Engine – Timing Chain
This is the chain that drives the camshaft, valve train and ignition system. It's a very important part in your engine dependability and performance. A little history on the Toyota 4 cylinder engine.
In 1975-82 the 20R through 22R engine used a double chain drive system. This was very dependable. In 1983-84 early 22R Toyota used a single chain with plastic guides. This chain is prone to stretching beyond the tensioner's limits, resulting in a slack chain. This engine family can be upgraded to the 1975-85 double chain kit.
In 1985-95 22R/RE, Toyota introduced a new designed engine family, changing the distance between the cam to crank center-line ie: shorter head and shorter block. This required a shorter single chain with plastic guide rails. "When introduced, LC Engineering experienced problems with this in their high performance R&D department. The chain will stretch beyond the tensioner's limits allowing the chain to slip against the plastic guides resulting in breaking the guides (that's the noise heard on cold start up). Prolonged engine operation will result in the chain wearing through the timing cover allowing coolant to leak into the engine crankcase.
This failure is often diagnosed as a cracked head or a blown head gasket. LC Engineering has three ways to prevent, or improve this problem.
- Toyota recommends changing the Chain Kit every 70-80k miles on a stock engine light duty application. This will work fine by using .
- Change the Chain Kit every 70-80k and upgrade to a Single Chain Late Steel Guide Kit. Warning: This will not prevent the chain from stretching. Prolonged engine usage will result in the chain breaking and that is much worse than a water leak. Suggested for use in light duty operation only.
- The LC Engineering Exclusive! Timing Chain Conversion Kit was designed in 1995 when we experienced these issues. This kit provides the customer with all the necessary components required to install a double chain with steel guides on your 1985-95 22R/RE engine. This Timing Chain Conversion Kit will outlast the vehicle and handle all the high performance demands that you require. Problem solved!
|