Thanks again, Phunkdoktaspot, Steven and
Dats-Hot, for the help.

Sorry to have to bother you people for help again,
but there is no similar Toyota KE70 website with
a good and very active forum like yours around,
apart from a couple in Yahoo which aren't very
good.

I'll go get the whole works - chain, tensioner,
sprockets and L-plate changed soon as I can. You
young guys are really good to do it yourselves - no
car owner in Malaysia knows how to do it
themselves. Has to be done by the mechanics, and
even they will take virtually the whole day to finish
it, replacing a timing chain is a really major job,
unlike a timing belt.

The cylinder head gasket and valve seals and guides
were changed a few months ago with a gasket set, and
the valves decarbonized. The tappets are making some
noise now, but the rattling is definitely the timing chain
- gets louder when the aircon compressor cuts in. It's
been rattling for years actually. It's even noiser if I use
a lighter oil such as SAE 30 or the 15W-40 which I am
using now. I'll have to switch back to 20W-50.

By the way, I think the earlier problem in my first post
about the engine idling roughly and stalling in hot
weather, might well have been vapor lock. I've wrapped
the fuel lines running to and from the fuel pump in
aluminium. If that still doesn't work, I might have to
change over to an electric pump.