I have seen posts about lifter oil starvation, but most seem to involve low (or no) oil pressure. I have not seen a diagnosis for a case where oil pressure is normal. My situation is that I just had a JDM motor installed, and we have oil pressure, but there is an awful knocking/ticking coming from under the passenger-side valve cover. Upon opening the oil fill cap, it's very apparent that no oil is getting up there.

Please see the video here:
http://www.youtube.com/watch?v=GlOhbtm-PPY

Since the pressure seems about right (and noise is only coming from one head), I'd think that most of the lubrication system is good. By referencing the lubrication diagram from the manual, it looks like the oil passes through a check ball and then on to the cylinder head oil gallery.
http://www.300zx-twinturbo.com/cgi-bin/ ... t&total=15
I don't know much about check balls... is it possible that it has stuck closed, not allowing the flow to pass upward?

Any suggestions as to what may be the cause of this and how to resolve it would be greatly appreciated. Thanks!

.: Steve

Hi, I have the exactly same problem rigth now. I removed the heads and spin the crank shaft manually and the second orifice ( with the check valve)in the rigth head is blocked. this hapened after rebuild the cilinder block. now I know what the issue is, but I don't know how to fix it yet.
I already see some engines and no one has the check valve, I am thinking in remove the check valve.....but I not shure yet, until now I'nt see something that could help me.

I am from Mérida Yucatán, México

on mine at idle i get a lifter tick but when im driving it goes away

Has this ever been resolved?? I have the same issue on a vg33

I ended up getting a new engine built by Import Parts Pro and sending the bad one as a core. I wish I had a better suggestion for you on how to unclog it but that's what I did. Good luck!