S13 SR CAS grinding/squealing? W/video!

[FleetRunner]

I've been working on getting my old s-chassis project out of the back of my shop recently, and I've started running into a really annoying noise out of the front end of the engine. I've been chasing it for a little while now, and have figured out that it is definitely not the power steering pump, and all the other pulleys are nice and tight with no wobble or drag. I keep coming back to the front end of the engine right under the valve cover.

Today I removed the valve cover to look at the top end and make sure my CAS was installed correctly (it was at least a tooth off, but is in right now). There was a bit of polishing at the tip of the CAS shaft where it sits inside the head, so I did my best to clean anything out of there and applied some grease before putting the CAS back in.
What I'm talking about if it's unclear (photo cred FRSport.com)
http://i43.tinypic.com/fkuya0.jpg

After that, the engine ran like a top for a minute, but once it warmed up the noise came back. I can feel vibration through the CAS cap, and when I use a long screwdriver I can hear the noise pretty clearly at the base of the CAS. The noise is RPM-related, for sure. I'm just crossing my fingers it's not the cams, lol.
Video clip of the noise
SR20det CAS noise? - YouTube (http://youtu.be/KYxEM2UQVPg)

Has anyone ever experienced this before? Am I stuck buying a new CAS or is there something else I'm missing?

[fliprayzin240sx]

Did you make sure the cam gear sprockets are properly torqued on?

[FleetRunner]

To be honest, I did not check that while I was in there today other than just grabbing 'em by hand to make sure there wasn't any obvious play. The cams were replaced not many miles ago by a pretty good tech, so that's not a bad place to look.

And this might sound a little strange, but how can one verify that their oil squirters are in fact functioning correctly? There was a good film of oil on the cams and rockers, but I just want to be sure that this noise isn't my cams getting ground down even though it sounds much closer to the front cover.

[fliprayzin240sx]

Pop the valve cover off, disconnect the CAS connection, try to start the car and you should see oil out of the drippers.

[FleetRunner]

Tried swapping in my second CAS today... I didn't have much faith that it'd work due to grittiness of the movement of the sensor on the bench, but I was curious if the noise would change at all, and for the most part it was exactly the same. Silent for about 10 minutes, and then once everything was nice and warmed up it would make noise at about 1000rpm or so. The noise gets louder and quieter while playing with the CAS timing adjustment and I am definitely feeling the vibration through the cap when the noise was happening. Maybe I just have two bum sensors?

These days I've got a bit more time than money, and I had a buddy mention that he can get damn near any bearing you can think of through the machine shop he works at. Has anyone successfully rebuilt a CAS or is it more trouble than its worth? I have seen the RB20 CAS teardown thread, lots of good pics there but he wasn't worried about his bearings...

Anyway, here are a couple more pictures of what I'm looking at. Nothing jumped out at me, but maybe more experienced eyes may see something I'm missing.
Overview under the valve cover
http://i41.tinypic.com/furh2u.jpg

gear mesh seems to be clean without much wear on either side
http://i43.tinypic.com/5v2no.jpg

looking through the CAS mounting hole to where the shaft sits... I initially thought the noise could be coming from here, but there doesn't seem to be enough wear.
http://i44.tinypic.com/1z6rns.jpg

Ideas? What seems to be the best source for a new or remanufactured CAS?

[FleetRunner]

Welp, I attempted to take my spare CAS apart and quickly realized it was more likely I'd destroy it than fix it... so I finally bit the bullet and started looking around for a brand new CAS. CourtesyNissan had the part up for $307, so I emailed them and apparently that was not the "correct" price, that the part was no longer in production, and they'd have to get one from Japan... next month. No thanks...
FRSport apparently had it in stock, though it was stupid expensive... Oh well, at least now I know I should be getting one in 100% new condition and it won't be an issue in the future. But if I install it and that noise is still there, I might be breaking out the blowtorch. LOL...

[Mikester]

It's not your CAS. A bad CAS would never make a sound that horrendous. To me, it sounded like it was coming from under the valve cover for sure, but not necessarily loudest at the CAS. Even if so... no way in hell the CAS could be the culprit.

You really need to remove the cams & inspoect them, the retainers & journals... and make sure the oil squirters are working properly.

[FleetRunner]

Ugh, that's really not what I wanted to hear, but I know you're probably right... I really hope my newish JWT cams aren't f'ed.

[Mikester]

^^Dude... FUCK the cams... I'd be MUCH more worried about the head itself... cams are easily replaced & cheap vs. a cyl head.

[Kingtal0n]

When did the noise start? If it happened after the cam install I would suggest re-installing the OEM camshafts to diagnose and verify it has to do with the cams. Also I would remove the rocker stoppers. go back to basics for diagnosis.

[Mikester]

Given the pure nastiness of that sound, I bet once you get the rocker cover off & cams out, the culprit will be obvious...

[FleetRunner]

I think the cam squrters were clogged... got them all cleaned out and working again, but that noise is still there. Dammit!

The cams actually look okay, they're not the polished pictures of perfection, but the little bit of wear doesn't seem to be that bad. No clear cause of that noise is jumping out at me, and it's making me pull my hair out. I guess the next step is going to be changing back to the factory cams, removing the rocker arm stoppers, finding some factory injectors, and going back to stock. Either that or I'm pulling the whole motorset and going a different direction. It's driving me absolutely insane!

[Sileighty_85]

Almost sounds like a bad power steering pump or one low on fluid

[codyace]

That's your power steering pump making noise. Check fluid level, check to make sure to leaks, and or replace pump.


Edit: Take the belt off and see if sound goes away. If goes away then you know it's pump 100%

[KiLLeR2001]

In the video he posted, the belt for the power steering pump was already disconnected.

[Sileighty_85]

In the video he posted, the belt for the power steering pump was already disconnected.
lol damn thats weird

Maybe Alternator bearings are going out?

[codyace]

In the video he posted, the belt for the power steering pump was already disconnected.

Wow good lookin on that one I didn't even see it!

Man that is odd for sure. Pull alternator belt next to see if it goes away.