- mischman wrote:
- Someone want to explain to be the basics of timing on a TCs engine? I was told it had a chain and not a belt so it couldn't break and i never needed to worry about replacing it? True?
I know timing is basically what controls when fuel being let it to fire and when exhaust is being let out.
Yes it is a timing chain in the tC not a belt. Unlike a belt it does not require replacement as maintenance.
The timing chain(or belt) in a short explanation syncs the cams and crank so that the valves open at the correct time in relation the the position of the pistons.
While a timing chain is not something that normally needs to be serviced (unlike a belt), I have seen a cases, not just in a 2az but in other chain motors (gm Eco tec 2.2 comes to mind) where the timing chain guides wear out and causes the chain to rattle, and if let go to long can cause the the chain to jump teeth on the sprocket throwing it out of time. On most chain motors(and some belt motors) including the 2az they are what is called an "interference motor" which basically means if the timing is out due to a jumped chain, broken chain, etc the valves and pistons will not move in sync with each other causing them to contact which will cause major engine damage, such as bent valves, cracked pistons, bent rods, etc.