I need really good instructions on how to remove the lower thermostat housing on a 95 960. I broke mine trying to remove the thermostat. (Too much tapping on those frozen bolts).
I'm really in a quandry now. Someone please help!!!

Man you are in trouble. The sears bolt remover. Get one. You have three bolts holding the housing two on top on the bottom. Same type of bolt.
Maybe you can repair the housing. As long as the gasket is sealing you can mend it with anything. Drill new hole somewhere for new bolt. Don't know just a suggestion. I don't know how is broken.

It broke on the lower part of the housing. The one that bolts to the cylinder head. It didn't come clean off, it just cracked. I can't drive the car, obviously, but it looks very difficult to reach those three bolts.
What other components am I going to have to remove in order to get to the three housing bolts?

You may have to remove the bracket that support the serpentine belt tensioner. That one is not to bad and may be enough. If you have the remove the big bracket tou can remove it with everything on it if I remember well, but not sure. Or maybe the steering pump alone. That one has three bolts you reach throuh the holes in the pulley.
Look at the prints I think they will help.

http://webpages.charter.net/volvito/

I JB Welded the crack in the top of the lower Thermostat housing, filled the cooling system back up and saw that it was still leaking coolant from somewhere. I think I must have cracked the block or the head.
In that case, I will be scrapping it.

I don't think you cracked the cylinder head. That would take some serious hammer blows. You probably damage the gasket to the lower housing, have another crack or things are not sealing well around the thermostat. Work 30 minutes a day. Take things apart as you need and note every bolt in plastic bag. write notes about the order you take things apart. You need to take the housing out and get a new part. Housing and thermostat coupling. JB welding is risky there. The cooling system build up pressure.

I was told I need to move the power steering pump. Do I need to release the tension on the serpentine belt before I do this? What do I do this with? I have a 3/8" socket wrench and that is too small for the square hole in the tensioner.
What do I use to turn the tensioner?

You have to build a tool. I made one with a piece of square tubing from lowe's. You have to file it just a bit and will fit perfect. Anything strong enough will work realy. Maybe a 1" socket adapator may also work, not sure. I build most of my special tools from scrap from my basement. There is a hole to put a pin once you release the tension, line it up and insert the pin. The steering pump has three bolts you reach through the holes in the pulley.
Main thing when you get a headache stop write some notes and come later or tomrrow. It will be easy. I mean humans put this thing together, you can do it.

I was thinking that you can just push the tension pulley back with your hand at the bottom where it meets the belt and someone can help you with the pin.
When you get to the bolts to the lower housing, if they are also stubborn I don't know if you have room there for a bolt remover, but if you don't you are going to drill them out. Get small bit and drill a hole right at the center about one inch deep. Then a big fat bit to eat off the bolt's head. Once the housing is removed continue drilling out the bolts with bigger bits. Don't get a bit that is to large. The bit may ran to the aluminum because is softer. Little by little until you are about the diameter of the bolt. Then re-tap the hole. You can buy one single tap in Napa or Carquest. Main thing don't get a headache over this. go one day at the time and that car will be running in a week or ten days.

You didn't hurt the head or block.With the PS pump out of the way,the bolts can be accessed with a good quality three or four inch long torx tip with 3/8 drive.Use snap-on or craftsman or similar good quality tool.

Obtain the new housing,gasket and screws from Volvo and re-assemble.I find that the torx screws are best loosened with a straight,steady pull with slowly increasing pressure.A sharp pull will often round off the tool or the points in the screw.

Its not a disaster,just a minor setback.

Bill

Do I have to relieve the tension on the serpentine belt tensioner to remove the PS pump? What do I use to move the tensioner back? I know you have to insert some kind of pin once you have it where you want it, but what fits in the hole of the tensioner?

I use a square nut,a short hex bolt,and a flat washer from the hardware store.I believe the square nut measures 3/4 inch across the flats.Screw them together,turn with a wrench,slip a nail,allen wrench or similar tool into the hole and slip the belt off.Sorry I don't have the exact measurements,but my garage is across town from my home.

Bill

Good news and bad news: I got the 3/4" square bolt from the hardware store and was able to release the serpentine belt tensioner. I took 3 (!) bolts out of the power steering pump and it still sat in there tight as a drum, so there must be at least two more I can't see.
I put the bolts back and will be taking it to a shop tomorrow, providing I don't lose all the coolant in the 60 seconds it takes to get there and do more serious damage, like warping the head, since I can't afford a tow truck.
Thanks anyway for all the advice.

There are three bolts. Probably the alternator bracket is holding everything too tight. Loosen the alternator and should come out. Anyway I f you can avoid any red light you may make it to the shop. I am not sure of the layout of the condenser on that car, but if you pull the two clips on top of the grill and pull the grill out, you may see three plug or maybe one to the left of the condenser. Disconnect that and with the ignition ON put a jumper and see if the fan comes ON. If it does that will give you extra cooling. If you have three plugs I am sure one will work on low speed and the second one at high speed.
If you cannot do any of that. Turn the heat ON inside the car to max and run the fan to max. That will cool the water going through the core some.