valvetrain rebuild

Found milky oil in my 2002 4.0, TJ, I know this is the XJ forum...same engine, more knowledgeable forum. I replaced the head on my 2000 XJ a few years back, runs great. Now for the TJ, the head casting is 0331, has TUPY (updated version...?) stamped between 3,4 cylinders. I pulled the valve cover, could not find any signs of the hairline crack that was present in the old XJ head. I suspect it's a bad head gasket, but i'm ordering a new head anyway. I had ticking for the last year on startup, suspected stuck lifter. Ran tranny fluid through it, seemed to stop, sometimes ticks on start, usually lasts for about a few seconds. Since I'm tearing the old head off, I plan to install new lifters, new pushrods, new rockers, new pivots, new bridges. As long as I buy exact stock replacements, is it as simple as dropping them right in?

Thanks

On a stock engine, it is usually as simple as dropping them in. I would inspect the rockers and push rods for wear. If they are good reuse them. They are easy to get to any how to replace once the head is back on. If you have time you can always take your original lifters apart and clean them. If you do clean your original lifters, keep in the same order they cam out so they go back on the same lobe. If you do use new lifters you must do a cam break in procedure. You can google that, but it typically means coating the lobes and lifter foot with a cam break in lube (not engine lube), then running the engine around 2000 RPM for 20 minutes.

Also, the tick could be a lifter bleeding down when sitting or an exhaust leak. Personally if its just a few seconds I wouldn't worry about it.

Thanks for the reply!!

TJ has 138K on the clock, I'm surprised, I'm having issues, then again, I bought it off this chick, and I'm pretty sure she beat on it....totally unrelated...I eventually took her clothes off at one point.

When I replaced the 0331 on my 2000 XJ @ 170K, I pulled the lifters to have a look, and just put them right back in, they didn't show any obvious signs of wear, I also never had any weird noises.

I wasn't aware the lifters could be taken apart. I figure, if it's ticking, it'll need replacement, hence the need to replace everything above it (rods, rockers, pivots, bridge caps). And since I'm digging fairly deep into this, I don't know what I'm going to find once it's open. I had an exhaust leak after I installed the new head on the XJ, I'm familiar with that sound, don't believe it's that. Would a sticky lifter, or lifter bleed down be indicative of a faulty lifter?

Could be faulty, could be a piece of dirt lodged in it. Stock spring pressures really shouldn't make a lifter bleed down to the extent that there is lash.

I guess I am missing the point of replacing the head.

You have the improved TUPY casting, so just have the head pressure tested at a machine shop.

I'm getting the cooling system pressure tested this weekend. Coolant is going somewhere at a fairly rapid rate, and I haven't been able to find any source of leakage externally. If it is a head gasket, I'd rather have everything I need in case there's issues with the head. Then the issue of this occasional nasty ticking, I don't know what I'm going to find.

GreenXJ2K said:

I'm getting the cooling system pressure tested this weekend. Coolant is going somewhere at a fairly rapid rate, and I haven't been able to find any source of leakage externally. If it is a head gasket, I'd rather have everything I need in case there's issues with the head. Then the issue of this occasional nasty ticking, I don't know what I'm going to find.

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I understand, just hard for me to justify replacing a head without testing first it first. atriot:

x2 on the head. If you take it off I would have the guides checked, valve sealing checked and flatness checked. If you are concerned about cracks you can have it magnafluxed. You can also pull the plugs and check for wetness on them as well as shinning a light down the plug hole to see the top of the piston. If a cylinder has been getting coolant in it the piston will be a lot cleaner than the rest.

Also, if your oil is milky stop driving it or fix it ASAP. Coolant in the oil will eat up bearings pretty quick.