Clutch Throwout Bearing Noise?

[RDKeysor]

Have just surveyed the extraordinary number of posts under the forum's throwout bearing topic without learning anything about my (latest) Healey noise. This is a '60 BN7 with a Toyota 5-speed installed by a previous owner. The clutch pedal effort on this car is very light, and I have experienced no issues with it. Now I have a whirring noise that follows depression of the clutch when shifting from first to second and from second to third gears. It just starts and then vanishes when the pedal is released. Not really noticeable upshifting for fourth or fifth, nor when underway. A friend who probably knows less than I do offered a suggested problem, the throwout bearing. I plan to continue driving the car until the noise goes away or the noise reveals itself by a part failure. I assume I can pull the transmission out through the cockpit if I need to expose the clutch. Since we should always look at what work preceded the latest possible problem, I will say that I recently installed and reinstalled a Chinese-made aluminum radiator. Can't figure any connection between the sound and the radiator work. I will eventually post my experience with this radiator, but first need a period of really hot weather here in North Florida before authoring one of my typically windy posts. This radiator replaces the stock version which I had rebuilt shortly after purchasing the car five years ago and supposedly upgraded without noticeable improvement in running temperatures. Doesn't that sound familiar?

 

[Bob_Spidell]

Does sound like a throwout bearing. You'll know for sure when it grenades and strands you on the side of the road. For better or worse, the OEM release bearing--really, a graphite disk in a metal shell with no moving parts--shouldn't make any noise until it's worn completely down to the metal shell; which, unless you really ride your clutch or live in San Francisco should last as long as your clutch.

 

[steveg]

Toyota uses a ball bearing TO bearing. That could account for the whirring. Smitty setup also uses the Toyota ball pilot bearing fit into an aluminum ring in the Healey flywheel.
...FWIW