What's causing my lifters to fail??

I'm starting this question in a new thread as this work has moved past where the old thread started. If you are really bored you can find it here: http://www.aus300zx.com/forum/showthread.php?t=326470.

Snap shot background
Reconditioned engine now done 2500km. Run in on mineral running in oil. Changed oil and filter at 1000km. Then again at 2400km but to synthetic (Royal Purple 10W-40).
Engine developed a clacking noise and I found 3 saggy lifters on the passenger side exhaust valves. Removed, cleaned (they didn't look dirty) and replaced and that seem to fix them.

After reassembly the noise has gone and been replaced with a similar one on the drivers side. Stethoscope tells me it's center of drivers side exhaust valves.

What the hell is going on :bash:[TIS]

One more note. The oil pressure on cold start is 3/4 way up gauge and slowly drops to zero at operating temp at idle. Revving it does bring it up again to just under half. Not sure if this is a problem or could contribute.

http://youtu.be/dsQuX3wDLrc

 

Yep, either you've got a faulty oil pressure gauge, or you have serious oil pressure issues. Maybe oil pump or blocked passages.

 

Could be just hitting lifters randomly. I just had a read of an article in the tech section:

Oh god where do I start now. By the time this car every see the open road I'll be a qualified bl00dy engineer. Time to start working through these I suppose....

Low oil level - no
Improper oil viscosity - shouldn't be for a recondition engine, but might help to increase it
Oil diluted - no
Camshaft, main, or connecting rod bearing worn - not sure
Crankshaft or camshaft journals worn - not sure
Oil pump worn - not sure
Pressure relief valve spring is weak - where is this??
Oil pump intake is clogged - shouldn't be, pressure is good at start up.
Hole in the oil pickup pipe - don't know
Leak in the oil connection line - the what
Oil filter is plugged - no (just replaced)
Low idle speed - no
Oil galleys are clogged - would assume not since problem has shown up in two separate banks on the engine.

So here's another question......is it worth just dumping the current oil and switching to a much higher viscosity oil? What's the down side to this? Any thoughts on if it will help or hinder? If yes then what viscosity?

 

Dump that super duper race car oil and put normal stuff in it. If the problem started when you put the royal purple in, makes sense that you would change that first before pulling your engine into bits. I don't care that some dude on the net is using it and gained all sorts of unicorns. It appears your engine doesn't like it. Go to super cheap and buy a bottle of whatever 15/40 non synthetic is on sale and be happy. They aren't some fancy engine made out of unobtainium that need anything exciting despite what everyone seems to think. And if it actually had low oil pressure, you wouldn't have a couple ticking, it would be rattling its arse off.

 

Thanks TeeJay, might just do that....have nothing to lose. I don't supose these lifters can cure themselves if the oil turn out to be the problem?

 

Just the stock Nissan filter. Oil is Royal Purple 10W-40

 

Thanks Rob, good to hear something positive. It really is much better and the old noise passenger side front has completely gone. So for all intensive purposes it was a fix, just very disappointing that the other side is now noisy.

 

Probably quicker and easier to just replace the oem sender. Gauge seems to be working. I guess I don't really think that this is where the problem lies.

 

My bad, are you going off the factory pressure gauge in the dash. Aren't these next to useless? Get an aftermarket gauge and connect it where the oem sensor is. This will give you a much better idea what's happening with oil pressure. Even a SuperCheap one would be better than the dash gauge.

 

Point taken but I have no room for any more gauges......already have two on the A-pillar and ECUTalk in the dash.

 

I found this diagnostic tool

Shit.. cant believe i have just spent the last 90 minutes searching for engine noises.. ha ha ha.

Anyway, theres one or two there that sound like yours mate.

http://http://www.ratwell.com/mirror/Muir/Muir.html


Cheers

 

LOL...thanks Chris but I know what's causing the noise (it's definitely lifters)....just trying to work out why after fixing 3, I now have new ones making a noise.

 

All good..

All good Marcus... I'm a nut like that.

I went back through this and your other thread and just became interested in seeing if there were any resorces for identifying particular auto / engine noises and there causes. But I must say, I thought it was something heavier than a lifter.

More than anything though, knowing what youve spent in both time and money, and a shitload of inconveniece, I think you will be glad to see this come to an end, and bring your pretty Z on a cruise.

Cheers mate.

 

Simple answer is - Yes.

 

Thanks Chris, ye sit will be nice if I can actually enjoy driving it one day. So many problem considering I started with a new engine...