quick question

[silvia_ca18det]

hey guys new to the forum and i love how much ca18 stuff is on here i am a personal ca18 builder and lover but anyways i have a easy question that i have gotten a few different answers from a few people on a ca18det if the timing belt snaps will the valves hit or is there enough clearence?

reason i wanna clerify this is cuz i have a buddy that had a "shop" look at his car and the "shop" said his timingbelt was ****ed and his valves are bent! i had a hard time beliving this as becasue the timing belt was replaced 10,000 km before, anyways sorry for the easy question i should know this but meh!

thanks

[themadscientist]

BANG I have seen CAs and RBs bust tining belts and not bend valves but only because it was at a point in rotation where all valves were closed just enough to clear the pistons. The chance of that happening is remote, think Russian roulette with five loaded chambers. Nismo, Trust (Greddy) and Powers enterprises all make HD timing belts, well worth the extra $50 IMO

[roe_wedge]

what are HD timing belts?

[F3600]

heavy duty timing belt i think

[float_6969]

Technically, this is an interference motor, and it completely possible to have the pistons smack the valves if the belt breaks. I might go back to the timing belt manufacturer and talk to them about it if the belt really broke after 10K Km.

[silvia_ca18det]

i was 90% sure it was an interfearence motor, but the other random people saying it was a non interference made me have to ask this, but yeah thanks for the quick help, i am going to actually look at my buddys car myself, i told him not to take it to a damn shop that knows nothing but domestics!

anyways thanks

[float_6969]

If it's any consolation, I had a KA-DE that jumped a timing chain. It's an interference motor and I didn't bend any valves on it.

[tyrannix]

i remember reading somewhere that theres 3mm of clerance between an open valve and the piston at TDC it was one of the 'CA is a great piece of engineering' articlesthat might be why those crescent shaped grooves are in tops the pistons

[silvia_ca18det]

i remember reading somewhere that theres 3mm of clerance between an open valve and the piston at TDC it was one of the 'CA is a great piece of engineering' articlesthat might be why those crescent shaped grooves are in tops the pistons

interesting......do you have a copy of the article?

[float_6969]

If this was true, then why would the FSM state, all over the place, to not turn the crank independantly of the cams of "serious internal damage can occur"?

[Nowhere]

If this was true, then why would the FSM state, all over the place, to not turn the crank independantly of the cams of "serious internal damage can occur"?

Carbon buildup ontop of the pistons, slightly filling the valve cutouts???Guess?