Under the Hood: ‘Perfect Timing’ — Timing Belt Service for Toyota’s VVT-1 Engine
The focus of this article will be the timing belt replacement on a 2001 GS 300 with the in-line six-cylinder 2JZ-GE engine with VVT-i (Toyota’s variable valve timing).
Under the Hood: Gearing Up for Timing Chain and Belt Work
Timing belts and chains carry a heavy load. They have to turn the cam with enough force to overcome the resistance of all the valve springs. However, the main cause of belt wear is heat. As a belt wraps around and turns the sprockets, friction creates heat (this is in addition to the heat from the engine itself). Over time, this causes the rubber to lose flexibility, harden and crack.
Web Exclusive: Gearing Up for Timing Belt and Chain Work
The best time for a timing belt or chain to be replaced is before it fails. Technical Editor Larry Carley discusses items to consider when timing belt or chain work arrives in your shop or school in this Web Exclusive article.
Getting Your Timing Down
Adapted from Larry Carley’s article in Underhood Service
Standard Motor Products Continues Growth of VVT Program
Recently released Standard variable valve timing (VVT) sprockets are now available for another 8.8 million vehicles.
VIDEO: What Can Cause An Oil Filter To Collapse?
Andrew Markel covers the possible root causes for a filter media to collapse due to extreme oil pressure. Ignoring the signs and hoping the new filter will correct the problem might lead to failure of engine bearings and variable valve timing components.
VIDEO: Oil Filter And Noise At Start Up
If you have a vehicle that comes to your shop with valvetrain noise at start up, the solution might be simpler than you think. Many engines have variable valve timing, these systems need to have engine oil to operate. If the oil drains from the top end of the engine, the actuators and lifters will make noise when the engine is started. The cause could be a damaged oil drain back valve in the oil filter.
VIDEO: How VVT Issues Can Ruin The Perfect Cam/Crank Alignment
Andrew Markel discusses timing components, and how issues with the variable valve timing actuator can cause codes from misalignment.
VIDEO: VVT: How Oil Is Like Electricity
Andrew Markel discusses the variable valve timing system, and how the behavior of oil in the system is a lot like voltage passing through a component or module.
VIDEO: VVT Actuator Rattles On Cold Start
Andrew Markel helps diagnose a customer complaint of a rattle or clunk from the engine when the vehicle is started in the morning, and how oil pressure could affect the variable valve timing system.
