Help me identify this engine sound

[Nux]

This is a '89 3.2:

https://www.youtube.com/edit?o=U&video_id=kboKTcM3KH4

It gets worse when the engine is hot. Disappears over 3000rpm. Sometimes it switches over to a "angry cat rattle" sound (hard to describe). It's quite loud and does not sound good at all!

I first thought it was chain tensioner noise. I have checked both sides and both are good. I can depress the chain a little with my fingers on the right side though. I changed the left side tensioner just because I though the noise came from here - no change. Ramps look good too.

Did the fan belt test, and the sound disappeared.....I thought. Changed bearings and checked the alternator. All is good. Fan does not hit anything. Did get the "angry cat rattle" while the belt was off, so not that.

Pulled all the valve covers. No issues. No broken studs. Rockers and arms are good, and valve springs look ok by the first look (did not test them yet)

I don't think it's an exhaust leak.

I'm beginning to suspect some more serious stuff. Rods etc. What do you think?

['76 911S 3.0]

Your video link is not correct, links to uploaded videos on my own account.

[Trackrash]

These stethoscopes are available at HF for a small investment. Worthwhile to locate a noise.

[Nux]

here's the correct link:

https://youtu.be/kboKTcM3KH4

[Nux]

also: Should I be able to easily depress the cam chain with my fingers (with the tensioner installed)? The tensioner does not buttom out. But maybe it doesn't build oil pressure and thus only uses the built in spring load?

On my other car (a 3.0) both chains were very tight, nothing like this.

[75 911s]

No. The tensioners are very difficult to depress, even using the chain as a leverage or a coin (over the piston while the tensioner is out of the car). You need a vise basically to depress them when they are correct. I recall a thread on priming the carrera style tensioners properly.

I completely disassembled my 3.2 a few months ago. If I remember, the chains were rock solid in there. In my 2.7 there is a tiny bit of slack.

That doesn't sound good at all. You are pointing the camera at the left side in the video, is that where the sound is coming from?

IMHO Clean off all that blue RTV, flatten the covers by sanding them on a glass pane, and use loctite 574 if anything when you put them back together.

[Nux]

well......I'm a little embarrassed:

It turned out to be the fresh air blower!! I was 2 sek away from dropping the engine hahaha

At least I checked that chains, tensioners, valves and springs and cams are all good. And my alternator has new bearings as well. On the road again

[brighton911]

Happy and much cheaper ending. No need to be embarrassed, just about everyone has had such misstep. And it adds to your (and ours) knowledge base.