It's not that bad of a job, it just takes some attention to detail, that's all. A couple of specialized tools that you'll need.... a wrench to hold the cams while you break the bolts loose, and a long harmonic balancer puller to get it off / back on. The puller you can rent at most parts stores, but the wrench you'll either need to buy / make. In a pinch you can use vicegrips, but it's not really recommended. Take a million digital pictures and mark / bag all the bolts. If you can't get the exhaust manifold bolts out consider loosening / cutting the manifold to Y pipe bolts instead and removing the heads with the manifolds. This way you have some more room to get the bolts out later. Putting the heads back on is easy, except the drivers side one is a bi*tch to get back in place because it hits the brake booster. Having a spare set of hands helps.

Consider removing the radiator / support to give yourself more room. It'll make it easier to get to the timing chains for alignment. Be careful when removing bolts from the front end, the top of the oil pan is open and it's easy to drop small parts into it. Stuff a rag into it AS SOON AS you get the timing cover off.

Take your time, examine all the parts as you remove them, & replace / rebuild as needed. Ask questions here, theres a ton of experienced people available for help!

Bob

 

well, so far so good. tore it down today and made some pretty weird discoveries. one rocker arm on #2 cylinder somehow came off and was just laying in the cavity. noticed some gouges on the lobe for #2 and a gouge in the head (both minor). weak valve spring? Can i simply replace the rocker arm and pray? Still dont why there was low compression in #3. all looks good on the surface. will do more digging tomorrow. p.s. any one know of a place that rents the valve spring depresser tool (ratchet type) that hooks under the camshaft. Cant seem to locate one here, only the screw down type, and I dont know if that will work...
THANK YOU ALL FOR YOUR HELP!!!!!!

 

PSS The timing chain DID NOT skip. it is turning right on time!

 

A bad lash adjuster can cause the rocker arm to come off, but I don't get how this will cause NO compression on this cylinder? Without a rocker arm in place the valve should remain closed on either the intake or exhaust stroke (depending on which valve it was) but it should still indicate SOME compression while turning over.

I believe the correct way to replace the rocker is to remove the camshaft first, which also means pulling the timing chain(s). No need to compress the valve spring unless you're pulling a valve. I've only used the "C" clamp style spring compressor with the head off the block, but I'd imagine that screw down one would work provided you have enough room to hook the fingers under the spring.

Have you taken the head off the engine yet or did you just lift the valve covers? You may find that the valve in question "floated" and the seat is gone. This would explain the no compression as well as the dropped rocker arm.

FWIW, any marks on a cam lobe are going to cause a problem pretty quickly. You may be better off looking for a cam to replace it with. (boneyard item).

Bob

 

This happens on the 4.7L sometimes. I would replace the entire cam and bad rocker from a donner at a junk yard or new.

I'm still with Bob, it is hard to say there isn't a internal issue because of no compression, however if the rocker fling'ed off and landed between the valve and valve cover holding it slightly open then I could see it.

Sense you are down there anyway I would pull the heads and have them checked and cleaned and install some good head gaskets like Mopar Performance or Fel-Pro PermaTorque.

 

Will hopefully get the heads off tomorrow. As suggested by many sources, I am taking my time and labeling everything. Got the intake manifold off today. Gotta hit the parts store for some tools! Thanks again for "holding my hand"!!! Will check in again tomorrow.

 

"we did have overheating problems with this vehicle and this may have contributed to the problem."

Sorry, I missed this earlier in the thread. If you overheat a 4.7 more than a couple of times it's pretty much a sure bet that you're going to take out a head gasket along the way, or possibly crack a head. Examine the gaskets before you peel them away from the block or head (whichever one they decide to stick to on removal) and look for telltale water leakage signs. Then check over the head in the same area to look for cracks. Make sure to check the heads for warpage with a straightedge & feeler gauges as well. If you find a flaw check into rebuilt heads vs. machine shop labor on repairing yours, it may be cheaper and quicker to replace them.

Good luck!

Bob

 

That's one magic loogie!!! (Seinfeld reference in case you don't get it)
Sorry, I couldn't resist!



www.youtube.com/watch?v=WEzBeP6pRoY

 

That was a good one.......


Yep! Head gasket.

 

Well, could be a problem. Taking head off pass side and discovered one valve (#2) is lodged sideways in the cavity preventing me from lifting the head. I don't have the spring compressor and noone round here in bfe seems to to know how to get one. I am assuming if I remove the spring and keepers the valve stem should slide out? Gonna work on the other side and wait to hear from yall.