Tensioner Pulley Release bolt broken.

You mentioned that 3/4" drive earlier and seemed unsure. A 3/4" ratchet or breaker bar is not commonly in a Craftsman set of tools, even ones with over 400 pieces. Generally, they come with 1/4", 3/8", and 1/2" socket sets. Unless you got a stand alone 3/4" drive set, you probably have a 1/2" drive, which is plenty beefy for any automotive use, I can think of.

I lived on a small island for nine years, and it seemed like all I did was fight rust. I wish you well. Patience and persistence are big helps. Neither is easy outside in the cold.

 

Did you notice in my post #11 above, that I provided a link to a thread that I started a few years ago. Within that thread I posted several photos. Look at the very last photo which shows what the engine looks like with the tensioner pulley, coolant pump and thermostat removed.

Compare that photo to your situation. Can you pull off the pulley now that the nut was removed?

If not, can you drill a hole into the bolt shaft that remained after the top part of it snapped off, and use an easy out to remove the remaining piece of that bolt, without damaging the threads that the bolt screwed into? You may need to use penetrating oil to help get through the rust in the threads.

Thanks also for the photo which shows the snapped bolt was extremely rusty.

 

Tensioner pulley is just stuck to the bolt. Once you get that off rest of tensioner should have enough room to be removed.

Just wedge a screwdriver behind the pulley. If you can get it in far enough you’re pushing from the inner race of bearing and there’s no change of damaging anything.
If you can’t, just force the pulley out. If bearing is damaged just get a new tensioner pulley.

 

Help! I have been googling about my daughter’s Prius noise and I found this chat. I told the mechanic that it’s the water pump and sure enough, the bearing are worn out. Thanks for that. So I bought a new water pump to replace. Now here’s where the living hell has started. The person we bought the car from took it for a time up days before selling it to us. Within days it sounded like a child’s Barbie Jeep whining down the road. Lol. I think here’s why. The bolt that the guy above is talking about is totally missing. But! The belt is still on there and very very tight. I think the guy who did the tune up cut the old belt, and moved the pulley assembly in a position and put a smaller belt on and turned the bolt on the side of the pulley until the belt was super tight. He “jerry rigged” it instead of just getting the missing bolt to do it correctly with correct size belt. And that’s why I think the water pump is screaming and shot. Based off all the chats and google searches. Lol.
So, I need to know if y’all agree and what I should do. Should I just cut the tight belt off and get the correct size belt and get the missing bolt? If so, what in the cornbread hell is the part number for that bolt???? I cannot find it anywhere and the Toyota place is closed for the holiday. I need it today.
Or, do I need to also replace the whole idler assembly, belt and the water pump and coolant?

 

I can’t find a part number for this missing bolt.
Or the right part number for the whole assembly.

 

16630-21020. See my post 11 above which had a link to another thread which explains how to remove the serpentine belt.