1. Interference and Timing
Object: To distinguish between interference and non-interference engines, as well as emphasize the importance of timing belts.

2. What is a Timing Belt?
Timing/Gilmer/Cam belt is part of an internal combustion engine.
Material: rubber
Purpose: control timing of engine’s valves
Some engines use gears or chains instead.

3. What does a timing belt do?
Turns the camshaft at exactly 1/2 the speed of the crankshaft
Maintains a precise alignment. 
This means that the crankshaft will make two revolutions for every revolution of the camshaft. 
The camshaft causes valves to open and close in time with the pistons which move up and down in the cylinders. 
The valves must open and close in precise timing in order for the engine to work

4. Breaking and Replacing
Must be replaced every 96,000 km to 168,000 km
Must be replaced if there is any damage like cracks, cuts or excessive wear
When it breaks, camshaft stops turning leaving some of the valves in the open position. The crankshaft continues to rotate by inertia.
The engine will stall, leaving you stranded.

5. Interference vs Non Interference
Interference engine: pistons will strike the valves that are left open resulting in broken or bent valves, damaged pistons, and possibly, destroyed cylinder head.
The damage will be less extensive in a non-interference engine