I do have a free flowing one on front and one at rear has the clicking sound when I shake it, obviously the mechanism inside. It needs to be cleaned, but is still "functioning". It's the one up front that looks like cooked brownies (! perfect !). So, no on the spraying anything in there and using like a bottle brush or something, eh? Ok. I don't know what is meant by tower. But, yes, I do have the turn click kind of CCV 's. Thankfully.
Somebody put in the wrong part for the rear one - it should be a CCV with an orifice. Literally a free flowing elbow but with the orifice it has a tiny hole that lets through a specific amount of air. The 4.0 does not have a PCV valve or PCV system at all.
The one up front is probably all nasty because you have a PCV elbow at the rear that should not be a PCV.
By "towers", I am referring to pieces on the underside of the valve cover directly beneath the elbows holes. They are tubes that reach down close to the surface of the cylinder head so that oil is not flung up from the rockers onto the bottoms of the elbows. I'll post a pic below.
For the record, I don't like the twist lock elbows, I prefer the ones I have as you can find them at pretty much any parts store easily. Sometimes you can find the twist ones but not always.
I think you need to change your rear elbow to the correct CCV with orifice elbow and ditch whatever PCV part is in there.
Here is an example of the valve cover - you can see the two "towers", one by the oil fil cap and one by the rear of the valve cover. turns out they are removable as
@Flyer58 said. I didn't recall mine being that way but like I said it's been a while. Those are what need to be cleaned out most likely, and you need to get the correct elbows installed.
You will still need to remove the valve cover to clean up any of this. If you try to clean from above, you're just going to push the gunk down onto the top of the cylinder head, which could get that stuff into the oil, valve springs, etc which you don't want. I'd just find some time soon and pull the valve cover. I can remove mine in about 30 minutes, so it's not that big of a deal.
It is a 4.0 I realized I had written 4.2 many hours later and was going to change it but this is the first chance I've had to sit and fix my error. I did so much reading yesterday after pulling that CCV off of there, and YouTube videos about it before I inquired but every one of them either takes the cover off, or just cleans the valves. That's why I was wondering if I could spray carburator cleaner in there. Again, thank you for your quick response and willingness to help despite my snafu. I do a lot of work on my Jeep, but I am limited to the lighter stuff due to lack of efficient tools and space/time for big projects.
