Hi I went and started my car today. Its a 91' accord 5 speed with 170,000 miles. When I let it idle in neutral I hear a whining type noise, but when I depress the clutch pedal the sound goes away. Is this normal or not? It sounds like release bearing but not quite sure.

 

I had this same issue after I did my swap when my engine was down for a while and I think that rust occurred on the ball of the slave cylinder and as the car was moving it was shaking back and forth.

Spray some silicone grease where the ball of the slave cylinder engages the piece next to it.

 

Most likely release bearing.

 

Could be, but not always.

3 dollar fix vs tranny removal is a no brainer