've owned my cherokee for about 6 months I bought it from a friend who bought it from the original owner, He said that when he bought it the water pump and radiator were bad, and needed to be replaced when he sold it to me he said that its took a little too much water when he brought it over cause he was not driving it at the time.

Anyways... It was running fine, until it started running rough when cold, but once it warmed up it was fine, It was also showing a check engine light now, Misfire cylinder 3 and 4. I changed the plugs and wire. They looked like they have never been changed even at 120k. Then the roughness progressively got worse, until one day I went out, started it with the hood open and noticed that the manifold was blowing smoke right at the weld like I have read so many times before. (steam actually) and sure enough 10 minutes later, white smoke from the back. So I blew my head gasket, And Im at the point now where, the head is removed, its at the machine shop, for re-surfacing and a valve job ($159). However I removed the head with the rockers still attached, and the rods stayed in the block, barely. So Now when I get my head back, Im not sure what to do. Do I place the lifters back in the block and very carefully place it down, or Do I RE-Remove the lifters and then put the rods back. The only thing i'm unsure of is how tight to make them, I read something until they barely touch the spring, but also to torque them to 20lbs, What kind of problems am I going to have doing this, I have never messed with lifters or rocker arms before?

Also I plan on buying a new head bolt set, because it was recommended, but do you think its also as important to buy a new intake exhaust bolts, they say the threads get stretched because of heat. FYI My gasket blew a hole in it in one of the covered holds dead center of the two middle pistons.

Thank in advance.

5-90

You should not need to remove the lifters proper - in fact, don't unless you're replacing them! If you get them mixed up, you'll wreck your cam...

(NB: "Lifters" are the metal slugs that ride directly on the camshaft, and are under your pushrods.)

When you put the head back on, simply pull the pushrods out and set them aside. Put the head in place, torque it down per FSM, and the remove the rockers and set them aside (in order would be preferred.) Drop the pushrods down their holes, make sure they're setting on the plungers in the lifters, and then put the rockers/pivots/bridges back on. Finger-tighten the screws, then get out your large ratchet with a 3/4" socket to turn the crank. On each cylinder in turn (with both valves closed,) torque the screws to 19-21 pound-feet. Done.

When installing the valve cover, coat both sides of the gasket (if cork) with an even layer of RTV Black. Set in place (I usually stick it on the bottom of the valve cover, then set the cover in place) and finger-tighten the valve cover scews. Break for a sammich and a soda - come back in a half-hour.

Torque the valve cover screws to 7-9 pound-feet (or just use your fingertips on the head of the ratchet - do not use the handle! Too much torque will crush the gasket, and it will leak and require replacement!) If you need replacements, valve cover screws should be 1/4"-20x1"

For the manifold screws, I prefer to use silicon bronze when possible, or SAE Grade 5 screws when not. It's not so much that the threads stretch (they're low-torque screws,) but that the heating and gradual cooling causes steel to soften (it's called "annealing,") and steel exhaust screws should be replaced every time they're removed. SAE5 screws lose strength more slowly than SAE8 - SAE8 is more sensitive to annealing (verified experimentally.) I also find that a thin, even layer of RTV Copper on both sides of the exhaust gasket rarely goes amiss. Manifold screws should be 3/8"-16x1-1/4". You can get them at a well-stocked hardware store. Cut new end studs out of brass threaded rod - I usually cut them to be about 2" long. Studs should be at least in the two extreme end holes - they allow you to "hang" the exhaust in place while you wrestle the intake down and start some screws. Be sure to reuse the funky bowl-shaped washers under the original screws - they're actually there for a reason!

Just to clarify...

This link will take you to a picture of a valve lifter - Lifter/Tappet Pic

And this one will take you to a pic of a set of stamped rocker arms (should be similar to yours) - Rocker Arm Pic

MS Fowler

If I understand your question...
The lifters ride directly on the cam. Make sure they are installed BEFORE you set the head and gasket on top. It may sound silly, but make sure that the lifters are right side up. I mention this because you made a note that they BARELY stayed in the block. It might be poosible that one came out and flipped over before it dropped back down. Just check to be sure.
Install and torque the head following the proper pattern. Then install the pushrods in their bores. Then bolt the rockers on top. Make sure the push rods are clean.

Liquid_Cure

Sorry, Your correct, when I said lifter, I meant pushrod. OOPS. This may seem like a stupid question, but you did a great job explaining it, but I'm not sure, how I would know if the valves are both closed since they are now sitting on the block and I cant see them anymore, Can I tell by looking at the rockers, will they be down, or up? I'm assuming Up, And Do I do this After the head is torqued down? or before. Also, I have a rubber gasket on my valve cover? How town should this be, also its pretty thick, and has metal in the inside

Also I am curious about this RTV Copper on the intake exhaust gasket, I have a gasket that came with my new manifold, and the one that came in the fel-pro kit, neither of them look like they make a REAL good seal without some serious pressure. Tell me more about this if you can.

Also thank you for the very detailed information, Im gonna head out tommorow morning(noonish) and pick up those bolts.

Liquid_Cure

OH ALSO! I did a great job, of marking which bolts go wear, and what direction and what place by sticking them through a peice of cardboard. However I did the same thing with the PUSHRODS, but I don't know which side is up or down? I honestly didn't know they were different, this makes me nervous. I even know which lifter they go on, but not the direction

MS Fowler

Nice write up from 5-90.
The only nit I would pic is where he recommends coating BOTH sides of a gasket w/ RTV. That essentially glues the cover to the head, making the next removal all that more difficult. I was taught to RTV the gasket to the cover, and then install the cover to the head or block as applicable. After all, the purpose of the gasket is to make the seal and prevent oil leaks. The RTV is used to keep the gasket aligned until the cover is installed and the bolts are in place.
If you were using the RTV in place of a gasket, I would suggest laying on a thick bead on the cover, and then taking your sammich break, allowing the RTV to begin to cure. Then bolting the cover to the head.

Liquid_Cure

Ms fowler, are you refering to the head gasket the exhaust gasket, I think 5-90 was saying only RTV the exhaust gasket.

MS Fowler

I thought he was referring to the rocker cover, but my advice applies to all steel covers on the block or head, i.e. oil pan, lifter cover ( if used).

I would NEVER RTV a head gasket., nor anything on the exhaust system. RTV is not made for those temperatures.

5-90

Never ever, not ever, apply any sort of sealer to a modern cylinder head gasket! Earlier gaskets used spray copper to seal, more modern gaskets are composition with a printed sealer in spots with additional sealing is required!

The cork valve/rocker cover gasket usually wants a little help. The overmoulded rubber gasket (which you seem to have) theoretically doesn't require sealant, but I've not worked with one. Torque values will be roughly the same, and for similar reason.

RTV Copper works neatly on exhaust gaskets - it's high-temp stuff, and the inline sixes could use the help (especially with the side-draught heads we all have. The RTV helps to make up for the differential expansion of aluminum vice iron/steel, and will help keep the gasket from burning out until you get to it. I still check torque annually - and I invariably find a couple of screws loose when I do.

(If you want to use threadlocker compound, you may use LocTite #272 - or equivalent - or don't bother. Nothing else will stand up to the heat.)

As far as RTV-ing the rocker cover down - I've not had any trouble removing it afterwards. Grab my 7/16" socket wrench and my 2# rubber mallet. Remove the screws, fetch one good swat on the pax side middle of the rocker cover, and it breaks loose without any trouble at all. I said "even" - but you don't need to get silly with the stuff... You probably don't need as much with the stamped steel covers, but all of the covers I've dealt with are cast aluminum (I mainly work on RENIX for people...)

Pushrods may be reversed or mixed without incident. Rockers should go back where they were removed. Lifters must go back in the very same hole they were removed from, unless they're being replaced anyhow.

Moncheche

Fantastic write-ups! I'm in the middle of this project and this type of advice keeps me from slamming my head on the concrete.

Thanks again!