A timing belt is a mechanical tool that transfers motio […]
A timing belt is a mechanical tool that transfers motion to the camshaft from the crankshaft of a reciprocating internal-combustion engine and sometimes it also transfers motion to some of the engine driven accessories. By connecting crankshaft to the camshaft, it will keep the cams turning at the same rate as the crank at a Timing Belt Company. It will make sure the right valves are opened at the right time every time a stroke is made by a piston.
So for simplicity let's just say that piston connects to crankshaft, and crankshaft connects to camshaft, and camshaft connects to valve.
Timing belt is cheaper to manufacture than timing chains or gears, it's also quieter when operated. A timing belt doesn't need lubrication. But one disadvantage of timing belt is you need to replace it every certain interval.
When the timing belt slips just by one tooth, the engine stops operating. In several cars it will produce costly damage especially to the pistons and valves. When the timing belt drops or fails, you will not be able to start the engine. If this happens you should not try starting the engine again.
How to Check Belts
1. Turn off your engine.
2. Open the hood of your car.
3. Find the belts, they are located on the very front of your engine. If you have a rear wheel drive car, the front of your engine is usually adjacent to the front bumper and the radiator. Otherwise if it's a front wheel drive car then the front of of the engine is often adjacent to the fender.
4. Note that there are 2 or more belts, it depends on the car models.
5. Press lightly with thumb at the belt's longest part between pulleys. Do this on each belt.
6. Find out the normal tension for your belts. It's in the car's manual. Normally belts cannot have more than one inch of "give" in both direction.
7. Evaluate those belts as you press them. If the belt is cracked or can be easily pushed more than one inch, then it's highly advised to replace with a new one.
How to Replace Timing Belts
The first thing to remember is to wait for your engine to cool off. You may want to wait at least a day after running your car.
Your next step is to disconnect the negative battery cable. After doing this make sure any obstructions to the timing belt cover are out of the way. This may take a bit of time and may include air intake assembly, the water pump pulley and other accessories. Each car is different and will have different things that may interfere.
You may want to check a repair manual for your car's particular model to see if your car has a distributor cap. If it doesn't have one, then it should tell you what to do from there. This may be as simple as making sure the cam position sensor is set to TDC. Otherwise, just remove the distributor cap.
Next, using a wrench on the bolt of the crankshaft, rotate the engine until the timing mark on the pulley is lined up with the "0" mark on the timing scale. Then remove the timing belt cover. Check the timing belt tensioner bearings and replace them if they are loose. Move the tensioner away from the belt. You can then slide the timing belt off to remove it.
After this, put the new belt in place and adjust the tension as necessary. Be sure it fits properly over the teeth of the timing sprockets, but don't make it too snug.
The next steps are fairly simple: apply a new gasket onto the timing belt cover, reinstall all of the items you previously disconnected, reconnect the battery and start the engine to see how it runs. If it knocks, you may have missed something. If it doesn't, then you have successfully changed the belt.
By the way, this may be a good time to check your battery since disconnecting it is one of the first things you'll have to do.