timing chain & gears

[JRSJ]

I went A/M with my timing chain/sprocket set. 23,000 km on it so far.

...what would the chain "rattling" sound be? I have a low rattling sound(diesel-like) at low rpm's that I thought was just the muffler touching the bellhousing. It goes away when I give it the slightest bit of gas. Is that possible the timing chain? Lots of power though...

Its so hard to diagnose noises on the internet without an isolated sample, and even then its better to be with the vehicle using a mechanics stethoscope or a long screwdriver. In my experience, chain/guide/tensioner slap usually manifests after you've let off the accelerator or at idle. Note: I've never heard it on a 3Y/4Y, only on my buddy's 22R.

(Of course the 22R is an OHC engine, using a single roller chain with a plastic backed chain guide that usually breaks. Luckily, our vans inherited a pretty stout timing package from Toyota, the simple joys of pushrod engines.)

More commonly, when the engine is cold, you'll hear lots of valvetrain chatter. Sticky hydraulic lifters are usually the culprit. Does the sound go away when the engine is at operation temp?

Regardless, doing a timing chain jobby isn't too bad, and in some ways its kind of fun.