Is the 4Y an interference engine?

[Ierfaan]

Please confirm or reject that the 4Y is an interference engine.

Does valves bend when the timing chain breaks or not?

Where do I get hold of a 4Y timing chain casing and front cover?

Thanks in advance.

[Bear]

The answer to your question was answered by Mud Dog in your previous post.

[Mud Dog]

Hi Ricky. Yes I answered that but in retrospect and after some thought I think I may have been mistaken.

If memory serves me correctly, the valve travel protrudes significantly past the head surface but the 4 Y pistons have a deep depression / combustion chamber which I think makes it non-interference.

Ierfaan, if the valves fouled and are even slightly bent, they would become sticky and it would be immediately noticeable.If not by eye, then by poor compression after you've sorted your cam chain issue and set up the valve timing.

[Ierfaan]

Thank you for the guys that responded.

Just to confirm. I did not experience any issues. After chain kit replacement, it started right up, hence no bent valves.

4Y is a non-interference engine and in my experience does/did not bend valves.

[Mud Dog]

[Bear]

That,s great stuff Ierfaan.

Sometimes even on interference engines valves may not necessarily bend. It depends on the speed of the engine etc.
As Mud Dog stated “the valve travel protrudes significantly past the head surface but the 4 Y pistons have a deep depression”
Is the depression sufficient in order not to bend valves?

There must be some experienced guys here to confirm that.