Timing Belt Kit
A timing belt kit consists of the timing belt and the tensioner and idler bearings that keep the crankshaft and camshaft turning in sync — a critical service item whose failure causes severe engine damage.
Prepared by the Bicops Technical Content Team · Last updated:
Shop Timing Belt KitWhy is it critical?
The timing belt keeps the valves moving in the correct relationship with the pistons. If the belt snaps or jumps a tooth, a piston rises while valves are open; in most modern engines that means bent valves and a damaged cylinder head. The repair costs many times the price of the kit, which is why a timing change is not a service to postpone.
When should it be replaced?
Manufacturers usually give a dual criterion such as 60,000-120,000 km or 5 years, whichever comes first. Because the rubber ages and hardens even in a lightly used car, the time criterion is decisive when mileage is low. A whistle or ticking from the engine, cracks on the belt surface and worn teeth call for immediate inspection.
What the kit should include
A proper replacement renews the belt, the tensioner bearing and the idler bearings together; a seized bearing is no different from a snapped belt. In engines where the belt drives the water pump, the pump is replaced during the same labour, because a pump that leaks later means repeating the entire job. After replacement the timing marks and tensioner setting must be checked against the manufacturer’s values.
Frequently Asked Questions
Is the engine destroyed if the timing belt snaps?
In interference engines the valves strike the pistons and severe damage occurs. In non-interference engines the car stalls but usually no damage results; the large majority of today’s engines belong to the first group.
Do timing chains need replacing too?
In chain-driven engines the chain is designed to last the life of the engine, but the tensioner and guide plastics wear. If you hear a metallic rattle on cold start, the chain kit should be checked.
Should the water pump be replaced with the timing kit?
Yes if the pump is driven by the timing belt. Since the labour is entirely shared, replacing the pump on a separate date means paying the same cost twice.