Non-interference engine explanation animation/Videos?

Question

Non-interference engine explanation animation/Videos ?

I did ask my Toyota dealer about published material on 1999 Camry 2.2 non-interference engine that did not cause piston hitting valves/ valve bent condition during timing belt slipping off spindle event.

They did not find any. I searched toyota.com , gates.com & alldata nothing showed up.

Are there any such material exist?

I found the generic piece http://www.samarins.com/glossary/dohc.html

This page, from Gates' website : http://www.gates.com/products/automotive/passenger-car-and-light-truck/timing-system/automotive-timing-belts

It explains only one part, Interference Engine. Did gates purposefully omit the Free Running explanation?

Toyota should be proud of explaining about their non-Interference Engine characteristics, but they are shying away in reality.

Thanks for your comments update 7/4/2015.

I do see "non-interference (or free running) motor does not have pistons and valves which share the same space - if the cam/valve timing is interrupted, no damage between cam and valve should occur." in various blogs/forums.

How does a mechanic learn/operate upon it? I did not find this info in repair manual/ALLDATA etc. Is it documented in repair steps?

Does all non-interference (or free running) motor have same characteristics/behavior ?

Thanks for sharing.

Answer 1

I don't know about material showing the difference, but the explanation is pretty easy: an interference motor has pistons and valves which share the same space within the engine at different times - if the cam/valve timing gets interrupted for any reason, damage between cam and valve may occur; the non-interference (or free running) motor does not have pistons and valves which share the same space - if the cam/valve timing is interrupted, no damage between cam and valve should occur. (NOTE: There are engines out there which are touted as non-interference, but this means no piston to valve interference. These same engines may have valve to valve interference. This refers to some of the newer engines, which have DOHC and four valves per cylinder.)