Mr. Winkey did this job and broke it down very well. I am adding this addendum because there were some things/questions his page does not tell.
I thank Mr. Winkey as I could not have done this job comfortably without his knowledge and web page. I borrowed some of his pictures to help everyone. Thank you Mr. Winkey.
I believe it's worth the ten extra dollars to buy the OEM timing belt kit which includes the roller, tensioner, and belt. I purchased mine through FCPgroton.com from Mike the manager. The cheaper is $129 and the OEM original Volvo kit is $139. Also replace the SERPENTINE belt, you have take it off anyways and it's easy to change while everything is torn apart. Some people replace the water pump since it's right there where the timing belt is. I did not. The reason is I'm not made of money and it is an additional $110 or so. I called the dealer and they said usually no one changes it unless it's leaking. There are never any guarantees with water pumps. It's up to you. Also there are kits with CAM seals and CRANK seals etc... I did NOT buy this. It is already a big deal doing this job without pulling gears and such without them leaking. If they are leaking (which most are not under 150K miles) then of coarse change them.
FIRST BEFORE YOU DO ANYTHING ON ENGINE. Jack up the passenger side and remove wheel (always use jack stands for safety) Otherwise you will run into a problem/situation half way through the procedure. Otherwise you will try to jack up the car and keep the engine balanced using a second jack. Don't skip this step.
SECOND BEFORE YOU START. You may want to break the nut free (loose) before you start to guarantee you can take it off later. You are going to have to break the crankshaft nut loose as described by Mr. Winkey. I am stating this because you need a "good" impact wrench. Not a cheap one. People tend to think that it's the air pressure and volume alone that takes off nuts with an impact. It is the impact gun itself that does 90% of the work. I use a 650 torque lbs. wrench from Home Depot. It cost about $140. There is an old trick also if you don't want to spend the money for a new wrench. I don't advise this but I've seen it done this way before. You take your 30mm socket and put it on a long breaker bar and let the handle of the breaker bar hit the cement. Then crank your starter over for just a second. This should break it free so you can undo it more easily. Most cheap impact guns are about 90 torque lbs give or take. So they don't work well.
THIRD. You can take off the lower plastic cover carefully if you pull up fairly hard and use a think screw driver to gently pry the plastic past the part where it touches the mount. If this does not make sense now, it will when you finally pull off the main mount attached to the frame of the car.
Mr. Winkey says: Start by removing the 2 T30 torx screws for the top cover and remove it. Then remove the 13mm nut holding the power steering line bracket and lightly loosen the 16mm flare nut on the pump pressure line. Now rotate that line upward and on top of the plug cover and snug nut back up to hold it's position.
MY TWO CENTS:
I took off the whole spark plug cover for simplicity reasons. That is all the plastic pieces that cover the spark plug wires plus the top timing cover. Also, be very gently when moving the power steering line up and over the cams. There is a plastic holder holding the hose. I turned my 16mm flare nut only 1.5 turns counter clockwise then moved it up. When done tighten the 16mm nut a little. You will be moving this again most likely during this process (up and down again), so not too tight.
Mr. Winkey talks about using a piece of wood under the oil pan. I brace my basically over the oil filter housing (it did not touch it) and the two corners of the oil pan. I used a 2x4. After removing the six 15mm bolts (2 nuts) attached to the car frame and mount you should be able to pull it off. If not try jacking up the 2x4 holding the engine just a little, it should come off then.
Mr. Winkey says: I'm removing the center mounting bracket on the motor for ease of pictures. This does not have to be removed when doing the job but I recommend it. You will need to remove 4-13mm bolts and the one mounting stud(red dot next to it) in order to get the upper bolt removed. This bracket is dowel pinned so you may have to wiggle it a bit once the bolts are removed.
MY TWO CENTS:
This can be one of the most important things that could cause you lots of stress and curse words. So I will help. You MUST remove this bracket. Though it is optional for an experienced person, removing this makes your life 80% easier. Basically remove the bolts. But the one bolt that you are cursing at because you can't get to it, is covered by one of the two "studs" that held the engine bracket on. Be calm. You are going to double nut the stud and back it out. It is basically screwed in. You will have to use a stubby monkey wrench or buy/find a nut without the flange on it so you can get a wrench on it. See picture.
Mr. Winkey says: Now use a long 14mm wrench and release the tensioner, remove the belt. With the belt out of the way you can remove the lower half of the timing cover by simply pulling out and upward (it slides into grooves on the rear cover)
MY TWO CENTS: The SERPENTINE belt is NOT the Timing belt. DO NOT accidentally try to remove the timing belt. I've seen this done before. There is a plastic cover that pops off the serpentine tensioner. Just use a small flat head screwdriver. I use a 14mm wrench and stick it through the closed end of a big monkey wrench so I can get good leverage on the nut. DONT get your fingers stuck between belt and pulley. This hurts a lot. Yes I've done it. DO NOT try to use the "star" type hole in the tensioner unless you have the correct tool. No normal person uses this whole only Volvo dealers. Pull the tensioner clockwise to so you can get the belt off.
Mr. Winkey says: Now reinstall the spark plug cover with the timing mark cutouts and with a 30mm socket rotate the crank and bring the motor up on TDC. The cam marks are very difficult to see (yes they are there) they are tiny hash marks so I paint marked them for this documentation. Align the cam gears straight up with the 2 cutouts on the underside of the forward spark plug cover. With it all in time go back down and remove the 4-10mm bolts and the 30mm crank pulley nut. (An impact gun is recommended for this).
MY TWO CENTS:
You don't have to mark your own timing marks on your car. They should be easy to see. When you line them up with they cutouts mentioned above, they may move when you remove the main crankshaft nut so always triple check. It is criticle but not ultra criticle you match the notches perfect because when you bend down to look at them your eyes will play tricks with you and probably tell you they are perfect when they are not. I usually turn mine ever so very slightly to the left because if you use a strait edge they line up but if you use your eyes they don't. When he refers to TDC (top dead center) he's referring to piston at the top of the stroke. Most people make sure the cam notches are lined up with the cutouts with timing belt on car. If your belt has broken you will have to take out the spark plug and do it manually. Also, the four 10mm nuts are on the crank pulley that he is referring to.
Mr. Winkey says: With the crank pulley removed I paint marked the crank timing mark that should be aligned with the pointer on the oil pump housing. If your timing marks are not aligned you may re-install the 30mm nut and rotate the assembly into time again.
MY TWO CENTS:
The oil pump housing mark is extremely difficult to see. You need a good light/flashlight. They should be lined up fine if your upper cam marks are lined up correctly. It's basically right in front of where Mr. Winkey marked it with paint in the shadow.
Next: Many mechanics don't use a cam holding tool (RED GIZMO). I do. Mine cost less then $25 online. BTW, my RED GIZMO has fallin' off the cams and they will shift to another position. Don't freak out. Just take your time, on the left gear it uses an allen wrench it will be very hard to turn but just turn the notch back to match the notch in your timing cover. On the right, I put a long thin screw driver between two of the three small nuts on the face of the pulley and turn it.
They will both stay where you leave them unless you touch them then they will "spring" back to frustrate you. Just put your RED GIZMO back on. These need to be very close to the notch like when you started. But not perfect. If I remember the most important thing is 18 teeth between the two on the belt once they are lined up.
Before taking off the timing belt look at your tensioner. That's about where it should be when you put the new belt on. Mr Winkey says it best in his article.
Here is the deal folks. This is a manual tensioner that adjusts itself depending on heat. It has inner springs inside. So, this step is important. YOU MUST ROTATE THE CRANK by hand with a long socket wrench or breaker bar and socket TWO times which equals one full rotation of the upper cams.
I can almost guarantee you, you will have to adjust the tensioner again. I start with it off where I think it is supposed to end up and so when it moves after turning the crank it ends up in the correct position. This takes a little practice.
Also, if you "bend" the thin metal on the tensioner "the little metal guide fingers" you must try to bend it back. I use long screw drivers. Needle nose do not seem to work. You can pull off the belt and start over but this is a b*tch. It does not need to be perfect just close.
There may be more I think of but for now this is it. It's free so dont' yell at me with complaints please. It's just an opinion. If it helps you say thanks. It's always nice to hear it.
Follow the rest of Mr. Winkey's instructions and put all back together again.