Have a 92 rs with 3.1v6 and regular hydraulic lifters. After it gets good and hot it has some really bad lifter tap. Opened her up and despite it's age and high milage, (205000), the inside is actually pretty clean, hardly any sludge at all. Thought I had a bad lifter but they look surprisingly really good.

I did have a few that seem to be clogged, sprayed parts cleaner through them, a couple let it barely seep through and a couple I got nothing, so I figured that would explain my tapping. All push rods good, no blockages there.

I know it's not standard procedure to put new lifters on an old cam, so would it be better to try to get my old ones flowing or is it safe to get some new ones?

 

I wouldn't put new lifters on the used cam. Are the lifters on the V6 adjustable at the rocker arms? Sometimes you can loosen and run them down a couple times, then adjust to spec, and stop the rattle. Oil pressure good when hot?

 

I second oil pressure reading. My 6.2 had lifter tick at startup from a spun rod bearing until the pump built enough pressure to compensate.

Adjust the valves and see if that helps/eliminates the tick.

I've had decent luck with BG oil treatment. Add to a cold engine, let idle for about 20 minutes, shut down and immediately drain. Even with fresh oil it's amazing how black the oil is that comes out, and the smell is horrid.

I would think if it's still ticking/sticking after that and adjusting the valves, you most definitely have a lifter going bad.

 

I'm gonna clean them out and put them back in see how it goes. A few were a little loose, I mean you could rattle them with your fingers but just a little. If it still does it after I'll check oil pressure manually, should have done that already but slipped my mind.
Like I said it doesn't start until motor is good and hot, have to let it run for twenty minutes or more before it starts, and I already tried some higher viscosity oil, and run atf for a little while and change the oil for a clean out, but no real change.

If the oil pressure is low only on the hot engine, would that be the oil pump itself or a worse issue?

Even for the high milage the old thing doesn't smoke, runs great until the tapping starts, it will rough idle and stumble a bit. I can go a month without even cranking it and it fires right up like nothing, so would really like to get this tapping solved