HALP me identify mystery engine noise.

So this is my boy's 92 L03 with about 150K on it. It's been leaking a bit of oil (not horrible amounts, but a quart every few weeks I guess). The last documented change was 9K ago when he got the car. We both think it's been done in the interim but no one wrote it down. Oil smells fine, changed it tonight, nothing unusual, just the standard couple of metal flecks in it

Anyway when he pulled into the driveway last night I heard this noise. I don't like it. It seems to be centered in the middle of the motor (not on either bank). Please excuse the crappy cell phone video and darkness but it's primarily an audio recording.

I would like to hear your opinions please. I have one but I don't want to prejudice anyone with an idea.

thanks.

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Engine at idle. Wind noise from the fan. the red thing at the end is the water pump (put the phone down over it by front of block).

I'm thinking it's the fan hitting the shrowd or make the flexplate hitting the inspection cover. It's too fast and "ticky" to be bottom end.

The only bottom end issue I ever had was I broke the crank in two. There weren't noises other than a really loud BANG at 4000 RPM as I shifted and the rear wheels locking up when I let the clutch out....

doubt it's the inspection cover, as when we put the vette starter in one bolt was hitting it, so we shimmed it with washers and such. And the cover is plastic, this is metallic.

I'm thinking water pump bearing maybe?

X2 on the fan,.

pull the belt ,. see if it,s still noisy,.

Nick

belt pulled, noise stopped. Found the pulley on the spring to be wobbly and loose
although it still made that noise afterward. Stood on the drivers side and goosed the throttle and got hit in the head with little chunks of most likely fan shroud and the noise stopped


Yaaay.

What do I win?

Cerveza fria en la playa! Just come on down.

Crovo, Translated that means you won  "little chunks of most likely fan shroud"

A noise like that, albeit at a higher frequency, could also be a failed ignition coil ticking as it arcs internally with every firing. I had that happen to me on my '94 RMW - sounded like the AIR pump until I unplugged the airpump and still heard it, very rpm dependent too.

Sprocket wrote:

Cerveza fria en la playa!    Just come on down.

Woot! See ya Saturday morning!

lakeffect wrote:

Crovo, Translated that means you won  "little chunks of most likely fan shroud"

Not gonna lie. I lol'd.