justforfun

sound like it is the oil pump or oil pump drive gear in the back of the motor, but it only makes noise for a minute or two when it is cold outside. Has anyone had this happen?

both parts only have about 1000miles b/c i chewed up the driven gear and had the pickup disk break off the pump.

any ideas?

Josh Z95

On start-up I do have some loud kinda whin noise, but only when cold and only lasts for a minute of so.....

DDZ/28

Lately I've been getting the same thing. The colder it is the longer it lasts...no more that a couple of minutes though. I tried finding out where it was coming from and could swear it's the alternator.
Makes me nervous everytime I hear it

Hyperspeed97z28

I get the cold WHINE for a min or two been below zero in the am here though..

Josh Z95

Does anyone know what is creating this sound, how to fix it, or if it is a bad thing. Doesn't really sound like a good thing though....

justforfun

i am in SC so when i say cold i mean below 45F or so. I thought it was the alt for a sec but i am positive mine is in the back of the motor. It is loud enough where i could detect it even witht the exhaust noise while i was inside the house.

Just brainstorming, could it be the cam walking to far back?
When i get a chance i will look for metal on my magnetic oil drain plug.

DDZ/28, if you think yours is the alt take off the belt and see if it goes away.

Seta

Totally 100% normal. My Z has been through 8 winters and on cold days that happens everytime. The key is also harder to insert on a cold day. Just the way it is, no harm no foul.

red

You may be hearing piston slap. It's very common on the LS1's and some LT1's will have it also. When it is very cold the piston will shrink more than the block and will make noise untill it warms up and expands back to tolerance. That is why you hear it only for a min or two. It is also very hard to tell where the sound is comming from since it is basically comming from all eight cylinders. If you are familiar with the sound you will hear it right away.

CODY BEHNKE

Same here, After having a LT1 for two winters you get to know the noises they make when it's -20 outside.