Good afternoon. Have a 2001 Montero XLS that was smoking and had lifter noise on start up, 135K miles. Recently went in and changed the valve seals and replaced all lifters (23 were horrible, 1 was marginal). The job went ok and on the first start up everything was fine. Since that first start up it has clattered for about 2-3 seconds when starting after sitting more than a couple of hours. I did a similar job on a 1995 Montero I had at one time and did not have the same problem. Before digging in to deep on this my question is this, are there any inherent oil pump/preasure issues with this engine that need to be addressed any of your are aware of?

Thanks,
I.O.N.