2004 Charokee 4.7 with constant valvetrain chatter after head gasket replacement

[mswogger]

Hello. I've been searching for likely next steps on fixing a 2004 Grand Cherokee 4.7, but have run out of known options. I'm hoping someone has experienced this issue before and has some advice on where to look next. Here's the back story and what I've done:

The engine overheated due to a popped radiator hose, and subsequently lost a head gasket. The engine was running perfectly fine, but had coolant steam in the exhaust
- I replaced the head gaskets and had the heads surfaced
- Upon running the engine, there was noticeable valvetrain clatter on the passenger side. It sounded like sticky lifters
- I replaced the lash adjusters (overhead cam equivalent of lifters), and the noise was gone for two 5+ minute test runs
- The third time the engine was run, the noise was back
-> I ran the engine for about 15 minutes to thoroughly circulate oil and warm it up
-> I took the vehicle for a test drive
-> The noise only got worse
- I performed an engine flush in case there were blocked oil passages, but the oil came out perfectly clean and the noise was no different
- I also added Hyperlube after the engine flush (also no difference)


After all that, I pulled the passenger side valve cover off again and removed the new lash adjusters. I found that I can completely collapse half of them by finger pressure, and the other half of them I can mostly compress but not quite bottom-out. I figured there would be enough oil in them that I would feel a lot of resistance, but that isn't the case.
I soaked the lash adjusters in oil for 24 hours, and three times during this period I operated the adjusters by hand in the oil. This didn't make much difference to their "feel", and no difference to the valvetrain clatter once reinstalled.


This is exasperating. All of the threads I've seen on these engines pertaining to valvetrain noise are either due to a rocker arm falling off, or the noise only lasts for about a minute after startup (not always present), thus, not relevant to my issues.


Any help....?


Thanks

 

[drewbuddy]

Some say to prime lash adjusters, but when running should fill with oil. I didn't and had a terrible clacking until they filled and it eased off. But you said they were new, so unless they are defective or if the bleed is stuck open(if there is one) You could try bleeding and prime them, if you can, may or may not help. Just idea for you to check because something similar with a friends vehicle, I would check the timing chains for slack or if they stretched because it can slap against cover or whatever its hitting and give that noise. Was kind of mind boggleing till it was found. Also verify condition of your tensioners, again because the loose chain can slap and give that illusive noise

 

[mswogger]

Thanks for the reply.

Since I posted, I actually pulled-out the lifters from the passenger side, soaked them in fresh oil for 24 hours, and pumped them by hand in the oil three times across that timespan. I was surprised that after all that I could still bottom-out half of the adjusters in the oil with my fingers, and the other half would compress nearly all the way, since I'm used-to small-block Chevy motors where a pumped-up lifter is firm. After re-installing, the noise was no different.

I've he about the chain noise, but the noise I hear is distinctly from the side of the motor rather than toward the front, and there was zero noise before the head gasket replacement, the noise went away for a bit after replacing the lifters, and the chain doesn't "seem loose" after I reset the cam timing.
Buuuut, worst-case, if I don't find a solution, I may end-up replacing the timing chain and adjusters just to make sure >=(

 

[mswogger]

When I bought the lash adjusters, it was economical to buy an entire set instead of just for the side making noise. But I only installed new ones on the side with the issue. Thus, I still have 8 new adjusters, and decided I'll try soaking those in oil and installing them. I was surprised to discover that the new ones out of the bag ARE as firm as can be, and I can't compress them at all by hand (I can't remember attempting this with the other 8 before installing them the first time). My fingers are crossed that this time the noise will go away again, and STAY gone. But, I also devised a little test to perform during the procedure: I'm going to remove all of the adjusters from the passenger side, re-torque the cam into place, disable the engine (pull the ASD relay), and crank the motor to see if oil pours out of the lash adjuster holes. I figure this will tell me if there is an issue with oil getting to the passenger-side head. If I don't see oil, I can try to figure that out (and that would be hell). If I see oil, I'll proceed with the other new adjusters and hope for the best.

I'll report my findings either way.

 

[mswogger]

I finally got it sorted out! I verified it wasn't getting oil to the passenger side head. After blowing compressed air into all the lash adjuster holes and not fixing it, I decided I needed to pull the passenger side head again and verify the oil passeges that way, possibly blow air through the head and block, and inspect the gasket.

The hole in the head gasket for the oil passege was missing

Take a look at the photos comparing another new gasket to the one I had installed. The gasket I installed was defective as it is missing the hole to let oil into the head.