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Long story short, my coolant system ruptured which has led to at the very least a blown head gasket. I have decided to replace the entire system and convert from a closed system to an open one.
Now as for the Head gasket. I've already ordered a lot of gaskets that will need to be replaced. And while I'm that far into it in going to go ahead and install a new water pump. Now assuming the Head is ok should I go ahead and replace the pushrods and rocker arms? I will not be messing with the cam. What about the lifters? Where does the wearing of pairs end? I've seen some say just do the lifters and some say it has to be done with the cam.
Also, I'll be into the engine pretty deep without removing it from the truck. Are there any other preventative items I may as well change out since I got it apart. Don't really want to do valves but would I be money ahead to replace them? All assuming the Head is good. It's all original with 111 thousand miles on it. Renix Inline 6.
If the Head is cracked I'm actually entertaining putting in a new engine. Maybe even if it just needs to be machined. Dollars add up quick and the cost of new one isn't that much more....no headaches afterwards. I can easily see this costing a thousand bucks. A new crate engine can be gotten for 1400....a stroker kit with block for 1700.
 
89 Comanche
Eliminator
2wd
4.0L
5 speed PukeGoat
Factory Original
 
 
 

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That is a really hard question... You really have to open it up to know. Pull the head and have it checked for flatness and then check your rockers and such and compare to FSM specs is your best bet. If they arent out of spec or nearing out of spec why replace them? Now you can go with roller rockers which MIGHT free up a small amount of HP (don't count on it without cam and supporting mods), but other than that? 

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My .02c, I would just put a new head gasket and water pump on it and call it good (assuming the head is not cracked).  111K is nothing, and if your valvetrain wasn't having issues beforehand there's no sense in replacing them just because.  You can install new rockers and pushrods with the head installed if they start to cause any issues in the future (doubtful, though).  Lifters/cam are another story though.  You have to pull the head on a 4.0 to pull the lifters (2.5's can be pulled up through the head).  New lifters on an old cam are "ok", but a new cam on old lifters is bad juju.  It's better to just replace them all as a set, and if you're replacing the cam, it's a good idea to replace the cam bearing in the back of the block, which is a whole other can of worms best left alone if no problem exists.

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My .02c, I would just put a new head gasket and water pump on it and call it good (assuming the head is not cracked).  111K is nothing, and if your valvetrain wasn't having issues beforehand there's no sense in replacing them just because.  You can install new rockers and pushrods with the head installed if they start to cause any issues in the future (doubtful, though).  Lifters/cam are another story though.  You have to pull the head on a 4.0 to pull the lifters (2.5's can be pulled up through the head).  New lifters on an old cam are "ok", but a new cam on old lifters is bad juju.  It's better to just replace them all as a set, and if you're replacing the cam, it's a good idea to replace the cam bearing in the back of the block, which is a whole other can of worms best left alone if no problem exists.
Yep...I see a big can worms just waiting to jump out. I can afford to piecemeal or get a new engine...but not both. Piecemealing it adds up quick. And I've always been of the opinion if I have to pull the engine (camshaft) I'm putting a new one back in. Pull and rebuild isn't much cheaper than a new install.

89 Comanche
Eliminator
2wd
4.0L
5 speed PukeGoat
Factory Original


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