Oh my pully
 

I had a coolant leak. Changed the lower radiator hose. Filled her back up and let my friend take the car for christmas. He brought it back and said it overheated or got close and he shut it down and added antifreeze. Ok no problem.
finally got to it today. Turns out the cam pully separated and the grooved portion spun off, didn't damage the belt. The belt slipped back on to the bearing assembly and it chewed up a piece of the fan. There was a bit of a squeal. I thought ok. Coolant leak must be the waterpump.

then in the bottom of my engine bay there was the grooved portion. Oh boy. What do I do now lmao

You sure its a cam pulley not your harmonic balancer/crank pulley at the bottom of the engine? Buy a new harmonic balancer and have somone install it for you and presumably do a timing belt and water pump.

Year and model of you car SC300 or SC400? Sounds like you are talking about a SC300. Sa mentioned about it could be your harmonic balancer separated. If it is a non vvti motor it is non interference so you can replace the harmonic balancer and do a full t- belt, water pump job.

just happened to me monday night. ring is off and car still runs! i have to work. 93 sc300. what do u mean by "do a full t-belt"? i can replace the HB fine but the t-belt? if i just replace the HB, will my timing be off? with non-interference i was thinking i didnt have to mess with lining anything up for timing. tia

timing belt. These cars are all nearly 20 years old or older and doing a timing belt job half of it it getting to the harmonic balancer and taking it off. Then you remove the plastic covers and the timing belt and water pump are right there. Timing belts should be replaced every 10 years or 100,000 miles same goes for the waterpump.

You could just replace the harmonic balancer without having to do the timing belt or water pump were just suggesting if your close do it all. I wouldn't drive your car if you can avoid it as you lost a "balancer" for the engine. I did drive mine from denver to montrose about 5 hours before even realizing what happened i thought i hit a bump and my belt came loose until i was home and could do a real inspection.(my balancer fell off but there was enough left for the belt to ride on)

A new harmonic balance from Lexus is not cheap. I had the same thing happen and ended up throwing a cheap aluminum lightweight replacement on from Driftmotion. Haven't had any issues and saved hundreds.

PS - you can replace the HB/crank pulley without doing the water pump or timing belt. However, if you haven't done the belt and if it's dry/cracked/old it's worth doing at the same time because it's a pain to get the crank pulley off.

If it's a sc300, I have a brand new generic harmonic balancer for sale :)

"I did drive mine from denver to montrose about 5 hours before even realizing what happened"
that is crazy! ive driven mine a total of 60 minutes since mine came off. i wont get the replacement for a few days. thanx for the info.

"if you haven't done the belt and if it's dry/cracked/old it's worth doing at the same time because it's a pain to get the crank pulley off."
that makes sense. i'll be sure to check it out. ty

the belt is still on, just a little loose :P