R34 ticking noise - neo engine

[Danowner]

Ok so I'll attach the video I just took and see what you all think it is. It's started probably about a week ago. My 34 currently has 216,000 km on it, fully stock apart from pod filter and boost controller running 12 psi, and yeah it's just an annoying ticking sound. Not super noticeable when driving unless you really listen for it, but when near something parked up, or next to a car, the noise echoes against it, and it's really blood annoying. In the vid just listen for the constant tick noise that goes up with the RPMs. Just trying to figure out what it is, how to fix it, and if it's urgent. So far with a little bit of research on YouTube trying to match the sound, I've found it could be lifters or timing belt pulley/ idler

 

https://youtu.be/w_6_NSCjT4I

[GTSBoy]

Can't tell if it's mechanical or an exhaust manifold leak from the video.  Use a hose as a stethoscope to listen around the exhaust manifold and turbo gaskets.  If not there, use same hose, or a screwdriver as stethoscope to listen around cam covers, timing cover, etc, to see if you can localise it.  It could be worn tappets causing valve noise, or it could be your VCT solenoid or belt tensioner up the shit, or a number of other random possibilities.

[Danowner]

So just got a screw driver and went on the vct solenoid and all that good stuff, couldn't hear the noise. Went on the right side rocker cover, could hear it, left side slightly but not a lot at all. The closer to the front of the engine I went, the louder it was. The cas was the loudest I could get it. So I'm guessing it's something timing related? Perhaps could be one of the timing pulleys? Not sure if tightening it would do anything though. Another possibility if it's internal, could be oil viscosity maybe? With the KM's its got, I'm running 10W50, did the service last weekend

[GTSBoy]

CAS drive is now your #1 suspect.  Time to take it apart.

[Danowner]

Taking it off, it needs to be back in the exact same location doesn't it? If it's put back slightly different, what would the outcome be? Would the cams just smack against the rocker cover? 

[GTSBoy]

Cams can't smack on the rocker cover.  That's not possible.  They rotate through 360° in there as normal business.  The actual risk of taking the timing arrangement apart and not putting it back together correctly is that you will strike open valves with rising pistons and trash at least part of the motor.  This is not to be contemplated if you do not know how to keep it all together in the right places as you take it apart and put it back together.

I wasn't talking about thoroughly dismantling the timing arrangement though.  Just about pulling the CAS off (and then maybe the upper timing cover too for a better look).  And yes, the CAS needs to go back exactly where it came from, or you need a timing light to be able to reset it.

[Danowner]

I recently took the CAS off, marked my timing cover, got the new one, marked that up (It is a clear one), and put it in. The timing belt looked in pretty good condition, so I decided not to change it. The ticking didn't start anywhere near after doing any of that, so couldn't have been that. If I were to take it off, what would I be looking for?

[GTSBoy]

f**ked bearings, broken keyways, loose came pulley bolts, etc.

[Danowner]

Aiit sick, I'll take it off in a sec and have a look. If there's f**ked bearings, I'm guessing it's common for the bearing to be bulging

[GTSBoy]

Not bulging, no.  We're talking about ball bearings here.  You'd be looking for grindy noises, slop between races, crunchy feel, etc.

[Danowner]

Ok, I took off the CAS. The bearing is making a noise when spinning it. louder than most bearings that I've heard. I took it off, lubricated and cleaned it, and the noise actually stopped for a bit. Then it started up again after about 20 mins of driving. Might try take it off again and properly lubricate it and give it another clean, see if that does anything. Not willing to buy another CAS as they're going for around $800

[GTSBoy]

No.  Bearing is f**ked.  There is no recovery.  Replace bearing if not willing to replace CAS.  Any $800 investment in a CAS would have to trigger a.....well, a change to a cranks trigger - assuming you have an ECU.