Engine click or knocking sound on cold start

[deags]

Hi,

I am looking for some help identifying this sound I've recently developed on cold starts. I've had lifter tick before which is much more consistent and 'tingy' - this sounds more like a rattle. Unsure where it's coming from.

Power train is stock standard NA6-
https://drive.google.com/file/d/0B5eiq_ ... tuV3c/view

About 1000km ago 5W-30 was put in it, thinking I need to up the viscosity maybe?

Thanks

[deags]

Fixed link, it didn't survive an edit: https://drive.google.com/file/d/0B5eiq_ ... tuV3c/view

[manga_blue]

I would be starting with all the belts. Obviously first the external ones -alternator/water and PS - checking for crazing, nicks, cracks, etc and then for dents and run-out on the pulleys and wobble/looseness on the harmonic balancer assembly. If that doesn't show anything I'd take the cam cover off and look for damage to the timing belt.

Just in general, when you're looking for noises then a mechanic's stethoscope and a length of plastic tubing are your friends.

[LiteIsRite]

How many K's has it done?

[93_Clubman]

Sounds seems different from one side of motor to the other, so if it persists after checking suggestions above, check for an exhaust leak in the manifold area.

[deags]

Car is at 180.4k km - 5w-30 (Castrol Edge) put in at about 179.3k km if I recall correctly.

All the belts visible from the outside look ok.

It hurts to change the oil after just spending $50 on the Castrol Edge that the wisdom of the internet reccomended, but cheaper than currently that's the easier/cheaper thing to try before I take the cam cover off. When the 5w-30 went in I was warned I should probably be using a higher weight which is why I am dwelling on the oil a bit - but when the engine is turned on the noise goes away after 2-3minutes so I would think using a lower cold viscosity would make it worse not better if when the oil is thinned at higher temperatures there are no noises?

Another concern I have is that if I take the cam cover off and see nothing obvious I'm screwed - I have not had it off before to be able to readily identify what is normal and what isn't...

The noise isn't more distinct on the left or right side - I think it sounds that way because as the camera pans over the left I move it foward and it becomes louder. I think the noise is originating from around the timing belt at the top/front of the engine which is consistent with the change in the volume you hear in the video.

[93_Clubman]

5w-30 (Castrol Edge)
Another concern I have is that if I take the cam cover off and see nothing obvious I'm screwed - I have not had it off before to be able to readily identify what is normal and what isn't...

Here's what the NA6 Owner's Manual recommends for oil:
http://www.five-speed.dk/Download/NAOwnersManual.pdf
And in a very recent ad for an NA6 others mention use of Castrol Edge 5w-30:
viewtopic.php?f=73&t=74986
Re checking timing belt, after removing the cam cover, if nothing obvious regarding condition of belt, ie perishing, splitting, bits missing etc, you'll need to rotate the motor to check the full length of the belt on both sides, so probably easiest to remove spark plugs so no compression or resistance.

[deags]

Thanks everyone for all your input.

I wasn't able to spot any issues and I don't have gaskets to replace if I go taking the cam cover off so I took it to a mechanic for advice. They've heard it before and replaced the AC and alternator belts - I only had this noise a few times and wasn't able to reproduce it but so far I haven't had the noise come back. If it comes back though I'll update the thread.

[93_Clubman]

don't have gaskets to replace if I go taking the cam cover off

Cam cover gasket usually separates from one side easily, therefore leave it attached to the other side, so no need to immediately replace it, but keep an eye out for any oil seepage once you put the cam cover back on, then replace gasket when available/necessary.

[jordan.k]

Mine made this exact noise this morning.

Does sound like it is coming from the valve cover but hard to isolate.

However when i sprayed some wd40 on my alternator belt the noise dissapeared so maybe I'll change that out first.

It went away as soon as i started driving/warmed up

[Ronin]

I guess this is wishful thinking ....

https://youtu.be/1qR_wdHSEZM


Must be a spun bearing right ?

[Okibi]

Sounds almost belt related like a tensioner bouncing back and forth

[93_Clubman]

Sounds deep in the motor at times, but also at times sounds high in the motor.