This article will show you the steps necessary to replace a timing belt on the Camry 4 cylinder. This repair is the same for the 92, 93, 94, 95, and 96 year models.
Instructions
- 1
Make sure the car is in Park with the emergency brake engaged if you are doing this "on the ground" (without a lift). First you will want to disconnect the negative battery cable. This will prevent any sparks or shocks which can hurt both you and the car. Next drain the coolant from the radiator. There is a drain plug on the bottom of the radiator, simply unscrew it until you get a steady flow into the drain pan. Do not unscrew it too far, or it will fall out and you will have a river of coolant going everywhere. Once it stops draining tighten the drain plug.
2Next, disconnect the wiring harness from the alternator. Now, remove the alternator. This is basically a self explanatory step. Remove the passenger side tire to give you more room. Jack the right front of the car up, place a jack stand under the car. Loosen the bolts that hold the P/S (power steering) pump to the back of the motor. I use a 20" extension with a 12mm swivel socket to loosen the bottom bolt and a pry bar to pry the pump towards the motor. This will put slack in the belt so that you can remove it. You now need to remove the motor mount that is attached to the strut tower. You do not need to have anything to support the motor while removing this mount. The motor will move slightly, but not very much.
3With the motor mount removed you now have access to the top timing belt cover. Remove the 10mm bolts that hold the cover on. Note that these bolts also secure the wiring harness behind the cover, remember to put this harness back in place when you go back with everything. Next you need to remove the crankshaft pulley. This will require an impact socket, and a 1/2" drive impact wrench. Most of the time it takes a lot of power to remove the crankshaft pulley bolt due to the fact that the bolt has probably not been removed in some time, if at all, and the engine's rotation helps to keep it tight. I prefer to use PB Blaster or Deep Creep on the bolt and let it soak for a while (10 minutes or so). You can go ahead and get it soaking while you are removing other parts. Once you get the bolt out you will usually need to get a couple of pry bars or very large flat-head (standard) screwdrivers behind the crankshaft pulley and work it off of the crankshaft. Sometimes they will fall right off just using your hands to "wiggle" it off. Sometimes you're the windshield, sometimes you're the bug.
4With the crankshaft pulley off you need to remove the lower timing belt cover. There are several 10mm bolts holding it on. It will require a couple of different lengths of sockets to get them all out. Once the cover is removed your next step is to get the motor mount bracket out of the way. The bolts can be a little tricky to get to. I have found the best way (for me) is to use a long ratchet with a short 14mm socket, and to stand in front of the car and access the bolts from this angle. You may also try to remove them from the bottom. With the mount bracket removed you now have more access to the timing belt and related components. Reinstall the crankshaft pulley bolt and tighten it by hand. This will allow you to rotate the motor to align the timing marks. On the crankshaft gear there is a VERY small dimple that aligns with a mark on the motor. The mark on the motor (a small triangle) is at roughly 11 o'clock. After you line these timing marks up look at the camshaft gear and you will see that on one of the spokes there is a hole. You need to use a mirror to line this hole up with the dimple on the cover that is behind the camshaft gear. (It is at roughly 1 o'clock) If this hole is 180 degrees from where it should be you need to rotate the motor 1 more revolution at the crankshaft and it should now be lined up, or close. Once lined up I like to take a silver (metallic) Sharpie and make my own mark on the camshaft gear and on the backing plate that is behind it. You can make this mark where ever it is convenient for you. As long as you know where your marks line up, that is all that matters. This way I don't have to use the mirror as often.
5Once you have your timing marks aligned you need to locate the tensioner. The tensioner obviously keeps the appropriate amount of tension on the timing belt. You can find it by looking for a pulley that has a spring attached to it. You will need to loosen (not remove) the bolt that holds the tensioner on. Now that the bolt is loose you need to push the tensioner over (in the direction of the spring) to remove all of the tension from the belt. You can do this by hand, or use a screwdriver to push it over. Once you have it over as far as it will go, re-tighten the bolt. This will keep the tension off of the belt. You can now remove the timing belt. If you are only going to replace the belt, skip to step 10.
6Once you have the timing belt off, inspect it. Timing belt fatigue cannot be detected, however, you should look for signs of belt damage. Are there missing "teeth" or cuts in the belt? This could be a sign that a gear has sharp edges that are cutting into the belt. If so they would need to be replaced. I ALWAYS recommend that people replace all components related to the timing belt (camshaft/crankshaft seals, oil pump seal, water pump, and the tensioner and idler pulleys) while they are at this point. Yes it will cost you more now, but it will save you tremendously in the long run. You do not want to do a timing belt and a week later have the water pump, or one of the seals start leaking. Remember that a timing belt that is contaminated with oil will have a shorter life, not to mention that the oil leak can end up shortening the life of your motor by letting the oil level get too low. It is already expensive and time consuming enough, you don't want to have to replace a timing belt any more than you have to. If you do choose to replace all of the parts related to the timing belt you will need to remove the tensioner pulley, idler pulley (the pulley without the spring), the oil pump (located at about 11 o'clock from the crankshaft). If you are going to replace the camshaft and crankshaft seals you will need to remove the gears. We'll start with the camshaft gear. If you don't have a camshaft gear holder, it is a great tool to have. You can try your local auto parts stores to see if you can rent one. I have also used about an 8" extension and placed it through the "spokes" of the camshaft gear and rested it on the head of the motor. Since you will be turning the bolt counterclockwise you will need to place the extension on the left side of the gear because this is the way that it will rotate. Don't worry about the gear moving, you can put it back into place later using the marks you made earlier. Holding the extension tight, use a ratchet (the longer the handle the more leverage) and socket break loose the bolt and remove it.
7Once you have the bolt out slide the camshaft gear off of the camshaft and set it aside. I can't remember right off hand if you will need to remove the backing plate on this motor or not. If all of the seal is visible you will not. However, if some of it is covered by the backing plate you will. All you have to do is remove the 10mm bolts holding it on and set it aside as well. At this point you have access to the camshaft seal. It is best to remove the seal with a seal puller. Some parts stores may rent these as well. If you do not have one or are unable to get one, you can use a flat-head (standard) screwdriver and a hammer to get the seal out. If you must do it this way be VERY careful! If you nick or cut the camshaft it will then cut into the new seal, ruining it, you will have to use sandpaper to smooth it out again. I have found it is best to place the screwdriver between the seal and the camshaft cap (it looks like a half moon with two 10mm bolts holding it down) on the head. Once you have the screwdriver in place gently tap it with the hammer to try to push it in between the seal and the camshaft cap. Once it starts going in, continue until it stops going any further. Now you will need to GENTLY pry the screwdriver up, which will in turn pry the seal outwards. Be very careful doing this. Work your way around the seal and it should come out. Once the seal is out clean out the area. You can use brake parts cleaner for this (available at any parts store). Take your new seal and apply grease around the inner hole that will slide over the camshaft. If you buy a factory seal it should already come with the grease in it. Push the seal in evenly as far as you can with your fingers. You now need to "seat" it. If you have a small hammer you can gently tap the seal in place. Once the seal is in place reinstall the backing plate (if necessary) and the camshaft gear. Reinstall the bolt into the camshaft gear tightening it the same way you loosened it. If you used the extension method note that the extension will need to be on the right side since you will be turning the bolt clockwise to tighten it.
8Now on to the crankshaft seal. Please note the Woodruff key on the crankshaft. This looks like a metal half circle that sits in the crankshaft. DO NOT lose it! If you do you will have to find it or replace it. This is what keeps the crankshaft pulley/gear from rotating freely on the crankshaft. Removing the crankshaft gear can go 2 ways. Sometimes you can just wrap your hand around it and pull and the gear will come off. Other times you will need to pry it off. This can be difficult due to its location. This is a time where you will have to find what works for you with what you have. If you have 2 smaller, stronger screwdrivers you can try to insert them behind the gear on opposite sides and "rock" them back and forth. Pull one side then the other. Once the gear is off you will need to insert a screwdriver between the seal and the engine block. Again tap the screwdriver in with a hammer until it stops, and then pry the seal out. Work your way around the seal doing this and it should come out fairly easily. Clean out the area that the new seal will go in with brake parts cleaner. Lubricate the seal as you did with the camshaft seal and push it in evenly with your fingers as far as you can. Now what I like to do is take a short (3" or 6") extension and a hammer and carefully tap all the way around the seal using several passes to seat it. DO NOT try to fully seat the seal with one hit. Take your time and make slow, soft taps with the hammer. Once the seal is seated reinstall the crankshaft gear. You may have to tap it on with a hammer.
9Now remove the oil pump. Make a note that the bolts on the oil pump are different lengths! What I like to do is set the bolts down in relation to where they are on the oil pump. You could also draw a sketch of the oil pump and place the bolts on the holes that you drew on your sketch. Once you have the oil pump removed you will notice an O-ring. There is also a gear inside that looks like a circle with a hole shaped like a star. Make note of which side faces out. I always take this out and clean everything with brake parts cleaner. Sometimes it will take some effort to remove the O-ring. Use a screwdriver or scraper to remove it. I like to apply grease to the new O-ring so that it will stay in place during installation of the oil pump. Reinstall the "star" gear. Reinstall the oil pump with the bolts in their original locations.
10To remove the water pump, remove all of the bolts, again making note of their lengths and locations. With the water pump removed you will need to remove the gasket and clean the engine block where the new water pump will go. If the gasket is metal simply pull it off, if it didn't fall off already. However, if it is a "paper" gasket you will need to scrape off what is stuck to the engine block. Make sure you get every last little bit. If there is any left the new gasket will not seal properly and you will have a leak. Clean the area, and make sure that it is completely dry. Install the new gasket on the water pump, and reinstall the water pump with the bolts in their original locations. To replace the idler pulley, simply remove the bolt and install the new pulley. To replace the tensioner pulley remove the bolt and remove the pulley. Notice that there is a hole in one side of the backing plate that a dowel sits in. This gives the pulley the ability to pivot to place tension on the belt. Also note the location and direction of the spring. Install the new tensioner pulley on the dowel and thread the bolt. Do not fully tighten the bolt yet. Once you have the bolt almost flush, install the spring. With the spring installed you will need to again push the tensioner pulley towards the spring to remove all tension to aid the installation of the new belt. Once you have it pushed over as far as it will go, tighten the bolt. Install the timing belt starting with the crankshaft gear, then go over the idler pulley and the tensioner pulley. Finally, push the belt onto the camshaft gear. It is easiest to start at one side of the gear and work the belt onto the rest. Don't put too much of the belt on the gear to start with, or you will not have enough slack to get the belt over the rest of the gear. (Note: some people prefer to go in a different order than I do.) You can start with the crankshaft pulley, go over the idler pulley, then the camshaft gear, and finally the tensioner pulley. I prefer the first method simply because for me it is easier to get to the camshaft gear. Also be aware that it will most likely take you several attempts to get everything right. Don't worry, it will eventually go on right. If you pull on the belt too much one of the gears may move resulting in the engine being out of time. If this happens, remove the belt, reset the timing marks and start over.
11Once the belt is in place check your timing marks again on the camshaft pulley and crankshaft pulley. I like to check the mark that I made on the camshaft pulley, and also use the flexible mirror to check the marks on the gear and motor just to be sure. Now loosen the bolt on the tensioner pulley to place tension on the belt. Move the belt back and forth to see how much tension is on it. If it feels too loose, you will need to push/pry the tensioner pulley away from the spring and tighten the bolt. Check the tension on the belt again. It is almost impossible to describe what is proper tension. Too tight and it will reduce the life of the belt, too loose and it could slip, resulting in improper timing. You basically have to go by feel here. They do make a tension gauge to check this, but I have never seen one. Once everything checks out, reinstall everything in the reverse order. I would type it all out here, but it will be easier if you just print it out since you will need to have it with you while you're doing the work anyway. Refill the radiator with a 50/50 mix of antifreeze and water. (Although it may seem like a good idea to use only antifreeze, this actually does not offer the protection for your engine that a 50/50 mix will.) Refill the coolant resevior with antifreeze. Turn the heater to hot, and start the car. (This will insure that the coolant circulates through the heater core, and will help you to fill the radiator.) Let the car warm up with the radiator cap off as the coolant level will start dropping as more of the coolant gets circulated. Add more of the 50/50 mix as necessary. When it seems that the radiator is full, install the radiator cap. Wait for car to get to N.O.T. (Normal Operating Temperature) and for the fans to cycle (come on and then go off) then turn the car off. Wait until the car completely cools down, this may take a while. Recheck the coolant level in both the radiator and the coolant resevior. Top off as necessary. *DO NOT remove the radiator cap while the car is hot. The coolant is under pressure and will look like Old Faithful if you remove the radiator cap, causing severe burns.
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