Click on the video below and you'll hear a loud "Tapping" noise. To me it sounds as something in the valvetrain. Question is what could be making that noise.
I took the oil cap off and made sure oil IS flowing in the heads.

Here are 2 things I'm sure about:

1- It's coming from the passenger side of the engine.
2- It ONLY starts making this noise AFTER it warms up, not the first 5-8 minutes or so.

What do you think this noise is to be sound ONLY after engine warms up?

Any help will be greatly appreciated.

http://www.youtube.com/watch?v=xc9MKxwMPTA

 

Could be a stuck lifter

 

That's a good point and here's why:

I recently replaced the bottom end using a back up short block. I had a HORRIBLE time taking off at least half off the lifters off of the back up block since it didn't run for a long time and I had to use lots and lots of oil to hardly remove them all. So you saying a stuck lifter is a possibility takes me back to what I went through to take the old ones off.
Hmmmm, what's the best way to check if that's what it is? I know it's on the passenger side. Just take the valve covers off and run the engine to see which one is stuck?
Thanks for the comment bro, I appreciate that?

 

Also, why there's no noise UNTIL engine warms up? what's up with that if it's a stuck lifter! shouldn't it make the noise from moment you fire it up?

 

Rule out the accessories first by disconnecting the belt and running the engine. You might also want to invest in a stethoscope to help pinpoint the location.

 

Yeah ^ Stethoscope is a great investment and can really help out. Take valvecover off and check to see if any of the rockers/pushrods are pissing oil out, or if they're not even slightly dribbling. That should help narrow it down (deviant behavior) and the stethoscope will pinpoint it by placing it on each rocker nut (or wherever you think is best) to see which one is louder

 

pc of hose works pretty good as a stethoscope

 

Oldschool tricks ftw..

 

How do you do that? To be quite honest with you guys this is the first time I ever hear the stethoscopes are used to pinpoint problems. Where do you buy them from?
Thanks for everything. I'll take the belt off and see what's gonna happen.

 

Just get a pc of hose a couple feet long, put one end to your ear and use the other end like a stethoscope. It will deaden the other engine sounds and help you pinpoint where the noise is coming from!

 

Damn it I hate this noise

 

Sounds like valve train to me.

 

Just take a long screw driver and use that as a stethoscope, has always worked great for me. I had a similar sound once and it was a couple loose rocker arms. I agree with above, try and rule out the accessories first. Then maybe re-adjust the valves to proper spec and see if the noise continues. If it does then look into the lifters.

 

It really sounds like an exhaust or spark plug leak to me ?

 

 

personally, it sounds a little loud for valvetrain noise to me. especially since it only happens once it warms up, unless the lifter is totally collapsing once hot. U sure the bottom end of the other block was any good? You say it hadnt ran in a long time. The fact that you had a hard time getting the lifters out of the other block should have warned you about using them again. Im assuming they were sludged up, which means you dont change the oil enough. They're likely sludged inside as well, you should have soaked them in some kind of spirits first and cleaned them up b4 re-using. On another note, are you positive its not the bottom end of the block making the noise, like the beginning of a rod knock?

 

Did you pull a valve cover? Did you check to see if you have a loose rocker? If you pull the valve cover and fire it up (Make sure you cover everything for oil splash, a piece of cardboard works well) if you have one that shoots oil out you know it's a dead lifter. To be perfectly honest, it sounds like a valve tick to me, I'd break out the stethoscope and try to pinpoint where it is coming from.

 

hows your oil pressure?

 

to check rockers get an extra valve cover and cut out the middle...

when you replaced the lifters you should have put new in if they were that hard.. geta set of ls7 lifters from the dealership.. like 130 bucks..

 

That sound same problem what i have. Car run great when it was cold, but when warm up, start to make same kind noise. And that noise was really loud. Problem was in one lifter was broke.