1990 celica Thermostat nut stuck- does soemthing else have to come off?

[Knix]

We got the top bolt off no problem, but the bottom nut is stuck, we let it sit overnight with penetrating oil on it and its still stuck. There is either the power steering pump or some other needed equipment blocking us from getting a socket on the stuck nut. (we have the 5sfe engine)

Now it looks as if we have stripped the nut, and my DH things that the only solution is a very small vise grips needle nose to lock onto it to turn it. My question is:

1. do we need to remove the silver round mechanical thing in front of the thermostat to be able to access the nut with a socket?

2. will the tiny needle nose locking pliers be able to turn the nut when an open end wrench and the round end of a wrench 10mm has failed?

Any other suggestions. and yes we are having an overheat problem. cronic and sporatic water loss (coolent o/f bottle seems to have a hole in it about 1/3 of the way up)

[alltracman78]

The AC compressor is underneath the therm housing, but I don't remember it being in the way. It may be though.
To get at it with vise grips you'll have to remove the AC compressor. Don't forget the lines have freon in them, so be careful with them.
I'm not sure what the silver round mechanical thing is, but if it's in the way, you probably need to move it.....

I would start with a 10MM deep socket. Slide it on and make SURE it's on the flats of the nut, then whack the end of the socket with a hammer to seat it on the socket.
Then, taking your time to make SURE you're pulling straight and not crooked, try to loosen it.
Don't be surprised if the stud comes off as well. No big deal if it does, you'll just need to replace the stud and nut.

Do it right, if you screw up the stud hole you're going to need to replace your water pump [that's what the stud threads into]. That means doing your timing belt, and it doesn't sound like you're ready for that yet.

[Knix]

Thanks for the advise!! I will update

[alltracman78]

Now I remember why it wasn't making sense.
You don't have a top/bottom nut on the therm housing, they are on each side of it. The one closer to the exhaust manifold is stuck.
The silver round thing is your oil cooler. Your oil filter should be sitting on top of it.

You're going to have a PITA time getting vise grips in there, and needle nose ones probably aren't going to get the nut loose anyways.

A small 10MM should fit in there, you'll need a universal joint or wobble extension.

You can remove the oil cooler, but honestly it doesn't sound like whoever is working on this is all that mechanically inclined [I don't mean that in a deragatory way]. You could try taking it off, but you might just be digging the hole deeper....