Valve / Lifter tapping Noise, Rocker Arm, HELP!

[scottpb33]

I have an interesting problem, any help would be much appreciated.

A friend has this 02 Jeep Leberty, he has had since new, and has 87,000 on it. The oil is changed frequently and he has recently had it flushed three times to rid the car of any sludge. The dealer actually suggested this, very strange?

Anyway, the noise sounds like a stuck lifter, valve tap, but goes away mostly when motor is at high idle, but not completely. I took off the valve cover on the passenger side for inspection and started the car up, and did not hear much of anything? I did not notice any sludge buildup, looked clean there, did not noticed anything wrong.

Turned motor over by hand and checked that way also. Chain looked a little loose, but nothing out of ordinary. Car has never been overheated, so I'm assuming the valve seats are ok? From what I have read, there are no lifters or pushrods on the vehicle. I have several posts on here that describe issues with the collars that hold the cam in place, they are missing the 45 degree chamfer. I also saw a few posts about replacement of rocker arms?

The noise sounds as if it is coming from the middle of motor, towards the front passengers side. I did the screw driver method to listen.

I checked one of his plugs, and they are wasted, just about no elctrode left, yet, the dam thing idles perfectly??? The gap I think is suppose to be 42, I measured about 140, how about that!

Has anyone seen or experianced this problem before?

Thanks!

 

[JeepJeepster]

Does it go away after its warmed up? Or does it do it ALL the time? Its normal if it does it when its cold.. Not if it does it ALL the time though.

 

[scottpb33]

It does not go away, it is less noticeable at higher RPM's.

 

[Jeepin Al]

May not be the valve train, I had the same problem and it was loud! It sounded like a burnt valve, or dead lifter. I did evrything short of removing the vavle cover to take a look. The strange thing is that the noise was louder when I took the oil filler cap off, which than led me to believe a pistion slap, or wrist pin problem.

Than I remembered that I cleaned the fuel injectors with Chevon Techtron. And I use mainly Shell gas, with the cleaner in that. Our fuel injectors or plastic. I finally came to the conclusion that it was a injector gone bad. Try this quick fix before doing anything else, buy two bottles of Marvel Mystery Oil, fill up with prem. gas, dump the entire bottle of Marvel Mystery Oil in, next fill up same thing. The tapping should go away, and if it doesn't look at the injectors first, than drive into the valve train.

Al