How to Replace a Timing Belt in Your Car
Most car owners know there are certain things they need to do on a regular basis in order to keep their cars running properly. Some of these things include performing tune-ups every twelve to fifteen thousand miles, changing the oil and filter every three to five thousand miles, rotating the tires every 5,000 miles, and changing the brakes as needed. However, most car owners don’t know there are other regular maintenance items that should be performed in order to keep their cars running properly and to prevent serious internal damage to their engines. One of the most important of these often-forgotten maintenance items is changing the timing belt at regular intervals. If the timing belt fails, the best you can hope for is for your car’s engine to quit working, while very serious internal damage, including bent and broken parts, can also ensue. The exact method of changing a timing belt varies from engine to engine, so I’ll outline the basic steps.
Tools You’ll Need
- Coolant drain pan
- New coolant
- New timing belt
- Ratchet with socket set and extensions
- Gear puller
- Flathead screwdriver
- Pliers
1. Drain Coolant and Remove Radiator
Place the drain pan under the coolant drain valve on your radiator, remove the radiator cap, and open the valve. While the coolant is draining, loosen the clamps on the upper and lower radiator hoses on the engine side. Next, use the ratchet and a socket to remove the nuts or bolts securing the radiator to the body. On some cars, these may be screws and not nuts or bolts and will require the use of a screwdriver, instead. Once the coolant has completely drained from the radiator, close the drain valve and move the pan under the lower radiator hose, grasp the lower radiator hose on the engine side and twist it back and forth while pulling to remove it. Allow the rest of the coolant to drain out.
2. Remove the Serpentine Belt/Accessory Drive Belts
There are as many ways to accomplish this as there are engine sizes and makers. In general, you will need to loosen and remove the accessory drive belt(s) or serpentine belt. On most newer cars, this can be accomplished by using the ratchet to rotate the serpentine belt tensioner pulley away from the belt and sliding the belt off the drive pulleys. Be sure to mark the direction of rotation of this belt prior to removal. Using the ratchet and a large socket, loosen the bolt securing the crankshaft pulley to the crankshaft. Leaving the bolt in the crank approximately three turns, attach the gear puller and loosen the crank pulley. Remove the puller, center bolt, and crank pulley.
3. Gain Access to the Timing Belt
This is where it can get tricky. On rear-wheel-drive vehicles, you will have to remove, or at least loosen, all of the accessories such as AC compressor, water prump, power steering pump, and alternator. On front-wheel-drive vehicles, you will have to support the front (passenger) side of the engine with a block of wood and a jack from underneath. The next step, on front-drive vehicles is to remove the passenger side engine mount.
Now you should have clear access to the timing belt cover on the front of the engine. On most 4-cylinder engines, this will be in two pieces and have between four and six bolts securing it to the block and head. On larger engines, this cover will normally be metal and have between six and ten bolts securing it. On these engines, there is also a gasket that will need to be removed and cleaned after cover removal.
4. Line up the Timing Marks
Replace the bolt in the crankshaft snout and use it to rotate the engine until the timing marks on the crank and camshaft gears line up the way they’re supposed to. You will need to verify the proper markings and line ups for your engine. Never turn your engine counter-clockwise during this procedure.
5. Out With the Old and In With the New
Once you have clear access to the timing belt, it can be removed simply by sliding it off the cam and crank pulleys. UNLESS you have one of the engines that has a timing belt tensioner. If this is the case, you will need a quarter inch Allen wrench to loosen the tensioner pivot. Once the tensioner is loose, the belt will come off easily.
Making sure that the cam pulley doesn’t move, slide the new belt over the cam and crank pulleys. If your engine has a tensioner, use the Allen key to rotate it to properly tension the belt and then tighten the pivot bolt.
6. Verify Timing Mark Alignment
Rotate the engine through two complete revolutions using the ratchet and socket and then verify that the timing marks are still properly aligned. If so, you can reverse the above steps to reassemble the engine.
7. Refill the Cooling System
Once everything on the front of the engine is back together, and the radiator is back in place and properly secured, you need to refill the cooling system with CLEAN NEW coolant. NEVER reuse old coolant, even it was very recently changed, as draining it from the engine introduces contaminants that can damage the engine.
Additional Tips
- Always wear safety glasses while draining or filling the cooling system. Splashed coolant hurts.
- On front drive vehicles, raise the right/passenger side and remove the tire to gain easier access to the belt through the fenderwell.
- An indispensable part of your vehicle maintenance kit should be a motor manual. This will have diagrams and photos depicting all vehicle maintenance procedures.
