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Nate Nagel

wrote:
On Tue, 08 Dec 2009 17:26:19 -0500, Jim Elbrecht
wrote:

Oren wrote:

On Tue, 08 Dec 2009 16:46:30 -0500, George
wrote:
-snip-
How would slipped timing cause the piston to hit anything? Never heard
of such a thing.

Just consider basic mechanical engine timing. If the engine is an
interference design (common on many higher performance and import
vehicles) the pistons can definitely collide with the valves if basic
mechanical timing is lost (eg, timing belt stretches and jumps a tooth).
Them dang ferrin cars. I didn't think about them. Thanks. Learned
something new.
If by 'ferrin' you mean GM or Ford- then OK. Both have engines that
can cause pistons and valves to collide if the timing belt slips.

Jim

My wife had the timing belt let go on her 1998 Toyota Rav4 while
powering up a steep hill. The engine simply stopped. No big bang, or
anything. The entire repair consisted of installation of a new belt
and idler assembly. No collateral damage.

Most higher performance engines are "interference" designs and do not
suffer failures so gracefully. A high compression ratio and the ability
to break a timing belt without crashing valves are mutually exclusive.

nate

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